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Featured researches published by Charles Cho.


Journal of Clinical Oncology | 2013

Sequential Phase I and II Trials of Stereotactic Body Radiotherapy for Locally Advanced Hepatocellular Carcinoma

Alexis Bujold; Christine Massey; John Kim; James D. Brierley; Charles Cho; Rebecca Wong; Rob Dinniwell; Zahra Kassam; Jolie Ringash; Bernard Cummings; Jenna Sykes; Morris Sherman; Jennifer J. Knox; Laura A. Dawson

PURPOSE To describe outcomes of prospective trials of stereotactic body radiotherapy (SBRT) for hepatocellular carcinoma (HCC). PATIENTS AND METHODS Two trials of SBRT for patients with active HCC unsuitable for standard locoregional therapies were conducted from 2004 to 2010. All patients had Child-Turcotte-Pugh class A disease, with at least 700 mL of non-HCC liver. The SBRT dose range was 24 to 54 Gy in six fractions. Primary end points were toxicity and local control at 1 year (LC1y), defined as no progressive disease (PD) of irradiated HCC by RECIST (Response Evaluation Criteria in Solid Tumors). RESULTS A total of 102 patients were evaluable (Trial 1, 2004 to 2007: n = 50; Trial 2, 2007 to 2010: n = 52). Underlying liver disease was hepatitis B in 38% of patients, hepatitis C in 38%, alcohol related in 25%, other in 14%, and none in 7%. Fifty-two percent received prior therapies (no prior sorafenib). TNM stage was III in 66%, and 61% had multiple lesions. Median gross tumor volume was 117.0 mL (range, 1.3 to 1,913.4 mL). Tumor vascular thrombosis (TVT) was present in 55%, and extrahepatic disease was present in 12%. LC1y was 87% (95% CI, 78% to 93%). SBRT dose (hazard ratio [HR] = 0.96; P = .02) and being in Trial 2 (HR = 0.38; P = .03) were associated with LC1y on univariate analysis. Toxicity ≥ grade 3 was seen in 30% of patients. In seven patients (two with TVT PD), death was possibly related to treatment (1.1 to 7.7 months after SBRT). Median overall survival was 17.0 months (95% CI, 10.4 to 21.3 months), for which only TVT (HR = 2.47; P = .01) and being in Trial 2 (HR = 0.49; P = .01) were significant on multivariate analysis. CONCLUSION These results provide strong rationale for studying SBRT for HCC in a randomized trial.


International Journal of Radiation Oncology Biology Physics | 2014

Prospective Evaluation of Acute Toxicity and Quality of Life After IMRT and Concurrent Chemotherapy for Anal Canal and Perianal Cancer

K. Han; Bernard Cummings; Patricia Lindsay; Julia Skliarenko; Timothy J. Craig; Lisa W. Le; James D. Brierley; Rebecca Wong; R. Dinniwell; A. Bayley; Laura A. Dawson; Jolie Ringash; Monika K. Krzyzanowska; Malcolm J. Moore; Eric X. Chen; Alexandra M. Easson; Zahra Kassam; Charles Cho; John Kim

PURPOSE A prospective cohort study was conducted to evaluate toxicity, quality of life (QOL), and clinical outcomes in patients treated with intensity modulated radiation therapy (IMRT) and concurrent chemotherapy for anal and perianal cancer. METHODS AND MATERIALS From June 2008 to November 2010, patients with anal or perianal cancer treated with IMRT were eligible. Radiation dose was 27 Gy in 15 fractions to 36 Gy in 20 fractions for elective targets and 45 Gy in 25 fractions to 63 Gy in 35 fractions for gross targets using standardized, institutional guidelines, with no planned treatment breaks. The chemotherapy regimen was 5-fluorouracil and mitomycin C. Toxicity was graded with the National Cancer Institute Common Terminology Criteria for Adverse Events, version 3. QOL was assessed with the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 and CR29 questionnaires. Correlations between dosimetric parameters and both physician-graded toxicities and patient-reported outcomes were evaluated by polyserial correlation. RESULTS Fifty-eight patients were enrolled. The median follow-up time was 34 months; the median age was 56 years; 52% of patients were female; and 19% were human immunodeficiency virus-positive. Stage I, II, III, and IV disease was found in 9%, 57%, 26%, and 9% of patients, respectively. Twenty-six patients (45%) required a treatment break because of acute toxicity, mainly dermatitis (23/26). Acute grade 3 + toxicities included skin 46%, hematologic 38%, gastrointestinal 9%, and genitourinary 0. The 2-year overall survival (OS), disease-free survival (DFS), colostomy-free survival (CFS), and cumulative locoregional failure (LRF) rates were 90%, 77%, 84%, and 16%, respectively. The global QOL/health status, skin, defecation, and pain scores were significantly worse at the end of treatment than at baseline, but they returned to baseline 3 months after treatment. Social functioning and appetite scores were significantly better at 12 months than at baseline. Multiple dose-volume parameters correlated moderately with diarrhea, skin, and hematologic toxicity scores. CONCLUSION IMRT reduces acute grade 3 + hematologic and gastrointestinal toxicities compared with reports from non-IMRT series, without compromising locoregional control. The reported QOL scores most relevant to acute toxicities returned to baseline by 3 months after treatment.


