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Biomedical subjects

J O Gage

Publications and source records attributed to J O Gage.

8 recordsLinked to original sources
PubMed1996

Postoperative radiotherapy for locally advanced colon cancer.

BACKGROUND: The role of adjuvant postoperative radiotherapy for locally advanced colon cancer is not well documented. METHODS: Seventy-eight patients who underwent a complete resection of B2-C colon cancer received postoperative radiotherapy. Twenty-eight patients received < or = 45 Gy; 50 patients received 50-55 Gy. Twenty-seven patients received adjuvant fluorouracil-based chemotherapy. All patients were followed for a minimum of 3 years; no patients were lost to follow-up. RESULTS: The overall local control rate was 88%. The 5-year actuarial rate of local control was 96% after 50-55 Gy postoperative radiotherapy compared with 76% after < 50 Gy (p = 0.0095). Multivariate analysis of local control showed that only radiotherapy dose significantly influenced this end point. Cause-specific survival rates at 5 years were B2, 67%; B3, 90%; C1, 100%; C2, 61%; C3, 36%; and overall, 63%. Multivariate analysis of cause-specific survival showed that only stage significantly influenced this end point. Bowel obstruction caused by adhesions developed in three patients and required a laparotomy; radiation-induced sarcoma developed in one additional patient. CONCLUSIONS: Postoperative radiotherapy appears to reduce the risk of local recurrence in patients with locally advanced colon cancer. The optimal dose is probably 50-55 Gy at 1.8 Gy per fraction. Postoperative radiotherapy may improve cause-specific survival for patients with stages B3 and C2 cancers.

Adenocarcinoma↗
PubMed1973

Influence of tumour growth on the evolution of cytotoxic lymphoid cells in rats bearing a spontaneously metastasizing syngeneic fibrosarcoma.

Regional and distant lymph node cells, thoracic duct cells and peripheral blood lymphocytes from rats bearing a spontaneously metastasizing and apparently non-immunogenic sarcoma were assayed for cytotoxic activity on microcultures of tumour cells at 7, 14 and 21 days of tumour growth. In the regional lymph nodes detectable cytotoxicity was present at 7 days and the overall activity remained constant at 14 and 21 days. At Day 7 of tumour growth the cytotoxic cell population in the regional node was tumour specific in its cytotoxic effect, very radiosensitive and could not be removed by nylon wool column purification. In contrast the cells in the regional nodes at Day 21 were nonspecifically cytotoxic and could be completely removed by nylon wool treatment. In the peripheral blood, cytotoxic lymphoid cells not removed by nylon wool, were detectable at all stages of tumour growth. The thoracic duct lymph cells were, however, without cytotoxic activity throughout the period of tumour growth studied. Distant lymph node cells were assayed for cytotoxicity and it was found that they acquired significant cytocidal properties only late in tumour growth. The sera from tumour-bearing rats were tested for inhibitory activity on the cytotoxicity of Day 7 regional lymph nodes from tumour-bearing rats. It was found that a specific inhibitor appeared in the serum and that its activity increased with tumour growth. The possible contributions of the changes in lymph node cytotoxicity and the development of specific serum inhibitors to continued growth and dissemination of the tumour are discussed.

Animals↗