Conrad Falkson - Academia.edu (original) (raw)
Papers by Conrad Falkson
American Journal of Clinical Oncology, Dec 1, 1988
Esthesioneuroblastoma is an uncommon tumor arising from the olfactory epithelium of the nasal vau... more Esthesioneuroblastoma is an uncommon tumor arising from the olfactory epithelium of the nasal vault. Differentiation from other tumors is often difficult, but techniques like immunocytochemistry and electron microscopy can help to distinguish a neuroblastoma from a malignant lymphoma with certainty. A patient is presented in whom difficulty was experienced in deciding on the diagnosis; the pathological data are presented to illustrate why confusion about the finite diagnosis can occur despite the use of these techniques. The initial diagnosis was a malignant lymphoma of the poorly differentiated lymphocytic type. The disease responded well to chemotherapy with cyclophosphamide, vincristine, procarbazine, and doxorubicin (COPA). When tumor recurred, rebiopsy of the small cell tumor was considered to be esthesioneuroblastoma, and the patient was treated with cyclophosphamide, vincristine, dacarbazine, and radiotherapy. The patient is now disease-free and has been without evidence of disease for more than 2.5 years; it is more than 5 years since the initial diagnosis of a small cell malignant neoplasm was made. This report illustrates the problems of diagnosis and treatment of this rare condition.
Canadian Journal of Cardiology, Oct 1, 2013
Mediastinum, Dec 1, 2022
Background: Thymomas are characterized by a low tumor mutation burden and a paucity of actionable... more Background: Thymomas are characterized by a low tumor mutation burden and a paucity of actionable mutations. Clinical behavior can vary from relatively indolent to very aggressive and impact survival. Platinum-based chemotherapy is the primary treatment modality for inoperable disease and is palliative in intent. Patients with advanced thymoma frequently experience disease recurrence after frontline therapy. Treatment options for relapsed thymoma are relatively limited. A case of recurrent thymoma harboring a breast cancer gene 2 (BRCA2) mutation was presented for multidisciplinary discussion at the International Thymic Malignancy Interest Group (ITMIG) Tumor Board meeting. Case Description: A 63-year-old female presented with Tumor Node Metastasis (TNM) stage I, World Health Organization (WHO) subtype B1 thymoma at diagnosis and underwent surgical resection. First recurrence occurred in the left costophrenic recess and was treated with preoperative external beam radiotherapy (EBRT), surgical excision, and post-operative chemotherapy. Histology was consistent with WHO subtype B2 thymoma and genomic analysis of the resected tumor detected a BRCA2 mutation. Second recurrence occurred in the mediastinum and bilateral pleurae. Mediastinal disease was treated with EBRT, and the pleural deposits were observed initially. However, upon further progression, the case was discussed at the ITMIG tumor board meeting to determine optimal second line therapy for this patient. Conclusions: A potential role of poly (ADP-ribose) polymerase (PARP) inhibitors versus cytotoxic chemotherapy for treatment of BRCA2-mutated recurrent thymoma merits discussion. However, due to the absence of data to support the functional and therapeutic significance of BRCA2 mutations in patients with thymoma, the potential for severe toxicity associated with PARP inhibitors, and availability of other safe and effective alternatives, other treatment options should be considered. PARP inhibitors can be considered for treatment of BRCA2-mutated thymomas as part of a clinical trial or when other treatment options have been exhausted.
Journal of Thoracic Oncology, 2018
Journal of Xiangya medicine, Jul 1, 2018
This review summarizes recent updates on the role and timing of radiotherapy (RT). Multidisciplin... more This review summarizes recent updates on the role and timing of radiotherapy (RT). Multidisciplinary case discussion and careful case selection before any treatment modality can avoid morbidity and mortality. Advances in RT technology include proton treatment, respiratory gating, immobilization, forward planning, intensity-modulated radiation (IMRT), volumetric-modulated arc therapy (VMAT), tomotherapy, image-guided radiation treatment (IGRT) and on-treatment cone-beam computerized axial tomography scan (CBCT). These allow decreased doses to organ at risk such as brachial plexus, ribs, spinal cord, contralateral esophagus (CE), lung, heart, and adjacent liver. We used mesothelioma and thymoma as an example to illustrate improvements in RT techniques in past decade.
PubMed, May 1, 1996
Objectives: To evaluate fludarabine in patients with chronic lymphocytic leukaemia (CLL) not resp... more Objectives: To evaluate fludarabine in patients with chronic lymphocytic leukaemia (CLL) not responding to standard treatment. Design setting: Fludarabine was administered for 5 consecutive days and repeated 4-weekly. Subjects: Seventeen patients at a single institution were treated. Outcome measures: Objective remission was seen in 11 patients. The median survival time was 356 days. Results and conclusions: Fludarabine is an effective treatment for patients with advanced CLL.
