Weekly large fraction radiotherapy and 5 fluorouracil as a palliative treatment for large bowel carcinoma: a pilot study

Palliative radiotherapy for large bowel cancer is generally given in fraction sizes of 2-3 Gy. Theoretical considerations led us to believe that a larger fraction size would not lead to a decreased response rate and practical considerations led us to treat patients once a week. The results of a pilot study of 32 patients with large bowel cancer are presented. Patients were treated with a fraction size of 6 Gy given weekly and combined with 5 FU. The response rate of 58% and the median survival of 9 months seems comparable with other regimens, as does the rate of acute side effects. The late high dose effect of subcutaneous fibrosis was seen in 30% of the long term survivors; the implications of this are discussed. We draw the conclusion that this treatment is convenient and effective in terms of tumor response, but that the late high dose effects were more severe than expected and that these effects may be potentiated by 5 FU.