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 pil ot study to evaluate feasibility and results of a hyperfractionated re irradiation in the treatment of head and neck recurrences or second pr imary tumors developed in previously irradiated volume, Patients were divided in two groups according to the initial treatment before reirra diation: 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 incl uded five patients treated with three cycles of CDDP-5FU for unresecta ble tumors and reirradiated because they experienced a complete or goo d partial (greater than or equal to 80%) response after chemotherapy. The reirradiation planned dose was 60 Gy in 5 weeks, with two daily fr actions of 1.2 Gy spaced by 6-8 h intervals. Reirradiation was deliver ed 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 th e reirradiation scheduled dose of 60 Gy. For the six remaining patient s, the reirradiation doses ranged from 45.6 to 57.6 Gy. All patients e xperienced an acute mucositis which never led to interruption of treat ment. Of the 14 patients of group 1, 10 died 3-41 months after reirrad iation (mean: 14 months), three were disease-free 16-37 months after r eirradiation and one patient was alive with local progressive disease 39 months after the reirradiation. The overall local control within re irradiated volume was 36% before and 43% after salvage surgery. For al l group 1 patients, 12- and 24-month overall survival was 64 and 36%, respectively (mean: 21 months). All patients of group 2 presented a lo cal failure within the reirradiated volume. Three of them died 12, 16 and 25 months after reirradiation, while two of them were alive with p rogressive 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 letha l complication. Four patients alive in September 1993, and whose initi al technical files were available, were enrolled in an additional stud y to assess the cumulative doses delivered by the two irradiations. De spite disappointing loco-regional control rates, a reirradiation of 60 Gy using a hyperfractionated schedule is feasible in terms of acute a nd late toxicity.