Hyuk Hur - Academia.edu (original) (raw)

Papers by Hyuk Hur

Research paper thumbnail of Laparoscopic-Assisted Versus Open Complete Mesocolic Excision and Central Vascular Ligation for Right-Sided Colon Cancer

Annals of Surgical Oncology, Mar 7, 2014

A concept of complete mesocolic excision (CME) and central vascular ligation for colonic cancer h... more A concept of complete mesocolic excision (CME) and central vascular ligation for colonic cancer has been recently introduced. The aim of this study was to evaluate and compare perioperative and oncologic outcomes after laparoscopic-assisted CME (LCME) and open CME (OCME) for right-sided colon cancers. The study group included 128 patients who underwent an LCME and 137 patients who underwent an OCME for right-sided colon cancer between June 2006 and December 2008. The propensity scoring matching for sex, body mass index, tumor location, and pathologic T and TNM stage produced 85 matched pairs. The median time to soft diet (LCME 6 days vs. OCME 7 days, p < 0.001) and the possible length of stay (7 vs. 13 days, p < 0.001) were significantly shorter in the laparoscopic group. The median operation time (179 vs. 194 minutes, p = 0.862) and number of harvested lymph nodes (27 vs. 28, p = 0.337) were comparable between groups. The morbidity within 30 days after surgery was comparable between the groups (12.9 vs. 24.7 %, p = 0.050). The 5-year overall survival rates of the OCME and LCME groups were 77.8 and 90.3 % (p = 0.028), and the 5-year disease-free survival rates were 71.8 and 83.3 % (p = 0.578), respectively. Herein, we demonstrated the feasibility and safety of LCME for right-sided colon cancer, and in terms of better short-term outcomes, LCME was more advantageous than OCME. Although LCME for right-sided colon cancer was associated with better 5-year overall survival, compared with an open approach, the long-term oncologic outcomes between the groups were…

Research paper thumbnail of Comprehensive Immuno-Molecular Profiles for Liposarcoma: Roles of Programmed Death Ligand 1, Microsatellite Instability, and PIK3CA

Oncology

Background: Developing personalized strategies for cancer has shown good efficacies. Methods: We ... more Background: Developing personalized strategies for cancer has shown good efficacies. Methods: We assessed the molecular targets programmed death ligand 1 (PD-L1), microsatellite instability (MSI), and PIK3CA. Seventy-four patients with liposarcomas who underwent curative resection were assessed for PD-L1 expression in the tumor and tumor-infiltrating lymphocytes (TILs), mismatch repair proteins (MLH1, PMS2, MSH2, and MSH6) by immunohistochemistry, MSI using polymerase chain reaction, and PIK3CA mutation/amplification using pyrosequencing and fluorescence in situ hybridization. Results: Seventeen (23%) cases were TIL+ (≥1 + expression) and associated with longer 5-year overall survival than those with TIL– tumors (84.4 vs. 60.8%, p = 0.007). Six (35.3%) PD-L1+ tumors were detected only in TIL+ cases, with none detected in tumor cells. Two well-differentiated liposarcomas showed MSI, one low and one high with concurrent loss of MLH1, MSH6, and PMS2. PIK3CA mutation was detected in 7 (...

Research paper thumbnail of Late anastomotic leakage after anal sphincter saving surgery for rectal cancer: is it different from early anastomotic leakage?

International Journal of Colorectal Disease

Research paper thumbnail of Transanal Total Mesorectal Excision for Rectal Cancer: Perioperative and Oncological Outcomes

Research paper thumbnail of Cost analysis of single-incision versus conventional laparoscopic surgery for colon cancer: A propensity score-matching analysis

Research paper thumbnail of Impact of tumor sidedness on survival and recurrence patterns in colon cancer patients

Annals of Surgical Treatment and Research

Previous studies have reported conflicting results regarding the prognostic value of tumor sidedn... more Previous studies have reported conflicting results regarding the prognostic value of tumor sidedness in colon cancer. We investigated the oncologic impact of tumor location and examined whether recurrence patterns were related to tumor sidedness in colon cancer patients. Methods: We identified stage I-III colon adenocarcinoma patients from a prospective colorectal cancer registry at Severance Hospital, Seoul, Korea, who underwent complete mesocolic excision between 2005 and 2012. Adjusted hazard ratios (HRs) and 95% confidence intervals (CI) for predictors of cancer-specific survival (CSS), recurrence-free survival (RFS), and cumulative recurrence at specific anatomic sites were examined using Cox proportional hazard regression analysis. Results: Overall, 1,912 patients, 1,077 (56.3%) with left-sided colon cancer (LCC), and 835 (43.7%) with right-sided colon cancer (RCC), at a median follow-up of 59 months, were eligible and included in the study. In univariate analysis, similar 5-year CSS and RFS were observed for LCC and RCC in the total patient population, and when stratified by stage for stage I and II patients. For stage III patients, an adjusted Cox regression analysis indicated that RCC patients had a higher risk of cancer-specific mortality (HR, 1.75; 95% CI, 1.07-2.86; P = 0.024) and recurrence (HR, 1.78; 95% CI, 1.22-2.60; P = 0.003). Furthermore, RCC was an independent predictor of peritoneal recurrence (HR, 1.86; 95% CI, 1.05-3.29; P = 0.031) in stage III patients. Conclusion: RCC correlated with worse CSS and RFS than LCC. In stage III patients, RCC correlated with increased risk of peritoneal recurrence. The reasons for these differences remain to be investigated.

