A comparison between 5-fluorouracil/mitomycin and capecitabine/mitomycin in combination with radiation for anal...

There are no randomized phase III trials comparing 5-fluorouracil/mitomycin (FM) versus capecitabine/mitomycin (CM) in combination with radiotherapy (RT) for locally advanced anal cancer. We aim to evaluate the outcomes of patients treated with FM and CM at our institution.

Patients with stage I-III anal cancer who initiated curative-intent RT (50-54 Gy) with either CM or FM between 1998 and 2013 at the BC Cancer Agency were reviewed. Cox proportional models were used to analyze the impact of regimen on disease-free survival (DFS) and anal cancer-specific survival (ACSS).

A total of 300 patients were included. Baseline characteristics were well-distributed between the groups. A total of 194 patients (64.6%) received FM and 106 (35.3%) CM. The 2-year DFS was 79.7% for CM [95% confidence intervals (95% CI), 71.1-88.3%] and 78.8% for FM (95% CI, 73-84.6%); 2-year ACSS was 88.7% for CM (95% CI, 81.8-95.5%) and 87.5% for FM (95% CI, 82.8-92.2%). On multivariate analysis, only HIV status, clinical T size (≤5 vs. >5 cm), and N status (negative vs. positive) remained as significant prognostic factors for both DFS and ACSS. Chemotherapy regimen (CM vs. FM) had no impact on either DFS [P=0.995; hazard ratios (HR) =0.99; 95% CI, 0.57-1.74] or ACSS (P=0.847; HR =0.93; 95% CI, 0.46-1.86).

In our population-based study, CM and FM concomitant with RT achieved similar DFS and ACSS. Substitution of capecitabine for infusional 5-FU may therefore be a reasonable option for patients and physicians who prefer to avoid the inconvenience and potential complications of a central infusional device.