Yukihiro Hama | National Defense Medical College (original) (raw)

Papers by Yukihiro Hama

Asian Journal of Surgery, Mar 1, 2018

Background: Trimodality therapy with surgery and neoadjuvant chemoradiotherapy (nCRT) has been de... more Background: Trimodality therapy with surgery and neoadjuvant chemoradiotherapy (nCRT) has been developed to improve survival outcomes in advanced esophageal cancer. We hypothesized that the effect of surgery plus nCRT with oral fluoropyrimidine (S-1) and lowdose cisplatin will be effective with low toxic effects in patients with esophageal cancer as well as gastric cancer. Methods: This cohort study included 28 Japanese patients who underwent nCRT plus esophagectomy for esophageal cancer in preoperative clinical Stage II/III. They received only one cycle of S-1 and low-dose cisplatin concurrently, followed by surgery 3e4 weeks after completion of nCRT (the doses of radiotherapy were 20 or 30 Gy). We examined the clinical efficacy and safety of nCRT plus esophagectomy. Results: All patients had squamous cell carcinoma and they all completed nCRT and underwent esophagectomy. No treatment-related deaths were observed. The response rate to nCRT was 92.9%. The 1-year, 3-year, and 5-year overall survival rates were 84.4%, 67.0%, and 67.0%, respectively for Stage II/III.

Klinická onkologie, Oct 15, 2021

Background: Soft tissue tumors near metal implants are sometimes difficult to treat with real-tim... more Background: Soft tissue tumors near metal implants are sometimes difficult to treat with real-time image-guided radiation therapy. Low-field MRI was utilized to clearly delineate the tumor and spinal cord while avoiding metal artifacts, and re-irradiation was performed for recurrent spinal metastases. Case description: A 57-year-old woman with a history of thyroid cancer was referred for re-irradiation for recurrent painful bone metastases in the thoracolumbar spine. She had already undergone conventional radiation therapy followed by stereotactic ablative radiotherapy and multiple fusion surgeries. Since the radiation dose to the spinal cord should have been limited, metal artifact-free low-field MRI-guided re-irradiation was performed with no significant adverse events. Conclusion: Low-field MRI-guided re-irradiation may be feasible for recurrent spinal metastases, even after metal implants have been placed.

Clinical Imaging, May 1, 2005

Carcinoid tumors arising from the ampulla of Vater are rare, and their magnetic resonance (MR) im... more Carcinoid tumors arising from the ampulla of Vater are rare, and their magnetic resonance (MR) imaging findings have not been reported in the literature to date. We report a case of carcinoid tumor of the ampulla of Vater and discuss the characteristic MR imaging findings. The tumor was isointense relative to the muscle on both the T1- and T2-weighted images with heterogeneous enhancement after gadolinium administration. Both the common bile and the pancreatic ducts were dilated on the MR cholangiopancreatography.

International Journal of Radiation Oncology Biology Physics, Oct 1, 2003

Clinical Imaging, Sep 1, 2005

Castleman's disease is a rare lymphoproliferative disorder of unknown etiology. To our knowledge,... more Castleman's disease is a rare lymphoproliferative disorder of unknown etiology. To our knowledge, Castleman's disease arising from the accessory spleen has not been reported in the literature. We report the case of localized Castleman's disease arising from the accessory spleen in a 34-year-old woman and discuss the characteristic findings of ultrasonography (US), computed tomography (CT), and magnetic resonance (MR) imaging.

Academic Radiology, May 1, 2014

Rationale and Objectives: Prostate calcification is a noninvasive landmark for daily positioning ... more Rationale and Objectives: Prostate calcification is a noninvasive landmark for daily positioning of image-guided radiation therapy. However, detectability of prostate calcification with megavoltage helical computed tomography (MVCT) has not been evaluated. The purpose of this study was to evaluate the detectability of prostate calcification and to investigate how to predict detectability of calcification with MVCT. Materials and Methods: Thirty patients with prostate cancer who were scheduled for helical tomotherapy were included in this study. The detectability of prostate calcification on MVCT was evaluated by comparing against kilovoltage multidetector-row CT (KVCT) as the standard of reference. Maximum signal intensity (SImax), area (A) of calcification, and the product of both (SImax$A) were compared between undetectable and detectable calcifications. Then, the threshold values of SImax, A, and SImax$A were decided to achieve 100% sensitivity on MVCT. Results: KVCT identified 49 calcifications in 28 of 30 patients. MVCT detected 19 (39%) of 49 calcifications in 15 (50%) of 30 patients. The minimum threshold values of SImax, A, and SImax$A to detect prostate calcifications were 953 HU, 20.98 mm 2 , and 7784 HU mm 2 , respectively. Using the threshold values of SImax, A, and SImax$A, 20% (10/49), 18% (9/49), and 35% (17/49) of calcifications were in the detection range, respectively. Conclusions: MVCT can depict about one-third of prostate calcifications detectable on KVCT. The product of maximum signal intensity and area of calcification is the most distinguishable index for predicting patients showing prostate calcifications on MVCT.

