Combining cisplatin and mitomycin with radiotherapy in anal carcinoma

The European Organization for Research and Treatment of Cancer (EORTC) phase II study No. 22953 demonstrated the feasibility of reducing the overall treatment time of chemoradiation, delivering mitomycin C twice rather than once and fluorouracil during the whole treatment. We tested the feasibility of chemoradiation in anal carcinoma with mitomycin and cisplatin in a phase II study.

Twenty-one patients with locally advanced anal carcinoma (15 women, 6 men) were treated. The first sequence of radiotherapy consisted of 36 Gy over four weeks. After a gap interval of 16 days, a second sequence of radiotherapy was given, delivering 23.4 Gy over 2.5 weeks. Mitomycin C was delivered at 10 mg/m(2) day 1 of each sequence and cisplatin was delivered at 25 mg/m(2)/week of each sequence.

The compliance rates for the first sequence with radiation, mitomycinm, and cispaltin (dose and timing) were 100 percent. The median duration gap was 16 days (14-30 days). The compliance rates for the second sequence with radiation, mitomycin, and cisplatin (dose and timing) were 100, 76.2, and 85.7 percent, respectively. Grade > or = 2 acute toxicities of 62, 29, 25, and 5 percent were observed for skin, diarrhea, hematologic, and renal toxicities, respectively. Nineteen patients were in complete response (90.5 percent).

Combining radiation with mitomycin and cisplatin in patients with locally advanced anal cancer is feasible. The results are promising. The EORTC is currently comparing this combination with mitomycin and 5-fluorouracil in a large phase II-III trial.