Research paper thumbnail of Characteristics and Survival of Korean Patients With Colorectal Cancer Based on Data From the Korea Central Cancer Registry Data

Annals of coloproctology, 2018

The incidence of colorectal cancer (CRC) in Korea has increased remarkably during the past few de... more The incidence of colorectal cancer (CRC) in Korea has increased remarkably during the past few decades. The present study investigated the characteristics and survival of patients with CRC in Korea as a function of time, tumor distribution, stage, sex, and age. We retrieved clinical data on 326,712 CRC patients diagnosed between 1996 and 2015 from the Korea Central Cancer Registry. The incidence and the 5-year relative survival rates were compared across time period, tumor distribution, stage, sex, and age group. The percentage of patients with colon cancer increased from 49.5% in 1996-2000 to 66.4% in 2011-2015 while the percentage of patients with rectal cancer decreased from 50.5% to 33.6%. The 5-year relative survival rates for all CRCs improved from 58.7% in 1996-2000 to 75.0% in 2011-2015. For 1996-2000, survival rates were highest for patients with left-sided colon cancers, followed by those with right-sided, transverse, rectal, rectosigmoid cancers. For 2011-2015, the surviv...

Research paper thumbnail of Differences in the Efficacies of Pazopanib and Gemcitabine/Docetaxel as Second-Line Treatments for Metastatic Soft Tissue Sarcoma

Oncology, Jan 18, 2018

We retrospectively investigated the treatment outcomes of second-line treatment with pazopanib or... more We retrospectively investigated the treatment outcomes of second-line treatment with pazopanib or gemcitabine/docetaxel in patients with advanced soft tissue sarcoma (STS). Ninety-one patients who were treated with pazopanib or gemcitabine/docetaxel for advanced STS between 1995 and 2015 were analyzed. Forty-six and 45 patients received pazopanib and gemcitabine/docetaxel, respectively. The median progression-free survival for the group treated with pazopanib was 4.5 months compared with 3.0 months for the gemcitabine/docetaxel group (p = 0.593). The median overall survival for the group treated with pazopanib was 12.6 months compared with 14.2 months for the gemcitabine/docetaxel group (p = 0.362). The overall response rates (ORRs) were 6.5 and 26.7% in the pazopanib and gemcitabine/docetaxel groups, respectively. The following parameters had ORRs favoring gemcitabine/docetaxel: age ≥50 years (31.6 vs. 2.9%, p = 0.006), histologic grade 1-2 (40.9 vs. 0%, p = 0.001), and poor first-...

Research paper thumbnail of Temporal changes in immune cell composition and cytokines in response to chemoradiation in rectal cancer

Scientific reports, Jan 15, 2018

We measured systemic changes in the immune response in 92 patients receiving preoperative chemora... more We measured systemic changes in the immune response in 92 patients receiving preoperative chemoradiation therapy (CRT) and subsequent surgery for rectal cancer. The peripheral blood was sampled five times from the onset of CRT until surgery. Lymphocytes decreased continuously during CRT but increased after CRT. The increased lymphocyte population was predominantly CD8+ T lymphocytes, which accounted for a significantly larger proportion in patients without residual lymph node metastasis than in those with residual lymph node metastasis. Neutrophils and monocytes decreased during the initial two weeks of CRT but were maintained or increased afterwards. Neutrophil and monocyte counts were significantly lower in patients with a pCR (pathologic complete response) than in those without a pCR two weeks after CRT began but not at the initiation of CRT. All cytokines showed dramatic changes one month after the termination of CRT. Cytokines related to the antitumour immune response increased...

Research paper thumbnail of Long-term outcomes after stenting as a bridge to surgery in patients with obstructing left-sided colorectal cancer

International journal of colorectal disease, Jan 12, 2018

Self-expandable metallic stents (SEMS) may be used in acute, obstructing, left-sided colorectal c... more Self-expandable metallic stents (SEMS) may be used in acute, obstructing, left-sided colorectal cancer (CRC) to avoid high-risk emergency surgery. However, the data regarding the long-term effects of SEMS as a bridge to surgery are limited and contradictory. Our aim is to analyze the long-term oncological outcomes of SEMS compared with surgery. Between January 2006 and November 2013, a total of 855 patients with stage III CRC were regularly followed at the CRC clinic of Severance Hospital, Seoul, Korea. We retrospectively evaluated their 5-year disease-free survival (DFS), 5-year overall survival (OS), and 5-year cancer-specific survival (CSS). There were 94 patients in the SEMS group, 17 in the emergent-surgery group, and 744 in the elective-surgery group. In the short term, the rate of permanent stoma formation was significantly higher in the emergent-surgery group than in the SEMS group (p = 0.030), although the median hospital stay and overall complication rate were comparable. ...