International Journal of Radiation Oncology Biology Physics, Nov 1, 2020
regressions. Criteria for statistical significance was p < 0.05. This study was approved by the I... more regressions. Criteria for statistical significance was p < 0.05. This study was approved by the IRB. Results: A total of 445 survey responses were collected. Two-hundred (45%) respondents agreed that online physician rating websites contribute to burnout, 200 (45%) respondents were neutral, and 45 (10%) respondents disagreed. Of all respondents, 313 were men, 130 were women, and 2 were other gender. Both men and women were more likely to agree than disagree that online reviews contribute to burnout. Forty-one percent of men agreed and 12% disagreed, whereas 55% of women agreed and 7% disagreed (p Z 0.03); these findings also indicate that men were more likely to be neutral than women. Of all respondents who agreed online reviews contribute to burnout, 84 (42.0%) were between the ages of 35 and 50 years, 60 (30.0%) were between the ages of 50 and 60 years, and 56 (28.0%) were above the age of 60 years. Of all respondents who disagreed that online reviews contribute to burnout, 14 (31.1%) were between the ages of 35 and 50 years, 11 (24.4%) were between the ages of 50 and 60 years, and 20 (44.4%) were above the age of 60 years. There was a linear trend in the relationship of ordinal burnout categories and age categories (p Z 0.033). The relationship between perceived burnout and age did not differ by gender (p Z 0.53), although there was some evidence that gender confounds the relationship of age with burnout. Conclusion: Younger physicians and women are more likely to perceive that online patient reviews contribute to burnout than older physicians and men. This suggests that online reviews may have an increasing effect on physician burnout in the future. Future research could investigate potential burnout secondary to online physician reviews and prevention strategies.
progress of individual medical and surgical teams throughout the implementation timeline (Figure ... more progress of individual medical and surgical teams throughout the implementation timeline (Figure 1). Our secondary outcome measure was the percentage of patients discharged within 2 hours of meeting their medical discharge goals. Results The percentage of patients whose discharge process included medical goals increased from 25% to 76% in 3 years. The progress of individual teams is displayed in Figure 2. For patients who followed the process, the percentage of patients discharged within 2 hours of meeting medical discharge goals increased from 42% to 85% (Figure 3); however, this overestimates success, as patients are only included in this measure if all parts of the process are followed. Conclusions We successfully spread discharge efficiency based upon medical goals to a majority of hospitalised acute care patients; however, we continue to identify improvement opportunities with process adherence.
International Journal of Radiation Oncology Biology Physics, Sep 1, 2019
We know that a major pathologic tumor response following neoadjuvant therapy is associated with a... more We know that a major pathologic tumor response following neoadjuvant therapy is associated with an increased overall survival. In recent years standard of care chemotherapy regimen in neoadjuvant management of esophageal cancer has changed from cisplatin/5-FU (CIF) to carboplatin/paclitaxel (CAP). We compared treatment responses (using College of American Pathologist's protocol) among patients who received neoadjuvant therapy using either CIF or CAP with concomitant radiation therapy (RT). Materials/Methods: Retrospective chart review of all patients who received neoadjuvant therapy followed by surgery for esophageal cancer diagnosed between 2008-2018 at a single academic center was completed. Descriptive statistics and bivariate analyses (Chi-square, t-tests) were utilized to analyze the data. Results: Of the 80 eligible patients, 84% were male with a median age was 62.5 years, most (85%) had lower esophageal lesions and the most common histology was adenocarcinoma (86.3%), followed by squamous cell carcinoma (12.5%). Most patients received 50Gy radiation dose (92.5%) with fewer receiving 41.4Gy (7.5%). All recent patients (57.5%) received CAP in comparison with historical controls (42.5%), who received CIF. Median time between completion of neoadjuvant therapy and surgery was 65.5 days. Following neoadjuvant therapy, 63.2% had a tumor regression grade (TRG) of 0 or 1. There was no significant difference in tumor regression grade of (0 and 1) or (2 and 3) between groups receiving CAP or CIF (pZ0.686), or in tumor down staging (ypT) (pZ1.0). There was no change in TRG after excluding patients receiving 41.4 Gy. Most resection specimens (74%) were negative for lymph node metastasis (ypN0). Pathologic ypT stages (AJCC 8e.) were 0 (37.5%), 1A (3.8%), 1B (8.8%), 2 (12.5%) and 3(37.5%). Five patients (6.3%) had positive resection margins; of these, 3 died of metastatic disease and 2 are well with no evidence of local recurrence or metastatic disease. Conclusion: Most esophageal cancer patients had a major pathologic response (TRG score 0 or 1) to neoadjuvant chemo-radiation therapy and were ypN0. There was no significant difference in tumor regression grade or tumor down-staging between the two chemotherapy regimens.