International Journal of Radiation Oncology Biology Physics | 2016

Phase 1 Trial of Sorafenib and Stereotactic Body Radiation Therapy for Hepatocellular Carcinoma

A. Brade; Sylvia Ng; James D. Brierley; John Kim; R. Dinniwell; Jolie Ringash; Rebecca Wong; Charles Cho; Jennifer J. Knox; Laura A. Dawson

PURPOSE To determine the maximally tolerated dose of sorafenib delivered before, during, and after stereotactic body radiation therapy (SBRT) in hepatocellular carinoma (HCC). METHODS AND MATERIALS Eligible patients had locally advanced Child-Pugh class A HCC, showed Eastern Cooperative Oncology Group performance status 0-1, and were ineligible for standard local-regional therapies. Sorafenib was dose escalated in 2 strata: (1) low effective irradiated liver volume (veff) < 30% and (2) high veff 30%to 60%. Sorafenib (400 mg daily = dose level 1) was administered for 12 weeks, with 6 fractions SBRT delivered weeks 2 and 3, and escalation to full dose (400 mg twice daily) after 12 weeks as tolerated. Standard 3 + 3 cohorts with dose escalation of sorafenib were planned. RESULTS Sixteen patients (4 low veff, median dose 51 Gy; 12 high veff, median dose 33 Gy) were treated at 2 sorafenib dose levels. Of those patients 75% were had Barcelona Clinic Liver Cancer stage C, and 63% had main branch portal vein invasion. In the low veff stratum, no dose-limiting toxicities (DLTs) were observed in 4 patients treated with SBRT and sorafenib 400 mg. Inb the high veff stratum: 2 of 3 evaluable patients treated with sorafenib 400 mg experienced DLT (grade 3 large bowel bleed and grade 4 bowel obstruction 51 and 27 days, respectively, after SBRT). One of 6 evaluable patients at dose level -1 (200 mg once daily) experienced a grade 3 tumor rupture at week 5. Median overall survival and in-field local progression have not been reached. Worsening of Child-Pugh liver function class was seen in 6 of 12 patients in the high veff stratum. CONCLUSIONS Significant toxicity was observed in the high veff stratum, and concurrent SBRT with sorafenib is not recommended outside a clinical trial.


Radiotherapy and Oncology | 2017

Phase I trial of radiation therapy and sorafenib in unresectable liver metastases

Rebecca B. Goody; Anthony Brade; Lisa Wang; Timothy J. Craig; James D. Brierley; R. Dinniwell; Rebecca Wong; Charles Cho; John Kim; Zahra Kassam; Jolie Ringash; Jennifer J. Knox; Laura A. Dawson

BACKGROUND AND PURPOSE To determine maximum tolerated dose (MTD) and toxicities of sorafenib combined with stereotactic radiotherapy (SBRT) or whole liver radiotherapy (WLRT) in patients with liver metastases. MATERIAL AND METHODS Eligible patients had unresectable liver metastases. Sorafenib dose was escalated in 2 strata: I - SBRT: effective liver volume irradiated (Veff)<80% (30-60Gy in 6 fractions); II - WLRT: Veff>80% (21.6Gy in 6 fractions). Four weeks of sorafenib, with radiotherapy during weeks 2-3, was delivered at 3 escalating dose levels (200-400mg twice daily). Dose limiting toxicity was defined as any grade 3+ liver toxicity, or grade 4+ treatment-related toxicity. RESULTS Thirty-three patients were treated: 18 in stratum I (median dose 42Gy), 15 in stratum II. The MTD was not reached. Grade 3+ toxicity was seen in 33% of patients, at a median of 10days. Two deaths from non-classic liver toxicity occurred post WLRT in stratum II. The median overall survival was 22.3 and 5.7months for strata I and II respectively. CONCLUSIONS Sorafenib and 21.6Gy in 6 fraction WLRT resulted in unacceptably high rates of liver toxicity. Although sorafenib combined with SBRT was tolerable, the observed efficacy does not merit further clinical evaluation.