Research paper thumbnail of Predictive Factors for Lymph Node Metastasis in Submucosal Invasive Colorectal Carcinoma: A New Proposal of Depth of Invasion for Radical Surgery

World journal of surgery, Aug 19, 2018

Patients with lymph node metastasis (LNM) in submucosal invasive colorectal carcinoma (SM cancer)... more Patients with lymph node metastasis (LNM) in submucosal invasive colorectal carcinoma (SM cancer) require additional surgical treatment after endoscopic dissection. However, because additional radical resection after endoscopic local resection may be unnecessary for cases without LNM, more specific criteria are required in order to diminish the incidence of further radical resection after endoscopic dissection. A total of 492 patients with biopsy-proven SM cancer who underwent curative surgery between January 2008 and December 2012 were collected and were divided into LNM group and no LNM group. The cutoff value for the depth of submucosal invasion was analyzed by a receiver operating characteristic (ROC) curve. In this retrospective study, the association between LNM and clinicopathologic factors was analyzed by logistic regression analysis. The depth of submucosal invasion of 1900 μm was determined as the cutoff value by ROC curve. Significant, independent predictive factors for L...

Research paper thumbnail of Factors affecting pouch-related outcomes after restorative proctocolectomy

PloS one, 2017

Restorative proctocolectomy (RPC) with ileal pouch anal anastomosis (IPAA) is the procedure of ch... more Restorative proctocolectomy (RPC) with ileal pouch anal anastomosis (IPAA) is the procedure of choice for patients with familial adenomatous polyposis (FAP) and ulcerative colitis (UC) despite morbidities that can lead to pouch failure. We aimed to identify factors associated with pouch-related morbidities. A retrospective analysis of patients who underwent RPC with IPAA was performed. To investigate the factors associated with pouch-related morbidities, patients' preoperative demographic and clinical factors, and intraoperative factors were included in the analysis. A total of 49 patients with UC, FAP, and colorectal cancer were included. Twenty patients (40.8%) experienced leakage-related, functional, and/or pouchitis-related morbidities. Patients with American Society of Anesthesiologists (ASA) grade 2 or 3 had a higher risk of functional morbidity than those with grade 1. Intraoperative blood loss exceeding 300.0 mL was associated with an increased risk of pouchitis-related ...

Research paper thumbnail of Totally Extraperitoneal Single Incision Laparoscopic Repair of Spigelian Hernia: Technical Notes

Journal of Laparoendoscopic & Advanced Surgical Techniques Part B, Videoscopy

Research paper thumbnail of Role of adjuvant chemotherapy in locally advanced rectal cancer with ypT0-3N0 after preoperative chemoradiation therapy and surgery

BMC Cancer

Background: We aimed to explore the clinical benefit of adjuvant chemotherapy (AC) with fluoropyr... more Background: We aimed to explore the clinical benefit of adjuvant chemotherapy (AC) with fluoropyrimidine in patients with ypT0-3N0 rectal cancer after preoperative chemoradiation therapy (CRT) followed by total mesorectal excision (TME). Methods: Patients with ypT0-3N0 rectal cancer after preoperative CRT and TME were included using prospectively collected tumor registry cohort between January 2001 and December 2013. Patients were categorized into two groups according to the receipt of AC. Disease-free survival (DFS) and overall survival (OS) were compared between the adjuvant and observation groups. To control for potential confounding factors, we also calculated propensity scores and performed propensity score-matched analysis for DFS and OS. Results: Of the 339 evaluated patients, 87 patients (25.7%) did not receive AC. There were no differences in DFS (hazard ratio [HR], 0.921; 95% confidence interval [CI], 0.562-1.507; P = 0.742) and OS (HR, 0.835; 95% CI, 0.423-1.648; P = 0.603) between the adjuvant and observation groups. After propensity score matching, DFS (HR, 1.129; 95% CI, 0.626-2.035; P = 0.688) and OS (HR, 1.200; 95% CI, 0.539-2.669; P = 0.655) did not differ between the adjuvant and observation groups. Advanced T stage and positive resection margin were independently associated with inferior DFS and OS on multivariate analysis. Conclusions: AC did not improve DFS and OS for patients with ypT0-3N0 rectal cancer after preoperative CRT followed by TME in this cohort study. The confirmative role of AC in locally advanced rectal cancer should be evaluated in prospective randomized trials with a larger sample size.

Research paper thumbnail of Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy for appendiceal and colorectal cancer with peritoneal carcinomatosis

Research paper thumbnail of Which Patients with Isolated Para-Aortic Lymph Node Metastasis Will Truly Benefit from Extended Lymph Node Dissection for Colon Cancer?

Cancer research and treatment : official journal of Korean Cancer Association, Jan 14, 2017

The prognosis of patients with colon cancer and para-aortic lymph node metastasis (PALNM) is poor... more The prognosis of patients with colon cancer and para-aortic lymph node metastasis (PALNM) is poor. We analyzed the prognostic factors of extramesenteric lymphadenectomy for colon cancer patients with isolated PALNM. We retrospectively reviewed 49 patients with PALNM who underwent curative resection between October 1988 and December 2009. In univariate analyses, the 5-year OS and DFS rates were higher in patients with ≤ 7 positive PALN (36.5% and 27.5%) than in those with > 7 PALN (14.3% and 14.3%; P = 0.010 and P = 0.027), respectively, and preoperative carcinoembryonic antigen (CEA) level > 5 was also correlated with a lower 5-year OS and DFS rate of 21.5% and 11.7% compared with those with CEA ≤ 5 (46.3% and 41.4%, P = 0.122 and 0.039, respectively). Multivariate analysis found that the number of positive PALN (hazard ratio [HR], 3.291; 95% confidence interval [CI], 1.309-8.275, P = 0.011) was an independent prognostic factor for OS and the number of positive PALN (HR, 2.484...

