Hyperfractionation in the reirradiation of head and neck cancers. Result of a pilot study.

Between November 1988 and May 1992, 19 patients were enrolled in a pilot study to evaluate feasibility and results of a hyperfractionated reirradiation in the treatment of head and neck recurrences or second primary tumors developed in previously irradiated volume. Patients were divided in two groups according to the initial treatment before reirradiation: group 1 included 14 patients treated with radical surgery and reirradiated because histological evidence of positive margins and/or extra capsular spread of tumor in lymph node metastases; group 2 included five patients treated with three cycles of CDDP-5FU for unresectable tumors and reirradiated because they experienced a complete or good partial (> or = 80%) response after chemotherapy. The reirradiation planned dose was 60 Gy in 5 weeks, with two daily fractions of 1.2 Gy spaced by 6-8 h intervals. Reirradiation was delivered exclusively with photon beams in 17 cases and with a combination of photon and electron beams in two cases. Follow-up ranged from 3 to 45 months with a median of 17 months. Of the 19 patients, 13 received the reirradiation scheduled dose of 60 Gy. For the six remaining patients, the reirradiation doses ranged from 45.6 to 57.6 Gy. All patients experienced an acute mucositis which never led to interruption of treatment. Of the 14 patients of group 1, 10 died 3-41 months after reirradiation (mean: 14 months), three were disease-free 16-37 months after reirradiation and one patient was alive with local progressive disease 39 months after the reirradiation. The overall local control within reirradiated volume was 36% before and 43% after salvage surgery. For all group 1 patients, 12- and 24-month overall survival was 64 and 36%, respectively (mean: 21 months). All patients of group 2 presented a local failure within the reirradiated volume. Three of them died 12, 16 and 25 months after reirradiation, while two of them were alive with progressive disease 25 and 30 months after reirradiation, respectively. The mean survival was 22 months. Overall, 15 late complications were noted: five grade 1, eight grade 2 and two grade 3. There was no lethal complication. Four patients alive in September 1993, and whose initial technical files were available, were enrolled in an additional study to assess the cumulative doses delivered by the two irradiations. Despite disappointing loco-regional control rates, a reirradiation of 60 Gy using a hyperfractionated schedule is feasible in terms of acute and late toxicity.