Brachytherapy, Jul 1, 2023
Current Oncology, Aug 1, 2016
Current Oncology, Feb 1, 2017
Objectives For this guideline, we investigated the effectiveness of radiotherapy with curative in... more Objectives For this guideline, we investigated the effectiveness of radiotherapy with curative intent in medically inoperable patients with early-stage non-small-cell lung cancer (nsclc). Methods The guideline was developed by Cancer Care Ontario's Program in Evidence-Based Care and by the Lung Cancer Disease Site Group through a systematic review of mainly retrospective studies, expert consensus, and formal internal and external reviews. Recommendations ■ Stereotactic body radiation therapy (sbrt) with curative intent is an option that should be considered for patients with early-stage, node-negative, medically inoperable nsclc. Qualifying Statements ■ Because of the high dose per fraction, the planning process and treatment delivery for sbrt require the use of advanced technology to maintain an appropriate level of safety. Consistent patient positioning and 4-dimensional analysis of tumour and critical structure motion during simulation and treatment delivery are essential. ■ Preliminary results for proton-beam therapy have been promising, but the technique requires further clinical study. ■ Recommended fractionation schemes for sbrt should result in a biologically effective dose of 100 or greater by the linear quadric model, choosing an α/β value of 10 [bed 10(LQ) ≥ 100]. Qualifying Statements ■ Because of the increased risk of treatment-related adverse events associated with centrally located tumours, consideration of tumour size and proximity to critical central structures is required when determining the dose and fractionation. ■ Examples of dose-fractionation schemes used in the included studies have been provided. ■ Based on the current evidence and the opinion of the authors, radiation doses at bed 10(LQ) greater than 146 might significantly increase toxicity and should be avoided. ■ Determination of the radiation bed by the linear quadratic model has limitations for the extreme hypofractionated schemes used in sbrt.
Investigational New Drugs, Nov 1, 1992
Forty three patients with histologically confirmed malignant mesothelioma were entered onto an Ea... more Forty three patients with histologically confirmed malignant mesothelioma were entered onto an Eastern Cooperative Oncology Group phase II study of ifosfamide given with mesna. Eligibility criteria included adequate performance status, hemogram and renal functions. Ifosfamide was given at 1.5 g/m2 in 200 ml of normal saline over 30 minutes by intravenous infusion on days 1 to 5 of each 21 day cycle. Mesna was given at 300 mg/m2 on each day of ifosfamide at 0, 4 and 8 hours. Two patients were cancelled and one patient was ineligible. The most common toxicity was haematologic. More than 50% of the patients had at least one episode of severe or life threatening toxicity and 2 patients had lethal toxicity (1 renal and 1 pulmonary oedema attributed to treatment), and an additional 4 patients died while on study (2 of cardiac and 2 of cerebral vascular disease not considered directly related to treatment). Of the 40 eligible patients one was unevaluable for response, and one patient had a partial response lasting 6.3 months. Twenty four patients had a no change status with a median duration of 5 months. The median time to treatment failure for all eligible patients was 2.5 months. The median overall survival time (from registration) for all eligible patients was 6.9 months. In multi variable models, factors that predicted for a statistically significant poorer survival were age > or = 62, stage > or = 3, performance status poorer than 0 to 1 and prior surgery (i.e.: more than biopsy).(ABSTRACT TRUNCATED AT 250 WORDS)
International Journal of Radiation Oncology Biology Physics, Oct 1, 2016
The recommended treatment for early-stage breast cancer is breast-conserving surgery followed by ... more The recommended treatment for early-stage breast cancer is breast-conserving surgery followed by radiation. Whole-breast irradiation is the current standard of care. An alternative is accelerated partial breast irradiation using multicatheter interstitial brachytherapy, which may be used to deliver radiation therapy in 1 week or less. To achieve ideal dosimetry over the tumor bed, the catheters must be placed parallel with equal spacing in the highly deformable breast tissue, currently a technical challenge. Our proposal uses real-time electromagnetic (EMT) navigation to accurately insert catheters. Materials/Methods: A tissue-locking needle and ultrasound (US) probe is equipped with EMT capability. The needle is inserted and locked in the tumor bed under US guidance, which provides a locally rigid reference. The desired volume is contoured in US, resulting in a tracked model of the tumor bed in a virtual view. An EMT-enabled needle guide is pointed at the target and a catheter needle is inserted through the guide into the tissue. Additional parallel catheters are planned on the virtual view based on the first insertion and implanted in the target. The guidance software is built on the 3D Slicer (www.slicer.org) open source platform. Anthropomorphic plastic phantoms were made, each having a simulated tumor bed that can be visualized in both US and CT. Our demonstration contained 2 rows of 5 catheter needles per row, for a total of 10 catheters, which were inserted in the 2 phantoms. The purpose was to position each catheter 1.0 cm apart. The first phantom had catheter needles inserted under sole US guidance to the target and the second under combined EMT-US guidance. Both insertions were performed by the same operator. The position of the catheters relative to the tumor bed was measured in CT. Results: Under sole US guidance, 7 out of 10 catheters passed through the tumor bed. The catheter spacing was inconsistent and the desired goal of 2 rows of 5 equally spaced catheters was not precisely achieved, with a mean spacing of 1.0 cm with 0.7-1.9 cm range. Using combined EMT-US guidance, 9 out of 10 catheters passed through the tumor bed, resulting in 2 rows of 5 catheters with more consistent spacing and a mean spacing of 1.0 cm with 0.8-1.2 cm range. Conclusion: This phantom experiment suggests that combined EMT-US guidance can be a potential tool to help achieve consistent catheter spacing over a tumor bed. These results are preliminary, and a trial of the method is now being conducted to validate our results. Additional research is also being performed to translate the proposed navigation technique to patient trials.