Research paper thumbnail of Rectal Mucinous Adenocarcinoma: MR Imaging Assessment of Response to Concurrent Chemotherapy and Radiation Therapy-A Hypothesis-generating Study

Radiology, Oct 18, 2017

Purpose To develop a system for assessment of tumor regression grade (TRG) with magnetic resonanc... more Purpose To develop a system for assessment of tumor regression grade (TRG) with magnetic resonance (MR) imaging that is applicable to rectal mucinous adenocarcinoma (RMAC) and to obtain a preliminary evaluation of the association of MR imaging assessment of TRG with response to preoperative concurrent chemotherapy and radiation therapy (CCRT). Materials and Methods This retrospective study was approved by the institutional review board, and informed consent was waived. Pre- and post-CCRT MR images of 59 patients with RMAC (median age, 59 years; range, 29-80 years; 42 men [median age, 59 years; range, 36-80 years] and 17 women [median age, 57 years; range, 29-79 years]) who underwent CCRT and subsequent elective resection from July 2005 to June 2015 were analyzed. Two experienced gastrointestinal radiologists independently analyzed imaging parameters such as T stage, mesorectal fascia status, extramural vascular invasion status, and TRG by using modified criteria developed for assess...

Research paper thumbnail of Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy for appendiceal and colorectal cancer with peritoneal carcinomatosis: Clinical outcomes at 2 tertiary referral centers in Korea

Medicine, 2017

Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) is regarded as... more Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) is regarded as effective surgical treatments in patients with peritoneal metastasis. This study aimed to evaluate the clinical outcomes of CRS and HIPEC in patients with appendiceal or colorectal cancer with peritoneal carcinomatosis.A total of 66 patients who underwent CRS with HIPEC for appendiceal or colorectal cancer with peritoneal metastasis at 2 tertiary referral centers in Korea were evaluated between July 2014 and March 2016. The perioperative outcomes and postoperative complications were evaluated prospectively.The mean peritoneal cancer index (PCI) was 15.3 ± 10.5. The distributions thereof were as follows: PCI < 10, 33.3%; PCI 10-19, 36.4%; and PCI≥20, 30.3%. Regarding completeness of cytoreduction (CC), 59.1% of patients achieved CC-0, with 18.2% showing CC-1 and 22.7% showing CC-2. The mean operation time was 9.4 hours, and the mean hospital stay was 20.2 days. The overall rate of sho...

Research paper thumbnail of Transanal Endoscopic Operation Versus Conventional Transanal Excision for Rectal Tumors: Case-Matched Study with Propensity Score Matching

World Journal of Surgery, 2017

Although transanal endoscopic surgery is practiced worldwide, there is no consensus on comparativ... more Although transanal endoscopic surgery is practiced worldwide, there is no consensus on comparative outcomes between transanal endoscopic operation (TEO) and transanal excision (TAE). In this study, we reviewed our experiences with these techniques and compared patients who underwent TEO and TAE using propensity score matching (PSM). A total of 207 patients underwent local rectal tumor excision between January 2008 and November 2015. To overcome selection bias, we used PSM to achieve a one-to-one TEO: TAE ratio. We included baseline characteristics, age, sex, surgeon, American Society of Anesthesiologists score, tumor location (clockwise direction), involved circumference quadrants, tumor size, and pathology. After PSM, 72 patients were included in each group. The tumor distance from the anal verge was higher in the TEO group (8.0 [5-10] vs. TAE: 4.0 [3-5], p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001). Complication rates did not differ between the groups (TEO: 8.3% vs. TAE: 11.1%, p = 0.39). TEO was associated with a shorter hospital stay (3.01 vs. 4.68 days, p = 0.001), higher negative margin rate (95.8 vs. 86.1%, p = 0.039), and non-fragmented specimen rate vs. TAE (98.6 vs. 90.3%, p = 0.029). TEO was more beneficial for patients with higher rectal tumors. Regardless of tumor location, involved circumference quadrants, and tumor size, TEO may more effectively achieve negative resection margins and non-fragmented specimens. Consequently, although local excision method according to tumor distance may be important, TEO will become the standard for rectal tumors.

Research paper thumbnail of Safety and Efficacy of Single-Incision Laparoscopic Totally Extraperitoneal Inguinal Hernia Repair: Comparative Study with Conventional Laparoscopic Totally Extraperitoneal Inguinal Hernia Repair

Journal of laparoendoscopic & advanced surgical techniques. Part A, 2017

Inguinal hernia is a common disease treated with diverse methods. Nowadays, laparoscopic totally ... more Inguinal hernia is a common disease treated with diverse methods. Nowadays, laparoscopic totally extraperitoneal approach is gaining its validity and shows favorable outcomes. However, single-incision laparoscopic surgery is also widening its applicable fields as a new technique. This study aimed to find whether single-incision laparoscopic total extraperitoneal inguinal hernia repair (SILTEP) is applicable compared to conventional laparoscopic total extraperitoneal hernia repair (CLTEP). We retrospectively reviewed 120 cases of SILTEP and 60 cases of CLTEP in Yonsei University Severance Hospital from January 2012 to December 2013. Each group was compared with patients' characteristics, operative details, and postoperative complications. There were no statistical difference in patient age, sex, body mass index, American Society of Anesthesiologists score, hernia type, or location between SILTEP and CLTEP. In operative details, operation time (61.77 ± 16.48 minutes versus 77.83 ±...