Clinical Endoscopy | 2017

Characteristics of Missed Simultaneous Gastric Lesions Based on Double-Check Analysis of the Endoscopic Image

Eun Jeong Gong; Jeong Hoon Lee; Kyoungwon Jung; Charles Cho; Hee Kyong Na; Ji Yong Ahn; Kee Wook Jung; Do Hoon Kim; Kee Don Choi; Ho June Song; Gin Hyug Lee; Hwoon-Yong Jung; Jin-Ho Kim

Background/Aims The detection of multifocal lesions is important for the successful management of gastric neoplasms. We investigated the characteristics of missed simultaneous lesions and the reason for the missed diagnoses. Methods A total of 140 patients who underwent repeat endoscopy before endoscopic resection between June 2013 and June 2014 were retrospectively reviewed. We classified simultaneous lesions into three groups based on a review of earlier images: group 1, no images of the location of simultaneous lesions were taken; group 2, no corresponding lesion was evident in the previous images; and group 3, simultaneous lesions were visible in the earlier images but a biopsy was not performed. Results Simultaneous lesions were found in 12 patients (8.6%) with 13 lesions, comprising 10 dysplasia (76.9%) and three adenocarcinoma (23.1%). Regarding the reasons for missed diagnoses, seven lesions (53.8%) were classified as group 3, five (38.5%) as group 1, and the remaining lesion (7.7%) as group 2. There were no significant differences in the characteristics of the patients with and without simultaneous lesions. Conclusions Lesions disregarded or unnoticed during endoscopic examination were the main reason for missed diagnosis of simultaneous lesions. Endoscopists should consider the possibility of simultaneous lesions and attempt to meticulously evaluate the entire gastric mucosa.


PLOS ONE | 2017

Atrophic and Metaplastic Progression in the Background Mucosa of Patients with Gastric Adenoma

Hee Kyong Na; Charles Cho; Suh Eun Bae; Jeong Hoon Lee; Young Soo Park; Ji Yong Ahn; Do Hoon Kim; Kee Don Choi; Ho June Song; Gin Hyug Lee; Se Jin Jang; Hwoon-Yong Jung; Pal B. Szecsi

Background In patients with adenoma, assessing premalignant changes in the surrounding mucosa is important for surveillance. This study evaluated atrophic and metaplastic progression in the background mucosa of adenoma or early gastric cancer (EGC) cases. Methods Among 146 consecutive patients who underwent endoscopic resection for intestinal-type gastric neoplasia, the adenoma group included 56 patients with low-grade dysplasia and the ECG group included 90 patients with high-grade dysplasia or invasive carcinoma. For histology, 3 paired biopsies were obtained from the antrum, corpus lesser curvature (CLC), and corpus greater curvature (CGC). Serological atrophy was determined based on pepsinogen A (PGA), progastricsin (PGC), gastrin-17, and total ghrelin levels. Topographic progression of atrophy and/or metaplasia was staged using the operative link on gastritis assessment (OLGA) and operative link on gastric intestinal metaplasia assessment (OLGIM) systems. Results Rates of moderate-to-marked histological atrophy/metaplasia in patients with adenoma were 52.7%/78.2% at the antrum (vs. 58.8%/76.4% in EGC group), 63.5%/75.0% at the CLC (vs. 60.2%/69.7% in EGC group), and 10.9%/17.9% at the CGC (vs. 5.6%/7.8% in EGC group). Serological atrophy indicated by PGA and PGC occurred in 23.2% and 15.6% of cases in the adenoma and ECG groups, respectively (p = 0.25). Mean serum gastrin-17 concentrations of the adenoma group and EGC group were 10.4 and 9.0 pmol/L, respectively (p = 0.54). Mean serum total ghrelin levels were 216.6 and 209.5 pg/mL, respectively (p = 0.71). Additionally, between group rates of stage III–IV OLGA and OLGIM were similar (25.9% vs. 25.0%, p = 0.90; 41.8% vs. 44.9%, p = 0.71, respectively). Conclusions Atrophic and metaplastic progression is extensive and severe in gastric adenoma patients. A surveillance strategy for metachronous tumors should be applied similarly for patients with adenoma or EGC.


Clinical Endoscopy | 2018

Long-Term Survival and Tumor Recurrence in Patients with Superficial Esophageal Cancer after Complete Non-Curative Endoscopic Resection: A Single-Center Case Series

Ji Wan Lee; Charles Cho; Do Hoon Kim; Ji Yong Ahn; Jeong Hoon Lee; Kee Don Choi; Ho June Song; Sook Ryun Park; Hyunjoo Lee; Yong Hee Kim; Gin Hyug Lee; Hwoon-Yong Jung; Sung-Bae Kim; Jong Hoon Kim; Seung-Il Park