International Journal of Radiation Oncology Biology Physics, Sep 1, 2019
Conclusion: An investigation was performed to estimate the geometric distortion in clinical MR se... more Conclusion: An investigation was performed to estimate the geometric distortion in clinical MR sequences for an MR-Linac system. The magnitude of measured geometric distortion varied depending on the clinical MR sequence used for image acquisition. Any MR-Linac radiation treatment related decision-making should take this source of uncertainty into consideration.
International Journal of Radiation Oncology Biology Physics, Oct 1, 2016
combination (ACRT), neoadjuvant chemoradiotherapy combination (NCRT), and mixed (M) CRT (NCT + AR... more combination (ACRT), neoadjuvant chemoradiotherapy combination (NCRT), and mixed (M) CRT (NCT + ART or NRT + ACT). Kaplan-Meier method estimated overall survival (OS). Proportional hazards model estimated OS hazard ratios for prognostic factors including age, comorbidity, gender, race, margin, histology, RT technique, RT dose, and CT type. Results: With a median follow-up of 34 months, the cohort included 2,298 male and 1,774 females with a median age of 61 years (range: 18-90). RT and CT were delivered in 2,567 and 1,228 patients reducing mortality hazards ratio (HR) 0.61 (95% confidence intervals (CIs) 0.54-0.68); and 0.65 (CI: 0.58-0.73), respectively, compared with surgery alone. The 5year OS was 36%, 58%, 59%, 49%, 56%, 55%, 52%, and 51% in SA, ACRT, NCRT, ACT, NCT, M, ART, and NRT, respectively. Timing of treatment intervention, either adjuvant or neoadjuvant, did not result in significant survival advantage. ACRT, NCRT, and M trended towards an improvement in survival compared to other approaches. There was a mortality HR reduction of 0.46 (CI: 0.39-0.55), 0.66 (CI: 0.53-0.84), and 0.60 (CI: 0.53-0.68) in combined modalities, when compared to CT alone and RT alone, respectively. On multivariate analysis, age older than 50 years, positive margins, higher Charlson comorbidity score, and surgery alone were significant predictors of poor outcome. Conclusion: Our analysis hints that combined modality approach leads to better survival in patients with large, high-grade sarcoma. Further studies are warranted to establish this paradigm as the standard of care.
International Journal of Radiation Oncology*Biology*Physics
International Journal of Radiation Oncology Biology Physics, 2020
Purpose/Objective(s): Management options are limited for a primary or secondary malignant airway ... more Purpose/Objective(s): Management options are limited for a primary or secondary malignant airway disease. This study evaluates symptomatic response, toxicities and local control of endobronchial malignancy treated with HDR. Materials/Methods: A retrospective chart review was conducted and data collected on all patients treated between 2010 and 2019 who received brachytherapy for endobronchial obstructive airway disease at one center. AJCC 8 th edition was used for staging. All patients were treated using an iridium-192 isotope source to deliver a dose of 14 Gy in 2 fractions a week apart. Treatment length of the endobronchial disease was defined by imaging and endoscopic findings. Computed-tomography was used to define the volume. Results: A total of 58 patients were identified; 34 (58.6%) were male and 24 (41.4%) female. Most (49, 84%) had a primary lung cancer and 9 (15.5%) had metastatic endobronchial disease from a primary elsewhere. Most lung cancer patients had stage III and IV (40, 69%). Eight (13.8%) were treated while admitted in the ICU. About half (52%) had prior external beam radiotherapy and 14 (24.1%) were treated with a curative intent. Most (47, 81%) reported a symptomatic improvement in dyspnea, cough, or hemoptysis. An improvement in dyspnea was seen in 72% of presenting with this symptom. The MRC dyspnea scale score improved by a mean of 1.13 (P<0.001, Wilcoxon paired samples test). Most (22, 88%) had an improvement in hemoptysis and 18 out of 37 (48.6%) had an improvement in cough. Grade I to III adverse events including dyspnea, small volume hemoptysis, or cough were noted in 25 (43.1%). Grade 4-5 hemoptysis occurred in 7(12%) at the median time of 2.5 months. Grade 4-5 dyspnea was seen in 3 patients. Median progression free survival was 6.5 months and median survival was 10 months. Median survival for patients treated with curative intent was 43 months. Conclusion: We report a significant symptomatic benefit after brachytherapy among patients with endobronchial malignant disease including among patients admitted to ICU for their dyspnea, hemoptysis and cough. Most had previous treatment. Toxicities such as significant hemoptysis were consistent with the prior reports. Limitations include retrospective data collection. We suggest an increase in awareness of endobronchial brachytherapy and provision of opportunities for trainees to learn this modality.