Japanese Journal of Clinical Oncology, Mar 4, 2008

Using integrated 18 F-fluorodeoxyglucose positron emission tomography/computed tomography fusion ... more Using integrated 18 F-fluorodeoxyglucose positron emission tomography/computed tomography fusion imaging (18 F-FDG PET/CT), the clinical significance of 18 F-FDG uptake was evaluated in patients with primary breast cancer. Methods: Clinicopathological correlation with the level of maximum standardized uptake values (SUV) 60 min obtained from preoperative 18 F-FDG PET/CT were examined in 152 patients with primary breast cancer. The prognostic impact of the level of SUV was explored using simulated prognosis derived from computed program Adjuvant! in 136 (89%) patients with invasive ductal carcinoma (IDC). Results: High SUV level was significantly correlated with tumor invasive size (2 cm) (P ,0.0001), higher score of nuclear grade (P ,0.0001), nuclear atypia (P ,0.0001) and mitosis counts (P ,0.0001), negative hormone receptor status (P ¼ 0.001), high score of c-erbB-2 expression (P ¼ 0.006), lymph node metastasis (P ¼ 0.002), and IDC in comparison with invasive lobular carcinoma (P ¼ 0.004). Multivariate analyses showed tumor invasive size, nuclear grade and estrogen receptor negativity were significantly correlated with SUV in primary breast cancer (P ,0.0001,,0.0001, and ,0.012, respectively), and nuclear grade was significantly correlated with SUV in tumors of invasive size 2 cm or less (P ,0.0001). Tumors with high SUV (cutoff value 4.0) showed higher relapse and mortality rate compared to those with low SUV (P ,0.0001). Conclusions: High uptake of 18 F-FDG would be predictive of poor prognosis in patients with primary breast cancer, and aggressive features of cancer cells in patients with early breast cancer. 18 F-FDG PET/CT could be a useful tool to pretherapeutically predict biological characteristics and baseline risk of breast cancer.

European Radiology, Dec 1, 2002

A 58-year-old man with an abscess of the psoas muscle was returned to our hospital with hematemes... more A 58-year-old man with an abscess of the psoas muscle was returned to our hospital with hematemesis. Two years earlier, he had undergone coil embolization for a superior mesenteric artery (SMA) pseudoaneurysm secondary to pancreatitis. Based on the physical examination, serum amylase level, and abdominal radiographs, a diagnosis of acute exacerbation of pancreatitis and coil compaction of the SMA pseudoaneurysm was made. The patient underwent re-embolization for the coil compaction using interlocking detachable coils. His condition improved gradually, and he was discharged 3 weeks later. To our knowledge, this is the first report of coil compaction of SMA pseudoaneurysm.

Minimally Invasive Therapy & Allied Technologies, 1999

... Radiology 1996; 201 : Klein GE, Szolar DH, Breinl E, Raith J, Schreyer HH. Endovascular treat... more ... Radiology 1996; 201 : Klein GE, Szolar DH, Breinl E, Raith J, Schreyer HH. Endovascular treatment of renal artery aneurysm with conventional non-detachable microcoils and Guglielmi detachable coils. ... Scand J Urol Nephrol 1 1 Helenon 0, el Rody F, Correas JM eta/. ...