Research paper thumbnail of Laparoscopic-Assisted Versus Open Complete Mesocolic Excision and Central Vascular Ligation for Right-Sided Colon Cancer

Annals of Surgical Oncology, Mar 7, 2014

A concept of complete mesocolic excision (CME) and central vascular ligation for colonic cancer h... more A concept of complete mesocolic excision (CME) and central vascular ligation for colonic cancer has been recently introduced. The aim of this study was to evaluate and compare perioperative and oncologic outcomes after laparoscopic-assisted CME (LCME) and open CME (OCME) for right-sided colon cancers. The study group included 128 patients who underwent an LCME and 137 patients who underwent an OCME for right-sided colon cancer between June 2006 and December 2008. The propensity scoring matching for sex, body mass index, tumor location, and pathologic T and TNM stage produced 85 matched pairs. The median time to soft diet (LCME 6 days vs. OCME 7 days, p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001) and the possible length of stay (7 vs. 13 days, p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001) were significantly shorter in the laparoscopic group. The median operation time (179 vs. 194 minutes, p = 0.862) and number of harvested lymph nodes (27 vs. 28, p = 0.337) were comparable between groups. The morbidity within 30 days after surgery was comparable between the groups (12.9 vs. 24.7 %, p = 0.050). The 5-year overall survival rates of the OCME and LCME groups were 77.8 and 90.3 % (p = 0.028), and the 5-year disease-free survival rates were 71.8 and 83.3 % (p = 0.578), respectively. Herein, we demonstrated the feasibility and safety of LCME for right-sided colon cancer, and in terms of better short-term outcomes, LCME was more advantageous than OCME. Although LCME for right-sided colon cancer was associated with better 5-year overall survival, compared with an open approach, the long-term oncologic outcomes between the groups were…

Research paper thumbnail of Comprehensive Immuno-Molecular Profiles for Liposarcoma: Roles of Programmed Death Ligand 1, Microsatellite Instability, and PIK3CA

Oncology

Background: Developing personalized strategies for cancer has shown good efficacies. Methods: We ... more Background: Developing personalized strategies for cancer has shown good efficacies. Methods: We assessed the molecular targets programmed death ligand 1 (PD-L1), microsatellite instability (MSI), and PIK3CA. Seventy-four patients with liposarcomas who underwent curative resection were assessed for PD-L1 expression in the tumor and tumor-infiltrating lymphocytes (TILs), mismatch repair proteins (MLH1, PMS2, MSH2, and MSH6) by immunohistochemistry, MSI using polymerase chain reaction, and PIK3CA mutation/amplification using pyrosequencing and fluorescence in situ hybridization. Results: Seventeen (23%) cases were TIL+ (≥1 + expression) and associated with longer 5-year overall survival than those with TIL– tumors (84.4 vs. 60.8%, p = 0.007). Six (35.3%) PD-L1+ tumors were detected only in TIL+ cases, with none detected in tumor cells. Two well-differentiated liposarcomas showed MSI, one low and one high with concurrent loss of MLH1, MSH6, and PMS2. PIK3CA mutation was detected in 7 (...

Research paper thumbnail of Late anastomotic leakage after anal sphincter saving surgery for rectal cancer: is it different from early anastomotic leakage?

International Journal of Colorectal Disease

Research paper thumbnail of Transanal Total Mesorectal Excision for Rectal Cancer: Perioperative and Oncological Outcomes

Research paper thumbnail of Cost analysis of single-incision versus conventional laparoscopic surgery for colon cancer: A propensity score-matching analysis

Research paper thumbnail of Impact of tumor sidedness on survival and recurrence patterns in colon cancer patients

Annals of Surgical Treatment and Research

Previous studies have reported conflicting results regarding the prognostic value of tumor sidedn... more Previous studies have reported conflicting results regarding the prognostic value of tumor sidedness in colon cancer. We investigated the oncologic impact of tumor location and examined whether recurrence patterns were related to tumor sidedness in colon cancer patients. Methods: We identified stage I-III colon adenocarcinoma patients from a prospective colorectal cancer registry at Severance Hospital, Seoul, Korea, who underwent complete mesocolic excision between 2005 and 2012. Adjusted hazard ratios (HRs) and 95% confidence intervals (CI) for predictors of cancer-specific survival (CSS), recurrence-free survival (RFS), and cumulative recurrence at specific anatomic sites were examined using Cox proportional hazard regression analysis. Results: Overall, 1,912 patients, 1,077 (56.3%) with left-sided colon cancer (LCC), and 835 (43.7%) with right-sided colon cancer (RCC), at a median follow-up of 59 months, were eligible and included in the study. In univariate analysis, similar 5-year CSS and RFS were observed for LCC and RCC in the total patient population, and when stratified by stage for stage I and II patients. For stage III patients, an adjusted Cox regression analysis indicated that RCC patients had a higher risk of cancer-specific mortality (HR, 1.75; 95% CI, 1.07-2.86; P = 0.024) and recurrence (HR, 1.78; 95% CI, 1.22-2.60; P = 0.003). Furthermore, RCC was an independent predictor of peritoneal recurrence (HR, 1.86; 95% CI, 1.05-3.29; P = 0.031) in stage III patients. Conclusion: RCC correlated with worse CSS and RFS than LCC. In stage III patients, RCC correlated with increased risk of peritoneal recurrence. The reasons for these differences remain to be investigated.