Journal of Thoracic Oncology, 2009
American Journal of Clinical Oncology, Dec 1, 1988
Esthesioneuroblastoma is an uncommon tumor arising from the olfactory epithelium of the nasal vau... more Esthesioneuroblastoma is an uncommon tumor arising from the olfactory epithelium of the nasal vault. Differentiation from other tumors is often difficult, but techniques like immunocytochemistry and electron microscopy can help to distinguish a neuroblastoma from a malignant lymphoma with certainty. A patient is presented in whom difficulty was experienced in deciding on the diagnosis; the pathological data are presented to illustrate why confusion about the finite diagnosis can occur despite the use of these techniques. The initial diagnosis was a malignant lymphoma of the poorly differentiated lymphocytic type. The disease responded well to chemotherapy with cyclophosphamide, vincristine, procarbazine, and doxorubicin (COPA). When tumor recurred, rebiopsy of the small cell tumor was considered to be esthesioneuroblastoma, and the patient was treated with cyclophosphamide, vincristine, dacarbazine, and radiotherapy. The patient is now disease-free and has been without evidence of disease for more than 2.5 years; it is more than 5 years since the initial diagnosis of a small cell malignant neoplasm was made. This report illustrates the problems of diagnosis and treatment of this rare condition.
Canadian Journal of Cardiology, Oct 1, 2013
Mediastinum, Dec 1, 2022
Background: Thymomas are characterized by a low tumor mutation burden and a paucity of actionable... more Background: Thymomas are characterized by a low tumor mutation burden and a paucity of actionable mutations. Clinical behavior can vary from relatively indolent to very aggressive and impact survival. Platinum-based chemotherapy is the primary treatment modality for inoperable disease and is palliative in intent. Patients with advanced thymoma frequently experience disease recurrence after frontline therapy. Treatment options for relapsed thymoma are relatively limited. A case of recurrent thymoma harboring a breast cancer gene 2 (BRCA2) mutation was presented for multidisciplinary discussion at the International Thymic Malignancy Interest Group (ITMIG) Tumor Board meeting. Case Description: A 63-year-old female presented with Tumor Node Metastasis (TNM) stage I, World Health Organization (WHO) subtype B1 thymoma at diagnosis and underwent surgical resection. First recurrence occurred in the left costophrenic recess and was treated with preoperative external beam radiotherapy (EBRT), surgical excision, and post-operative chemotherapy. Histology was consistent with WHO subtype B2 thymoma and genomic analysis of the resected tumor detected a BRCA2 mutation. Second recurrence occurred in the mediastinum and bilateral pleurae. Mediastinal disease was treated with EBRT, and the pleural deposits were observed initially. However, upon further progression, the case was discussed at the ITMIG tumor board meeting to determine optimal second line therapy for this patient. Conclusions: A potential role of poly (ADP-ribose) polymerase (PARP) inhibitors versus cytotoxic chemotherapy for treatment of BRCA2-mutated recurrent thymoma merits discussion. However, due to the absence of data to support the functional and therapeutic significance of BRCA2 mutations in patients with thymoma, the potential for severe toxicity associated with PARP inhibitors, and availability of other safe and effective alternatives, other treatment options should be considered. PARP inhibitors can be considered for treatment of BRCA2-mutated thymomas as part of a clinical trial or when other treatment options have been exhausted.
Journal of Thoracic Oncology, 2018
Journal of Xiangya medicine, Jul 1, 2018
This review summarizes recent updates on the role and timing of radiotherapy (RT). Multidisciplin... more This review summarizes recent updates on the role and timing of radiotherapy (RT). Multidisciplinary case discussion and careful case selection before any treatment modality can avoid morbidity and mortality. Advances in RT technology include proton treatment, respiratory gating, immobilization, forward planning, intensity-modulated radiation (IMRT), volumetric-modulated arc therapy (VMAT), tomotherapy, image-guided radiation treatment (IGRT) and on-treatment cone-beam computerized axial tomography scan (CBCT). These allow decreased doses to organ at risk such as brachial plexus, ribs, spinal cord, contralateral esophagus (CE), lung, heart, and adjacent liver. We used mesothelioma and thymoma as an example to illustrate improvements in RT techniques in past decade.
PubMed, May 1, 1996
Objectives: To evaluate fludarabine in patients with chronic lymphocytic leukaemia (CLL) not resp... more Objectives: To evaluate fludarabine in patients with chronic lymphocytic leukaemia (CLL) not responding to standard treatment. Design setting: Fludarabine was administered for 5 consecutive days and repeated 4-weekly. Subjects: Seventeen patients at a single institution were treated. Outcome measures: Objective remission was seen in 11 patients. The median survival time was 356 days. Results and conclusions: Fludarabine is an effective treatment for patients with advanced CLL.