International Journal of Clinical Oncology, Aug 1, 2009

A 62-year-old woman presented with right flank pain, and computed tomography (CT) showed bilatera... more A 62-year-old woman presented with right flank pain, and computed tomography (CT) showed bilateral adrenal tumors (right, 8 cm; left, 4 cm). There were no abnormal findings on physical examination, and adrenal hormone levels in serum and urine were within normal limits. Radiological studies showed a right adrenal tumor with intratumoral hemorrhage, a cystic tumor in the left adrenal gland, and no sign of distant metastasis. Because laboratory tests showed normal levels of adrenal hormones, we considered the tumors to be nonfunctioning adrenal tumors. The right adrenal tumor was surgically removed because it was thought to be malignant, and histological examination revealed that it was a leiomyosarcoma. Postoperative CT showed a pleural metastasis in the right chest wall. The patient received combination chemotherapy with cyclophosphamide, vincristine, adriamycin, and dacarbazine. The metastasis was also treated with radiofrequency ablation (RFA). Because the left adrenal tumor grew rapidly despite two courses of the chemotherapy, it too was surgically removed. After the operation, metastasis in the right iliac bone was treated with RFA and radiotherapy. Positron emission tomography detected bilateral femoral metastases, and these were treated with radiotherapy in combination with a low dose of cisplatin. A liver metastasis and a small metastasis in the left kidney were treated with RFA and a metastasis in the pancreatic tail was removed surgically. Sixteen months after the right adrenalectomy, the patient died due to systemic spread of the disease. Multiple local treatments including RFA, radiotherapy, and resection were effective for the local control of metastatic lesions of adrenal leiomyosarcoma.

Journal of Cancer Research and Therapeutics, 2022

Objectives MRI provides clear visualization of spinal cord, tumor, and bone for patient positioni... more Objectives MRI provides clear visualization of spinal cord, tumor, and bone for patient positioning and verification during MRI-guided radiotherapy (MRI-RT). Therefore, we wished to evaluate spine stereotactic ablative radiotherapy (SABR) feasibility with MRI-RT. Given dosimetric limitations of first generation Co-60 MRI-RT, we then evaluated improvements by newer linear accelerator (linac) MRI-RT. Methods Nine spinal metastases were treated with Co-60 MRI-RT. Seven received a single 16 Gy fraction, and two received three fractions totaling 24 or 30 Gy. After re-planning with linac MRI-RT software, comparisons of OAR and dose spillage objectives between Co-60 and linac plans were performed. Results Spinal cord and cauda equina dose constraints were met in all Co-60 cases. Treatments were delivered successfully with real-time imaging during treatment and no treatment-related toxicities. While limits for dose spillage into surrounding soft tissues were not achieved due to the limitations of the Co-60 system, this could be corrected with linac MRI-RT delivery. Conclusions MRI-RT SABR of spinal metastases is feasible with Co-60 MRI-RT. Dose delivery is improved by linac MRI-RT.

European Radiology, May 1, 2004

The aim of this study was to verify the feasibility of using a J-tipped guidewire as a target for... more The aim of this study was to verify the feasibility of using a J-tipped guidewire as a target for puncture of the subclavian artery in the placement of a reservoir port and catheter system (RPCS). Twenty-five patients with various hepatic malignancies underwent percutaneous implantation of an RPCS through the left subclavian artery for regional chemotherapy. To successfully puncture the left subclavian artery, a J-tipped guidewire was used as a target with fluoroscopic guidance. Technical success and complication rates, and numbers of puncture failures, were retrospectively analyzed. Implantation of the RPCS was successful in all patients. Eight (32%) patients had minor complications and no patient had major complications. The number of puncture failures per patient was 0 to 1 (mean=0.32). The J-tipped guidewire is a safe and appropriate target for puncture of the subclavian artery in the placement of an RPCS.

European Radiology, Jul 19, 2000

Minimally Invasive Therapy & Allied Technologies, 2005

A 70-year-old woman with advanced ureteral carcinoma was referred due to stenosis and occlusion o... more A 70-year-old woman with advanced ureteral carcinoma was referred due to stenosis and occlusion of the bilateral iliac veins and inferior vena cava after failure of radiation therapy. We successfully placed endovascular stents in the bilateral iliac veins and the inferior vena cava. The stents remain patent after five months of follow-up without requiring secondary intervention. As far as we know, this is the first report of radioresistant malignant stenosis of the bilateral iliac veins and the inferior vena cava that was successfully treated with stent placement.

Current Gynecologic Oncology, May 31, 2022

Magnetic resonance imaging-guided radiotherapy can accurately irradiate moving targets such as ce... more Magnetic resonance imaging-guided radiotherapy can accurately irradiate moving targets such as cervical cancer. An 82-year-old woman with locally advanced cervical cancer was referred for palliative radiotherapy. She had refused chemotherapy and brachytherapy, so she was treated with external beam radiotherapy to control her uterine bleeding and to alleviate pubic pain. Since her cervical cancer had no metastases, and she was expected to survive for a long time, curative doses of radiation (70-80 Gy/ 28 fractions) were administered by magnetic resonance imaging-guided planned adaptive intensity-modulated radiation therapy. Six months after intensity-modulated radiation therapy, the tumor disappeared without adverse events, and her symptoms were relieved. To the best of our knowledge, this is the first report of locally advanced cervical cancer treated with high-dose magnetic resonance imaging-guided adaptive intensity-modulated radiation therapy.