Background/Aims To report the long-term survival and tumor recurrence outcomes in patients with superficial esophageal cancer (SEC) after complete non-curative endoscopic resection (ER). Methods We retrieved ER data for 24 patients with non-curatively resected SEC. Non-curative resection was defined as the presence of submucosal and/or lymphovascular invasion on ER pathology. Relevant clinical and tumor-specific parameters were reviewed. Results The mean age of the 24 study patients was 66.3±8.3 years. Ten patients were closely followed up without treatment, while 14 received additional treatment. During a mean follow-up of 59.0±33.2 months, the 3- and 5-year survival rates of all cases were 90.7% and 77.6%, respectively. The 5-year overall survival rates were 72.9% in the close observation group and 82.1% in the additional treatment group (p=0.958). The 5-year cumulative incidences of all cases of recurrence (25.0% vs. 43.3%, p=0.388), primary EC recurrence (10.0% vs. 16.4%, p=0.558), and metachronous EC recurrence (16.7% vs. 26.7%, p=0.667) were similar between the two groups. Conclusions Patients with non-curatively resected SEC showed good long-term survival outcomes. Given the similar oncologic outcomes, close observation may be an option with appropriate caution taken for patients who are medically unfit to receive additional therapy.


Radiotherapy and Oncology | 2016

60: Outcomes of Esophageal Cancer Patients Treated with Trimodality Therapy in a Community Hospital

Catherine Vanderwater; Edwin Chan; Rachel Woo; Charles Cho; Jason Wong; Chris Arden; Geoff Liu; Beibei Zhang; Agnes Cheung; Alex Lee; Pravin Philip Chacko; Ehab Fadhel; Zahra Kassam

CARO 2016 _________________________________________________________________________________________________________ significance in either case. Bowel dysfunction in ACC is frequently attributed to treatment-related toxicity, however our data support the hypothesis that dysfunction is frequently multifactorial, including disease, comorbidity, and psychosocial factors in addition to treatment factors, and that adequate baseline assessment of function is essential prior to CRT.


Journal of Clinical Oncology | 2016

Efficacy and safety of endoscopic resection for gastric subepithelial tumors.

Kyoungwon Jung; Ji Yong Ahn; Do Hoon Kim; Eun Jeong Gong; Charles Cho; Hee Kyong Na; Jeong Hoon Lee; Kee Wook Jung; Kee Don Choi; Ho June Song; Gin Hyug Lee; Hwoon-Yong Jung; Jin-Ho Kim

107 Background: Because small gastric subepithelial tumors (SETs) less than 2.0 cm might have malignant potential, ambiguous cases should be removed for optimal diagnosis and treatment. With the recent advances in endoscopic technique, endoscopic resection (ER) has been attempted for pathologic confirmation of gastric SETs. Herein, we aim to investigate the clinical usefulness and safety of ER of gastric SETs. Methods: A total of 115 subjects who underwent ER for gastric SETs from January 2005 to December 2014 were eligible for the study at the Asan Medical Center, Seoul, Korea. Patient’s demographic status, tumor related factors, procedure related factors, and clinical outcomes were retrospectively reviewed by using electronic medical record. Results: Among the 115 patients, 53 were male (46.1%) and the mean age was 51.59 ± 14.59 years. The mean size of all tumors was 18.58 ± 10.71 mm. Complete endoscopic resection was achieved in 108 of 115 tumors (93.9%). The final histopathologic diagnoses included 38...


Journal of Clinical Oncology | 2015

Quality of life (QOL) in patients with esophageal cancer treated with radiation (RT) in the radical setting.

Anita Choudhary; Geoffrey Liu; Pravin Philip Chacko; Ehab Fadhel; Charles Cho; Rachel Woo; Agnes Cheung; Catherine Vanderwater; Cindy Xin; Wei Xu; Jason Wong; Alex Lee; Zahra Kassam

186 Background: QOL is poorly documented in patients with esophageal carcinoma treated with curative intent, especially trimodality therapy. QOL and survival outcomes were evaluated in a single centre prospective cohort study of esophageal carcinoma patients treated with RT in the radical setting. Methods: Patients completed the EORTC-QLQC30 at baseline, the end of RT, 6 months and 1 year after RT. A 10-point difference in scores was considered clinically significant. Results: Thirty-three of 45 consequently treated patients between February 2012 and June 2014 participated, all male, median age 63 years (range 40-76), with T1-4N1-3M0 disease (AJCC 7thedn), median follow up 0.9 years (range 0.1-2.3). Four patients were treated definitively with chemoradiation 45-50Gy in 25 fractions; 14 neoadjuvantly 45-50Gy in 25 fractions; 15 neoadjuvantly 41.4Gy in 23 fractions, with concurrent chemotherapy. Compliance for questionnaire completion was 80-100%. 2 year overall survival (OS) and disease free survival (DFS)...

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Zahra Kassam

University of Western Ontario

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James D. Brierley

Princess Margaret Cancer Centre

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R. Dinniwell

Princess Margaret Cancer Centre

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Jolie Ringash

Princess Margaret Cancer Centre

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Jason Wong

Princess Margaret Cancer Centre

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Laura A. Dawson

Princess Margaret Cancer Centre

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Rebecca Wong

Princess Margaret Cancer Centre

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