International Journal of Radiation Oncology Biology Physics, Nov 1, 2020
regressions. Criteria for statistical significance was p < 0.05. This study was approved by the I... more regressions. Criteria for statistical significance was p < 0.05. This study was approved by the IRB. Results: A total of 445 survey responses were collected. Two-hundred (45%) respondents agreed that online physician rating websites contribute to burnout, 200 (45%) respondents were neutral, and 45 (10%) respondents disagreed. Of all respondents, 313 were men, 130 were women, and 2 were other gender. Both men and women were more likely to agree than disagree that online reviews contribute to burnout. Forty-one percent of men agreed and 12% disagreed, whereas 55% of women agreed and 7% disagreed (p Z 0.03); these findings also indicate that men were more likely to be neutral than women. Of all respondents who agreed online reviews contribute to burnout, 84 (42.0%) were between the ages of 35 and 50 years, 60 (30.0%) were between the ages of 50 and 60 years, and 56 (28.0%) were above the age of 60 years. Of all respondents who disagreed that online reviews contribute to burnout, 14 (31.1%) were between the ages of 35 and 50 years, 11 (24.4%) were between the ages of 50 and 60 years, and 20 (44.4%) were above the age of 60 years. There was a linear trend in the relationship of ordinal burnout categories and age categories (p Z 0.033). The relationship between perceived burnout and age did not differ by gender (p Z 0.53), although there was some evidence that gender confounds the relationship of age with burnout. Conclusion: Younger physicians and women are more likely to perceive that online patient reviews contribute to burnout than older physicians and men. This suggests that online reviews may have an increasing effect on physician burnout in the future. Future research could investigate potential burnout secondary to online physician reviews and prevention strategies.
progress of individual medical and surgical teams throughout the implementation timeline (Figure ... more progress of individual medical and surgical teams throughout the implementation timeline (Figure 1). Our secondary outcome measure was the percentage of patients discharged within 2 hours of meeting their medical discharge goals. Results The percentage of patients whose discharge process included medical goals increased from 25% to 76% in 3 years. The progress of individual teams is displayed in Figure 2. For patients who followed the process, the percentage of patients discharged within 2 hours of meeting medical discharge goals increased from 42% to 85% (Figure 3); however, this overestimates success, as patients are only included in this measure if all parts of the process are followed. Conclusions We successfully spread discharge efficiency based upon medical goals to a majority of hospitalised acute care patients; however, we continue to identify improvement opportunities with process adherence.
International Journal of Radiation Oncology Biology Physics, Sep 1, 2019
We know that a major pathologic tumor response following neoadjuvant therapy is associated with a... more We know that a major pathologic tumor response following neoadjuvant therapy is associated with an increased overall survival. In recent years standard of care chemotherapy regimen in neoadjuvant management of esophageal cancer has changed from cisplatin/5-FU (CIF) to carboplatin/paclitaxel (CAP). We compared treatment responses (using College of American Pathologist's protocol) among patients who received neoadjuvant therapy using either CIF or CAP with concomitant radiation therapy (RT). Materials/Methods: Retrospective chart review of all patients who received neoadjuvant therapy followed by surgery for esophageal cancer diagnosed between 2008-2018 at a single academic center was completed. Descriptive statistics and bivariate analyses (Chi-square, t-tests) were utilized to analyze the data. Results: Of the 80 eligible patients, 84% were male with a median age was 62.5 years, most (85%) had lower esophageal lesions and the most common histology was adenocarcinoma (86.3%), followed by squamous cell carcinoma (12.5%). Most patients received 50Gy radiation dose (92.5%) with fewer receiving 41.4Gy (7.5%). All recent patients (57.5%) received CAP in comparison with historical controls (42.5%), who received CIF. Median time between completion of neoadjuvant therapy and surgery was 65.5 days. Following neoadjuvant therapy, 63.2% had a tumor regression grade (TRG) of 0 or 1. There was no significant difference in tumor regression grade of (0 and 1) or (2 and 3) between groups receiving CAP or CIF (pZ0.686), or in tumor down staging (ypT) (pZ1.0). There was no change in TRG after excluding patients receiving 41.4 Gy. Most resection specimens (74%) were negative for lymph node metastasis (ypN0). Pathologic ypT stages (AJCC 8e.) were 0 (37.5%), 1A (3.8%), 1B (8.8%), 2 (12.5%) and 3(37.5%). Five patients (6.3%) had positive resection margins; of these, 3 died of metastatic disease and 2 are well with no evidence of local recurrence or metastatic disease. Conclusion: Most esophageal cancer patients had a major pathologic response (TRG score 0 or 1) to neoadjuvant chemo-radiation therapy and were ypN0. There was no significant difference in tumor regression grade or tumor down-staging between the two chemotherapy regimens.
