G.M. Thomas
Ontario Institute for Cancer Research
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International Journal of Radiation Oncology Biology Physics | 1982
G.M. Thomas; Walter D. Rider; Alon J. Dembo; B.J. Cummings; Mary Gospodarowicz; N.V. Hawkins; James G. Herman; Colin W Keen
Four hundred and forty-four patients with the histological diagnosis of pure seminoma were treated at The Princess Margaret Hospital between 1958 and 1976. Using the Walter Reed Hospital staging classification, 338 patients (76.1%) were Stage I, 86 (19.4%) were Stage II, and 20 (4.7%) were Stage III. The 5 year actuarial survival rate (5 yr Sa) for all stages was 87%, and for Stages I, II and III: 94%, 74% and 32% respectively. In Stage II the 5-year Sa was significantly worse when palpable abdominal disease was present (62%, vs 87% when it was absent, p less than .02). Prophylactic mediastinal irradiation was not used for patients with Stage II disease. None of 40 Stage II patients without palpable abdominal disease recurred in the non-irradiated mediastinum. Ten of 46 Stage II patients with palpable abdominal disease recurred in the mediastinum; 7 of the 10 were cured with mediastinal irradiation at the time of relapse. Prophylactic mediastinal irradiation appears unnecessary in Stage II patients. The Stage III category includes a subgroup of patients who were curable with radiation therapy:L 5/6 with supradiaphragmatic nodal disease without palpable abdominal or visceral disease were cured. Exploration of new treatment methods appears indicated for the salvage of patients recurring in sites other than the mediastinum or supraclavicular fossa and for patients presenting with visceral disease.
Diseases of The Colon & Rectum | 1983
Bernard Cummings; Walter D. Rider; Andrew R. Harwood; Thomas J. Keane; G.M. Thomas
External beam megavoltage radiation therapy was used as primary treatment for 123 patients with rectal adenocarcinoma. Surgery was undertaken for some patients who had residual tumor. The overall five-year survival rate was 21 per cent. When patients were separated into those who presented with clinically mobile and those with clinically fixed rectal tumor masses, the survival rates were 38 per cent and 2 per cent, respectively. The primary tumor was controlled by radiation alone in 21 of 56 (38 per cent) patients who had mobile tumors but in only six of 67 (9 per cent) patients who had fixed tumors. Further investigation of high-dose primary radiation, with surgery reserved for patients with residual rectal carcinoma, may allow reduction of the number of patients who require abdominoperineal resection.
Diseases of The Colon & Rectum | 1982
Bernard Cummings; G.M. Thomas; Thomas J. Keane; Andrew R. Harwood; Walter D. Rider
A retrospective analysis was undertaken of 51 patients with primary anal canal carcinoma who were treated by radiation therapy, with surgery being reserved for those with residual carcinoma. The five-year uncorrected survival rate was 59 per cent, and the corrected survival rate was 71 per cent. The primary tumor was controlled by radiation alone in 29 of 51 patients (57 per cent) and by subsequent radical surgery in eight of ten patients. Abnormal lymph nodes were controlled by radiation alone in eight of 11 patients. Only three of 29 patients required surgery for complications associated with radiation in the absence of persistent tumor. Seventy-seven per cent (23 of 30) of long-term survivors did not require colostomy and retained anal continence. It is concluded that modern radiation therapy techniques are well tolerated and are an effective method of treating carcinoma of the anal canal.
International Journal of Radiation Oncology Biology Physics | 1980
Thomas J. Keane; W.D. Rider; Andrew R. Harwood; G.M. Thomas; B.J. Cummings
Abstract Twenty-eight patients with metastatic gastrointestinal carcinoid tumor were treated with whole abdominal radiation. Twenty-one of these patients had the carcinoid syndrome. The prescribed mid-line tumor dose was 2000 to 2500 rad. in 20 to 25 fractions in 4 to 5 weeks. The overall 5 year survival was 35% (median survival 2.5 years). A marked survival difference was noted in those patients with carcinoid syndrome compared to the non-functioning group. None of the syndrome patients survived five years (median survival 1.7 years) whereas six of the seven non-syndrome patients are five year survivors.
Diseases of The Colon & Rectum | 1980
Bernard Cummings; Andrew R. Harwood; Thomas J. Keane; G.M. Thomas; Walter D. Rider
Radical radiation therapy combined with 5-fluorouracil and mitomycin-C was studied in six patients with previously untreated operable squamous cell carcinoma of the anal canal. All six patients achieved local tumor control and have retained anal continence. There has been no evidence of late recurrence to date. This preliminary report demonstrates that this method of treatment warrants further study.
International Journal of Radiation Oncology Biology Physics | 1985
C.S. Wong; Andrew R. Harwood; B.J. Cummings; Thomas J. Keane; G.M. Thomas; W.D. Rider
A retrospective analysis of 82 patients with cancer of the colon above the peritoneal reflection who received postoperative local abdominal irradiation was undertaken to assess the survival, patterns of failure, and toxicity of treatment. Forty-eight patients (adjuvant group) had a complete resection, but were felt to be at high risk for local relapse and received postoperative local abdominal irradiation. Thirty-four patients had gross residual disease following surgery. The 5-year actuarial survival and local relapse free survival were 67 and 67%, respectively, in the adjuvant group. In this group, local relapse was observed in 9 of 28 patients with Stage C disease in contrast to 3 of 20 patients with Stage B2 disease; 1 of 14 patients with lesions in the right colon failed locally compared to 11 of 35 patients with lesions in the left. Only 2 of the 34 patients with gross residual disease remained relapse free from 93% of patients having a component of local failure. The majority of the treatment morbidity was seen in patients with gross residual disease. Prospective randomized studies should be done to determine the efficacy of postoperative irradiation in patients with colon carcinoma who are at high risk for local recurrence following surgical resection.
Diseases of The Colon & Rectum | 1982
N. F. Boyd; Bernard Cummings; Andrew R. Harwood; Walter D. Rider; G.M. Thomas
To examine the reliability of clinical features as possible components of a clinical method of prognostic staging for patients with rectal cancer, the results obtained when two pairs of physicians interviewed and examined a consecutive series of 60 patients with unresected rectal cancer were compared. High levels of agreement between physicians were found for most items of the patient’s history, on whether the lesion was palpable, on the distance of the tumor from the anus, on the location and circumferential extent of the tumor, and on whether the tumor was fixed or mobile. Although physicians elicited similar physical signs, thier use of terms to describe the rectal lesions varied widely unless agreed-upon criteria were used. There was 63 per cent agreement on the use of descriptive terms among physicians using criteria and only 13 per cent agreement among physicians not using criteria. These results show that prognostically important clinical features in patients with rectal cancer can be reliably identified and are thus suitable for inclusion in methods of clinical prognostic staging for this disease.
International Journal of Radiation Oncology Biology Physics | 1984
Thomas J. Keane; Andrew R. Harwood; W.D. Rider; B.J. Cummings; G.M. Thomas
International Journal of Radiation Oncology Biology Physics | 1981
B.J. Cumminas; W.D. Rider; Andrew R. Harwood; Thomas J. Keane; G.M. Thomas
International Journal of Radiation Oncology Biology Physics | 1978
W.D. Rider; N.V. Hawkins; B.J. Cummings; Andrew R. Harwood; G.M. Thomas