Research paper thumbnail of Characteristics and Survival of Korean Patients With Colorectal Cancer Based on Data From the Korea Central Cancer Registry Data

Annals of coloproctology, 2018

The incidence of colorectal cancer (CRC) in Korea has increased remarkably during the past few de... more The incidence of colorectal cancer (CRC) in Korea has increased remarkably during the past few decades. The present study investigated the characteristics and survival of patients with CRC in Korea as a function of time, tumor distribution, stage, sex, and age. We retrieved clinical data on 326,712 CRC patients diagnosed between 1996 and 2015 from the Korea Central Cancer Registry. The incidence and the 5-year relative survival rates were compared across time period, tumor distribution, stage, sex, and age group. The percentage of patients with colon cancer increased from 49.5% in 1996-2000 to 66.4% in 2011-2015 while the percentage of patients with rectal cancer decreased from 50.5% to 33.6%. The 5-year relative survival rates for all CRCs improved from 58.7% in 1996-2000 to 75.0% in 2011-2015. For 1996-2000, survival rates were highest for patients with left-sided colon cancers, followed by those with right-sided, transverse, rectal, rectosigmoid cancers. For 2011-2015, the surviv...

Research paper thumbnail of Differences in the Efficacies of Pazopanib and Gemcitabine/Docetaxel as Second-Line Treatments for Metastatic Soft Tissue Sarcoma

Oncology, Jan 18, 2018

We retrospectively investigated the treatment outcomes of second-line treatment with pazopanib or... more We retrospectively investigated the treatment outcomes of second-line treatment with pazopanib or gemcitabine/docetaxel in patients with advanced soft tissue sarcoma (STS). Ninety-one patients who were treated with pazopanib or gemcitabine/docetaxel for advanced STS between 1995 and 2015 were analyzed. Forty-six and 45 patients received pazopanib and gemcitabine/docetaxel, respectively. The median progression-free survival for the group treated with pazopanib was 4.5 months compared with 3.0 months for the gemcitabine/docetaxel group (p = 0.593). The median overall survival for the group treated with pazopanib was 12.6 months compared with 14.2 months for the gemcitabine/docetaxel group (p = 0.362). The overall response rates (ORRs) were 6.5 and 26.7% in the pazopanib and gemcitabine/docetaxel groups, respectively. The following parameters had ORRs favoring gemcitabine/docetaxel: age ≥50 years (31.6 vs. 2.9%, p = 0.006), histologic grade 1-2 (40.9 vs. 0%, p = 0.001), and poor first-...

Research paper thumbnail of Temporal changes in immune cell composition and cytokines in response to chemoradiation in rectal cancer

Scientific reports, Jan 15, 2018

We measured systemic changes in the immune response in 92 patients receiving preoperative chemora... more We measured systemic changes in the immune response in 92 patients receiving preoperative chemoradiation therapy (CRT) and subsequent surgery for rectal cancer. The peripheral blood was sampled five times from the onset of CRT until surgery. Lymphocytes decreased continuously during CRT but increased after CRT. The increased lymphocyte population was predominantly CD8+ T lymphocytes, which accounted for a significantly larger proportion in patients without residual lymph node metastasis than in those with residual lymph node metastasis. Neutrophils and monocytes decreased during the initial two weeks of CRT but were maintained or increased afterwards. Neutrophil and monocyte counts were significantly lower in patients with a pCR (pathologic complete response) than in those without a pCR two weeks after CRT began but not at the initiation of CRT. All cytokines showed dramatic changes one month after the termination of CRT. Cytokines related to the antitumour immune response increased...

Research paper thumbnail of Long-term outcomes after stenting as a bridge to surgery in patients with obstructing left-sided colorectal cancer

International journal of colorectal disease, Jan 12, 2018

Self-expandable metallic stents (SEMS) may be used in acute, obstructing, left-sided colorectal c... more Self-expandable metallic stents (SEMS) may be used in acute, obstructing, left-sided colorectal cancer (CRC) to avoid high-risk emergency surgery. However, the data regarding the long-term effects of SEMS as a bridge to surgery are limited and contradictory. Our aim is to analyze the long-term oncological outcomes of SEMS compared with surgery. Between January 2006 and November 2013, a total of 855 patients with stage III CRC were regularly followed at the CRC clinic of Severance Hospital, Seoul, Korea. We retrospectively evaluated their 5-year disease-free survival (DFS), 5-year overall survival (OS), and 5-year cancer-specific survival (CSS). There were 94 patients in the SEMS group, 17 in the emergent-surgery group, and 744 in the elective-surgery group. In the short term, the rate of permanent stoma formation was significantly higher in the emergent-surgery group than in the SEMS group (p = 0.030), although the median hospital stay and overall complication rate were comparable. ...