Brachytherapy, Jul 1, 2023
Current Oncology, Aug 1, 2016
Current Oncology, Feb 1, 2017
Objectives For this guideline, we investigated the effectiveness of radiotherapy with curative in... more Objectives For this guideline, we investigated the effectiveness of radiotherapy with curative intent in medically inoperable patients with early-stage non-small-cell lung cancer (nsclc). Methods The guideline was developed by Cancer Care Ontario's Program in Evidence-Based Care and by the Lung Cancer Disease Site Group through a systematic review of mainly retrospective studies, expert consensus, and formal internal and external reviews. Recommendations ■ Stereotactic body radiation therapy (sbrt) with curative intent is an option that should be considered for patients with early-stage, node-negative, medically inoperable nsclc. Qualifying Statements ■ Because of the high dose per fraction, the planning process and treatment delivery for sbrt require the use of advanced technology to maintain an appropriate level of safety. Consistent patient positioning and 4-dimensional analysis of tumour and critical structure motion during simulation and treatment delivery are essential. ■ Preliminary results for proton-beam therapy have been promising, but the technique requires further clinical study. ■ Recommended fractionation schemes for sbrt should result in a biologically effective dose of 100 or greater by the linear quadric model, choosing an α/β value of 10 [bed 10(LQ) ≥ 100]. Qualifying Statements ■ Because of the increased risk of treatment-related adverse events associated with centrally located tumours, consideration of tumour size and proximity to critical central structures is required when determining the dose and fractionation. ■ Examples of dose-fractionation schemes used in the included studies have been provided. ■ Based on the current evidence and the opinion of the authors, radiation doses at bed 10(LQ) greater than 146 might significantly increase toxicity and should be avoided. ■ Determination of the radiation bed by the linear quadratic model has limitations for the extreme hypofractionated schemes used in sbrt.
Investigational New Drugs, Nov 1, 1992
Forty three patients with histologically confirmed malignant mesothelioma were entered onto an Ea... more Forty three patients with histologically confirmed malignant mesothelioma were entered onto an Eastern Cooperative Oncology Group phase II study of ifosfamide given with mesna. Eligibility criteria included adequate performance status, hemogram and renal functions. Ifosfamide was given at 1.5 g/m2 in 200 ml of normal saline over 30 minutes by intravenous infusion on days 1 to 5 of each 21 day cycle. Mesna was given at 300 mg/m2 on each day of ifosfamide at 0, 4 and 8 hours. Two patients were cancelled and one patient was ineligible. The most common toxicity was haematologic. More than 50% of the patients had at least one episode of severe or life threatening toxicity and 2 patients had lethal toxicity (1 renal and 1 pulmonary oedema attributed to treatment), and an additional 4 patients died while on study (2 of cardiac and 2 of cerebral vascular disease not considered directly related to treatment). Of the 40 eligible patients one was unevaluable for response, and one patient had a partial response lasting 6.3 months. Twenty four patients had a no change status with a median duration of 5 months. The median time to treatment failure for all eligible patients was 2.5 months. The median overall survival time (from registration) for all eligible patients was 6.9 months. In multi variable models, factors that predicted for a statistically significant poorer survival were age > or = 62, stage > or = 3, performance status poorer than 0 to 1 and prior surgery (i.e.: more than biopsy).(ABSTRACT TRUNCATED AT 250 WORDS)
International Journal of Radiation Oncology Biology Physics, Oct 1, 2016
The recommended treatment for early-stage breast cancer is breast-conserving surgery followed by ... more The recommended treatment for early-stage breast cancer is breast-conserving surgery followed by radiation. Whole-breast irradiation is the current standard of care. An alternative is accelerated partial breast irradiation using multicatheter interstitial brachytherapy, which may be used to deliver radiation therapy in 1 week or less. To achieve ideal dosimetry over the tumor bed, the catheters must be placed parallel with equal spacing in the highly deformable breast tissue, currently a technical challenge. Our proposal uses real-time electromagnetic (EMT) navigation to accurately insert catheters. Materials/Methods: A tissue-locking needle and ultrasound (US) probe is equipped with EMT capability. The needle is inserted and locked in the tumor bed under US guidance, which provides a locally rigid reference. The desired volume is contoured in US, resulting in a tracked model of the tumor bed in a virtual view. An EMT-enabled needle guide is pointed at the target and a catheter needle is inserted through the guide into the tissue. Additional parallel catheters are planned on the virtual view based on the first insertion and implanted in the target. The guidance software is built on the 3D Slicer (www.slicer.org) open source platform. Anthropomorphic plastic phantoms were made, each having a simulated tumor bed that can be visualized in both US and CT. Our demonstration contained 2 rows of 5 catheter needles per row, for a total of 10 catheters, which were inserted in the 2 phantoms. The purpose was to position each catheter 1.0 cm apart. The first phantom had catheter needles inserted under sole US guidance to the target and the second under combined EMT-US guidance. Both insertions were performed by the same operator. The position of the catheters relative to the tumor bed was measured in CT. Results: Under sole US guidance, 7 out of 10 catheters passed through the tumor bed. The catheter spacing was inconsistent and the desired goal of 2 rows of 5 equally spaced catheters was not precisely achieved, with a mean spacing of 1.0 cm with 0.7-1.9 cm range. Using combined EMT-US guidance, 9 out of 10 catheters passed through the tumor bed, resulting in 2 rows of 5 catheters with more consistent spacing and a mean spacing of 1.0 cm with 0.8-1.2 cm range. Conclusion: This phantom experiment suggests that combined EMT-US guidance can be a potential tool to help achieve consistent catheter spacing over a tumor bed. These results are preliminary, and a trial of the method is now being conducted to validate our results. Additional research is also being performed to translate the proposed navigation technique to patient trials.
