Chemoradiotherapy combined with intracavitary hyperthermia for anal cancer: feasibility and long-term results from a phase II randomized trial

Abstract

Purpose: The purpose of this study was to investigate in a randomized way the clinical benefit of addition of intracavitary hyperthermia (ICHT) to a conventional chemoradiotherapy schedule in patients with T2-T3N0M0 anal cancer.

Methods and materials: Patients were randomly assigned to undergo chemotherapy with 5-fluorouracil (5-FU) and mitomycin-C combined with radiotherapy with (arm A: 24 patients) or without ICHT (arm B: 25 patients). A microwave applicator operating at 433 MHz inserted into the anal-rectal cavity was used for ICHT. Patients in both arms received 1000 mg/m2 per day of 5-FU on days 1-4 and days 28-31 plus 15 mg/m mitomycin-C on day 1. Radiotherapy was administered with a dose of 41.4 Gy (1.8 Gy per fraction) plus a booster dose of 14 Gy (2 Gy per fraction).

Results: One patient from group A developed severe mucositis, whereas no severe morbidity was noted in the rest of the patients in both groups. The incidence of lower-intestine acute reactions was higher in the ICHT arm. After a 5-year follow up in the hyperthermia arm, 23 of 24 patients (95.8%) preserved their anorectal function and avoided permanent colostomy, whereas in the second arm, 17 of 25 (68.0%) had sphincter preservation. Local recurrence-free survival time was significantly higher in the ICHT arm (P = 0.0107, log rank test), whereas no significant difference in overall survival was noted.

Conclusion: The addition of ICHT to the chemoradiotherapy schedule of anal cancer seems to offer a new effective and safe therapeutic modality. The preservation of anorectal function seems to be the significant clinical benefit of adjuvant ICHT.