Research paper thumbnail of Predictive Factors for Lymph Node Metastasis in Submucosal Invasive Colorectal Carcinoma: A New Proposal of Depth of Invasion for Radical Surgery

World journal of surgery, Aug 19, 2018

Patients with lymph node metastasis (LNM) in submucosal invasive colorectal carcinoma (SM cancer)... more Patients with lymph node metastasis (LNM) in submucosal invasive colorectal carcinoma (SM cancer) require additional surgical treatment after endoscopic dissection. However, because additional radical resection after endoscopic local resection may be unnecessary for cases without LNM, more specific criteria are required in order to diminish the incidence of further radical resection after endoscopic dissection. A total of 492 patients with biopsy-proven SM cancer who underwent curative surgery between January 2008 and December 2012 were collected and were divided into LNM group and no LNM group. The cutoff value for the depth of submucosal invasion was analyzed by a receiver operating characteristic (ROC) curve. In this retrospective study, the association between LNM and clinicopathologic factors was analyzed by logistic regression analysis. The depth of submucosal invasion of 1900 μm was determined as the cutoff value by ROC curve. Significant, independent predictive factors for L...

Research paper thumbnail of Factors affecting pouch-related outcomes after restorative proctocolectomy

PloS one, 2017

Restorative proctocolectomy (RPC) with ileal pouch anal anastomosis (IPAA) is the procedure of ch... more Restorative proctocolectomy (RPC) with ileal pouch anal anastomosis (IPAA) is the procedure of choice for patients with familial adenomatous polyposis (FAP) and ulcerative colitis (UC) despite morbidities that can lead to pouch failure. We aimed to identify factors associated with pouch-related morbidities. A retrospective analysis of patients who underwent RPC with IPAA was performed. To investigate the factors associated with pouch-related morbidities, patients' preoperative demographic and clinical factors, and intraoperative factors were included in the analysis. A total of 49 patients with UC, FAP, and colorectal cancer were included. Twenty patients (40.8%) experienced leakage-related, functional, and/or pouchitis-related morbidities. Patients with American Society of Anesthesiologists (ASA) grade 2 or 3 had a higher risk of functional morbidity than those with grade 1. Intraoperative blood loss exceeding 300.0 mL was associated with an increased risk of pouchitis-related ...

Research paper thumbnail of Totally Extraperitoneal Single Incision Laparoscopic Repair of Spigelian Hernia: Technical Notes

Journal of Laparoendoscopic & Advanced Surgical Techniques Part B, Videoscopy

Research paper thumbnail of Role of adjuvant chemotherapy in locally advanced rectal cancer with ypT0-3N0 after preoperative chemoradiation therapy and surgery

BMC Cancer

Background: We aimed to explore the clinical benefit of adjuvant chemotherapy (AC) with fluoropyr... more Background: We aimed to explore the clinical benefit of adjuvant chemotherapy (AC) with fluoropyrimidine in patients with ypT0-3N0 rectal cancer after preoperative chemoradiation therapy (CRT) followed by total mesorectal excision (TME). Methods: Patients with ypT0-3N0 rectal cancer after preoperative CRT and TME were included using prospectively collected tumor registry cohort between January 2001 and December 2013. Patients were categorized into two groups according to the receipt of AC. Disease-free survival (DFS) and overall survival (OS) were compared between the adjuvant and observation groups. To control for potential confounding factors, we also calculated propensity scores and performed propensity score-matched analysis for DFS and OS. Results: Of the 339 evaluated patients, 87 patients (25.7%) did not receive AC. There were no differences in DFS (hazard ratio [HR], 0.921; 95% confidence interval [CI], 0.562-1.507; P = 0.742) and OS (HR, 0.835; 95% CI, 0.423-1.648; P = 0.603) between the adjuvant and observation groups. After propensity score matching, DFS (HR, 1.129; 95% CI, 0.626-2.035; P = 0.688) and OS (HR, 1.200; 95% CI, 0.539-2.669; P = 0.655) did not differ between the adjuvant and observation groups. Advanced T stage and positive resection margin were independently associated with inferior DFS and OS on multivariate analysis. Conclusions: AC did not improve DFS and OS for patients with ypT0-3N0 rectal cancer after preoperative CRT followed by TME in this cohort study. The confirmative role of AC in locally advanced rectal cancer should be evaluated in prospective randomized trials with a larger sample size.

Research paper thumbnail of Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy for appendiceal and colorectal cancer with peritoneal carcinomatosis

Research paper thumbnail of Which Patients with Isolated Para-Aortic Lymph Node Metastasis Will Truly Benefit from Extended Lymph Node Dissection for Colon Cancer?

Cancer research and treatment : official journal of Korean Cancer Association, Jan 14, 2017

The prognosis of patients with colon cancer and para-aortic lymph node metastasis (PALNM) is poor... more The prognosis of patients with colon cancer and para-aortic lymph node metastasis (PALNM) is poor. We analyzed the prognostic factors of extramesenteric lymphadenectomy for colon cancer patients with isolated PALNM. We retrospectively reviewed 49 patients with PALNM who underwent curative resection between October 1988 and December 2009. In univariate analyses, the 5-year OS and DFS rates were higher in patients with ≤ 7 positive PALN (36.5% and 27.5%) than in those with > 7 PALN (14.3% and 14.3%; P = 0.010 and P = 0.027), respectively, and preoperative carcinoembryonic antigen (CEA) level > 5 was also correlated with a lower 5-year OS and DFS rate of 21.5% and 11.7% compared with those with CEA ≤ 5 (46.3% and 41.4%, P = 0.122 and 0.039, respectively). Multivariate analysis found that the number of positive PALN (hazard ratio [HR], 3.291; 95% confidence interval [CI], 1.309-8.275, P = 0.011) was an independent prognostic factor for OS and the number of positive PALN (HR, 2.484...