International Journal of Radiation Oncology Biology Physics, Sep 1, 2019
Conclusion: An investigation was performed to estimate the geometric distortion in clinical MR se... more Conclusion: An investigation was performed to estimate the geometric distortion in clinical MR sequences for an MR-Linac system. The magnitude of measured geometric distortion varied depending on the clinical MR sequence used for image acquisition. Any MR-Linac radiation treatment related decision-making should take this source of uncertainty into consideration.
International Journal of Radiation Oncology Biology Physics, Oct 1, 2016
combination (ACRT), neoadjuvant chemoradiotherapy combination (NCRT), and mixed (M) CRT (NCT + AR... more combination (ACRT), neoadjuvant chemoradiotherapy combination (NCRT), and mixed (M) CRT (NCT + ART or NRT + ACT). Kaplan-Meier method estimated overall survival (OS). Proportional hazards model estimated OS hazard ratios for prognostic factors including age, comorbidity, gender, race, margin, histology, RT technique, RT dose, and CT type. Results: With a median follow-up of 34 months, the cohort included 2,298 male and 1,774 females with a median age of 61 years (range: 18-90). RT and CT were delivered in 2,567 and 1,228 patients reducing mortality hazards ratio (HR) 0.61 (95% confidence intervals (CIs) 0.54-0.68); and 0.65 (CI: 0.58-0.73), respectively, compared with surgery alone. The 5year OS was 36%, 58%, 59%, 49%, 56%, 55%, 52%, and 51% in SA, ACRT, NCRT, ACT, NCT, M, ART, and NRT, respectively. Timing of treatment intervention, either adjuvant or neoadjuvant, did not result in significant survival advantage. ACRT, NCRT, and M trended towards an improvement in survival compared to other approaches. There was a mortality HR reduction of 0.46 (CI: 0.39-0.55), 0.66 (CI: 0.53-0.84), and 0.60 (CI: 0.53-0.68) in combined modalities, when compared to CT alone and RT alone, respectively. On multivariate analysis, age older than 50 years, positive margins, higher Charlson comorbidity score, and surgery alone were significant predictors of poor outcome. Conclusion: Our analysis hints that combined modality approach leads to better survival in patients with large, high-grade sarcoma. Further studies are warranted to establish this paradigm as the standard of care.
International Journal of Radiation Oncology*Biology*Physics
International Journal of Radiation Oncology Biology Physics, 2020
Purpose/Objective(s): Management options are limited for a primary or secondary malignant airway ... more Purpose/Objective(s): Management options are limited for a primary or secondary malignant airway disease. This study evaluates symptomatic response, toxicities and local control of endobronchial malignancy treated with HDR. Materials/Methods: A retrospective chart review was conducted and data collected on all patients treated between 2010 and 2019 who received brachytherapy for endobronchial obstructive airway disease at one center. AJCC 8 th edition was used for staging. All patients were treated using an iridium-192 isotope source to deliver a dose of 14 Gy in 2 fractions a week apart. Treatment length of the endobronchial disease was defined by imaging and endoscopic findings. Computed-tomography was used to define the volume. Results: A total of 58 patients were identified; 34 (58.6%) were male and 24 (41.4%) female. Most (49, 84%) had a primary lung cancer and 9 (15.5%) had metastatic endobronchial disease from a primary elsewhere. Most lung cancer patients had stage III and IV (40, 69%). Eight (13.8%) were treated while admitted in the ICU. About half (52%) had prior external beam radiotherapy and 14 (24.1%) were treated with a curative intent. Most (47, 81%) reported a symptomatic improvement in dyspnea, cough, or hemoptysis. An improvement in dyspnea was seen in 72% of presenting with this symptom. The MRC dyspnea scale score improved by a mean of 1.13 (P<0.001, Wilcoxon paired samples test). Most (22, 88%) had an improvement in hemoptysis and 18 out of 37 (48.6%) had an improvement in cough. Grade I to III adverse events including dyspnea, small volume hemoptysis, or cough were noted in 25 (43.1%). Grade 4-5 hemoptysis occurred in 7(12%) at the median time of 2.5 months. Grade 4-5 dyspnea was seen in 3 patients. Median progression free survival was 6.5 months and median survival was 10 months. Median survival for patients treated with curative intent was 43 months. Conclusion: We report a significant symptomatic benefit after brachytherapy among patients with endobronchial malignant disease including among patients admitted to ICU for their dyspnea, hemoptysis and cough. Most had previous treatment. Toxicities such as significant hemoptysis were consistent with the prior reports. Limitations include retrospective data collection. We suggest an increase in awareness of endobronchial brachytherapy and provision of opportunities for trainees to learn this modality.
Journal of Thoracic Oncology, 2009