Clinical Rheumatology, Nov 15, 2006

Polyarteritis nodosa (PN) occasionally develops in association with malignant disorders. A 71-yea... more Polyarteritis nodosa (PN) occasionally develops in association with malignant disorders. A 71-year-old man suddenly suffered from bleeding due to the rupture of a hepatic artery aneurysm. The ruptured lesion was embolized endovascularly by coiling, and the bleeding was stopped. A biopsy of the right inguinal lymph node demonstrated angioimmunoblastic T cell lymphoma (AITL). He received immunosuppressive treatment with transient response, although he relapsed 4 months later. To our knowledge, this is the first case of which PN was associated with AITL.

Surgical Neurology, Sep 1, 1999

The purpose of this study was to define the feasibility, the efficacy and the safety of preoperat... more The purpose of this study was to define the feasibility, the efficacy and the safety of preoperative embolization (POE) of meningiomas using polyvinyl alcohol (PVA) particles. Materials and methods: Between January 2006 and June 2014, 191 consecutive patients were referred to our institution for the treatment of meningiomas; of these 57 patients were excluded from the study. A total of 64 patients (22 men and 42 women) with a mean age of 58.4 ± 10.8 [SD] years (range: 14-82 years) who underwent POE with PVA particles, achieving extensive (> 90%) devascularization were ultimately included and compared to 70 patients who had surgery without POE. Surgical time and intraoperative blood loss were compared between the two groups. The duration of procedures and complications related to POE were analyzed. Results: No differences were found between the two groups with respect to intraoperative blood loss. A significant reduction in surgical time was observed for the group who had POE (207.4 ± 79.5 [SD] min vs. 226.9 ± 117.6 [SD] min; P = 0.028). In a subgroup analysis, the size and location of meningiomas did not influence these results. The duration of procedures was

Research Square (Research Square), Jul 30, 2021

Radical radiation therapy for oligorecurrent prostate cancer is considered to improve both overal... more Radical radiation therapy for oligorecurrent prostate cancer is considered to improve both overall and disease-speci c survival. Therefore, accurate diagnosis by imaging is important when considering the indications for radiation therapy. We present a case of marginal recurrence of bone metastases from castration-resistant prostate cancer previously treated with radical radiation therapy, which could not be detected by bone single photon emission computed tomography/computed tomography (SPECT/CT) but could be diagnosed by 68Ga-prostate-speci c membrane antigen positron emission tomography/computed tomography (68Ga-PSMA PET/CT). Bone SPECT/CT showed false-positive tracer uptake in the lesion previously irradiated. 68Ga-PSMA PET/CT scan showed no abnormal uptake in the previously irradiated lesion, but showed intense uptake in the newly developed metastasis near the irradiated site. 68Ga-PSMA PET/CT scan may be able to diagnose marginal recurrence after radiation therapy more accurately than bone SPECT/CT.

Acta Radiologica, Jan 7, 2010

A 61-year-old man, with pseudoaneurysm of the superior mesenteric artery presenting with gastroin... more A 61-year-old man, with pseudoaneurysm of the superior mesenteric artery presenting with gastrointestinal bleeding, was successfully treated by transcatheter embolization using interlocking detachable coils. During the following observation time of 10 months, the patient had no sign of gastrointestinal bleeding. We underline the importance and feasibility of transcatheter embolization as the first-line treatment in such pseudoaneurysms.

CardioVascular and Interventional Radiology, Jul 15, 2000

A 54-year-old man with persistent chest pain was hospitalized for hypertension and DeBakey type I... more A 54-year-old man with persistent chest pain was hospitalized for hypertension and DeBakey type IIIb aortic dissection. The false lumen of the dissection was almost completely thrombosed; however, a penetrating atherosclerotic ulcer (PAU) was observed 5 weeks later. At that time, we successfully embolized the PAU with a microcatheter and interlocking detachable coils (IDCs). The patient is well with no episodes of relapse in 20 months of follow-up. This case suggests the utility of the microcatheter and IDC system as an alternative to surgery.