Research paper thumbnail of Rectal Mucinous Adenocarcinoma: MR Imaging Assessment of Response to Concurrent Chemotherapy and Radiation Therapy-A Hypothesis-generating Study

Radiology, Oct 18, 2017

Purpose To develop a system for assessment of tumor regression grade (TRG) with magnetic resonanc... more Purpose To develop a system for assessment of tumor regression grade (TRG) with magnetic resonance (MR) imaging that is applicable to rectal mucinous adenocarcinoma (RMAC) and to obtain a preliminary evaluation of the association of MR imaging assessment of TRG with response to preoperative concurrent chemotherapy and radiation therapy (CCRT). Materials and Methods This retrospective study was approved by the institutional review board, and informed consent was waived. Pre- and post-CCRT MR images of 59 patients with RMAC (median age, 59 years; range, 29-80 years; 42 men [median age, 59 years; range, 36-80 years] and 17 women [median age, 57 years; range, 29-79 years]) who underwent CCRT and subsequent elective resection from July 2005 to June 2015 were analyzed. Two experienced gastrointestinal radiologists independently analyzed imaging parameters such as T stage, mesorectal fascia status, extramural vascular invasion status, and TRG by using modified criteria developed for assess...

Research paper thumbnail of Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy for appendiceal and colorectal cancer with peritoneal carcinomatosis: Clinical outcomes at 2 tertiary referral centers in Korea

Medicine, 2017

Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) is regarded as... more Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) is regarded as effective surgical treatments in patients with peritoneal metastasis. This study aimed to evaluate the clinical outcomes of CRS and HIPEC in patients with appendiceal or colorectal cancer with peritoneal carcinomatosis.A total of 66 patients who underwent CRS with HIPEC for appendiceal or colorectal cancer with peritoneal metastasis at 2 tertiary referral centers in Korea were evaluated between July 2014 and March 2016. The perioperative outcomes and postoperative complications were evaluated prospectively.The mean peritoneal cancer index (PCI) was 15.3 ± 10.5. The distributions thereof were as follows: PCI < 10, 33.3%; PCI 10-19, 36.4%; and PCI≥20, 30.3%. Regarding completeness of cytoreduction (CC), 59.1% of patients achieved CC-0, with 18.2% showing CC-1 and 22.7% showing CC-2. The mean operation time was 9.4 hours, and the mean hospital stay was 20.2 days. The overall rate of sho...

Research paper thumbnail of Transanal Endoscopic Operation Versus Conventional Transanal Excision for Rectal Tumors: Case-Matched Study with Propensity Score Matching

World Journal of Surgery, 2017

Although transanal endoscopic surgery is practiced worldwide, there is no consensus on comparativ... more Although transanal endoscopic surgery is practiced worldwide, there is no consensus on comparative outcomes between transanal endoscopic operation (TEO) and transanal excision (TAE). In this study, we reviewed our experiences with these techniques and compared patients who underwent TEO and TAE using propensity score matching (PSM). A total of 207 patients underwent local rectal tumor excision between January 2008 and November 2015. To overcome selection bias, we used PSM to achieve a one-to-one TEO: TAE ratio. We included baseline characteristics, age, sex, surgeon, American Society of Anesthesiologists score, tumor location (clockwise direction), involved circumference quadrants, tumor size, and pathology. After PSM, 72 patients were included in each group. The tumor distance from the anal verge was higher in the TEO group (8.0 [5-10] vs. TAE: 4.0 [3-5], p &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001). Complication rates did not differ between the groups (TEO: 8.3% vs. TAE: 11.1%, p = 0.39). TEO was associated with a shorter hospital stay (3.01 vs. 4.68 days, p = 0.001), higher negative margin rate (95.8 vs. 86.1%, p = 0.039), and non-fragmented specimen rate vs. TAE (98.6 vs. 90.3%, p = 0.029). TEO was more beneficial for patients with higher rectal tumors. Regardless of tumor location, involved circumference quadrants, and tumor size, TEO may more effectively achieve negative resection margins and non-fragmented specimens. Consequently, although local excision method according to tumor distance may be important, TEO will become the standard for rectal tumors.

Research paper thumbnail of Safety and Efficacy of Single-Incision Laparoscopic Totally Extraperitoneal Inguinal Hernia Repair: Comparative Study with Conventional Laparoscopic Totally Extraperitoneal Inguinal Hernia Repair

Journal of laparoendoscopic & advanced surgical techniques. Part A, 2017

Inguinal hernia is a common disease treated with diverse methods. Nowadays, laparoscopic totally ... more Inguinal hernia is a common disease treated with diverse methods. Nowadays, laparoscopic totally extraperitoneal approach is gaining its validity and shows favorable outcomes. However, single-incision laparoscopic surgery is also widening its applicable fields as a new technique. This study aimed to find whether single-incision laparoscopic total extraperitoneal inguinal hernia repair (SILTEP) is applicable compared to conventional laparoscopic total extraperitoneal hernia repair (CLTEP). We retrospectively reviewed 120 cases of SILTEP and 60 cases of CLTEP in Yonsei University Severance Hospital from January 2012 to December 2013. Each group was compared with patients' characteristics, operative details, and postoperative complications. There were no statistical difference in patient age, sex, body mass index, American Society of Anesthesiologists score, hernia type, or location between SILTEP and CLTEP. In operative details, operation time (61.77 ± 16.48 minutes versus 77.83 ±...