[Chemoradiotherapy in treatment of cancer of the anal canal]

[Conservative treatment of anal canal carcinoma with external radiotherapy and interstitial brachytherapy, with or without chemotherapy: long-term results]

PURPOSE

A retrospective analysis of conservative treatment of anal canal cancers with external radiation therapy and interstitial brachytherapy with or without chemotherapy.

PATIENTS AND METHODS

From 1986 to 1996, 69 patients were treated with external radiotherapy (40 Gy/20 fractions) and interstitial brachytherapy (20 Gy) after a mean interval of six weeks for a localized epidermoid carcinoma of the anal canal. Patients who did not complete the whole therapeutic sequence were not included. Forty-five patients received additional 5-fluorouracil- and/or mitomycin C-based chemotherapy regimen.

RESULTS

Acute toxicity was acceptable. Complete response rate was 81%. Actuarial local control rate was at two and five years, 65% and 59% respectively (median follow-up: eight years). At two, five and ten years, actuarial colostomy rate was 26%, 33% and 33% respectively, and colostomy-free survival rates 61%, 47% and 37%. Overall survival at two, five and ten years was 81%, 65% and 53% respectively. Distant metastases occurred in 11 patients (16%). Prognostic factors for overall survival were performance status (PS) (79% survival at five years for patients with PS 0 versus 50% for patients with PS 1-3, P = 0.04) and tumor stage (80% at five years for T1-T2 versus 53% for T3-T4, P = 0.03). Overall treatment time less than 12 weeks and time interval between external radiotherapy and brachytherapy inferior than six weeks were associated with a better local control (P = 0.05). In multivariate analysis, these prognostic factors were not significant.

CONCLUSION

These results confirm the efficacy of external radiotherapy and brachytherapy in the treatment of small anal canal cancers, and point out the need for improving treatment outcome of larger tumors.