Accelerated hyperfractionated irradiation for advanced head and neck cancer: effect of shortening the median treatment duration by 13 days.

Abstract

Optimal treatment duration of altered fractionation schedules in head and neck cancer is still undefined. A retrospective study on local tumor control, survival, and complications of accelerated hyperfractionated irradiation in head and neck cancer was undertaken to investigate whether there was an advantage in further shortening overall time from 6.5 weeks. Four hundred nineteen consecutive male patients treated with radiation alone for cure 1987-1998 were analyzed. Patients with stage I, or treated also with brachytherapy implants or chemotherapy, were excluded. Treatment with accelerated hyperfractionation was performed twice daily, at a median of 1.6 Gy/fraction, to a total median dose of 68 Gy in 39 days. The patient population was divided into two groups: those with < or =39 days overall treatment time (group A, n = 227; median, 33 days) and those with >39 days (group B, n = 192; median, 46 days). Group A received a significant median tumor dose reduction of 7% compared with group B. The 7-year actuarial local control (LC) rates were 59% and 48% for groups A and B, respectively (p =.02). The actuarial LC rates for T1-2 patients were 79% and 74% at 7 years for groups A and B, respectively (p = NS). Similarly, for T3-4 patients, they were 47% and 35% (p =.02), respectively. The 7-year actuarial disease-free survival (DFS) rates for groups A and B were 39% and 26% (p =.01), respectively. For stage II patients, DFS was 62% and 60% at 7 years (p = NS) for groups A and B, respectively. And similarly, for stage III-IV patients, DFS was 33% and 20% (p =.04), respectively, at 7 years. LC and DFS rates at 7 years for T4 and stage IV patients, respectively, were significantly improved in group A. Cox regression analyses for LC showed that both T stage and overall time were significant prognostic factors. Similarly, UICC clinical stage and overall time were significant prognostic factors for DFS. There was no difference in acute morbidity between the two groups: 3% of patients in both groups required tube or parenteral feeding. The 7-year actuarial probability of RTOG/EORTC grades 3-5 late effects was 15% and 13%, respectively, for each group (p = NS). This study, with the limitations of a retrospective study, has shown a significant improvement in local tumor control and disease-free survival, in patients treated with shorter overall treatment times (median, 33 days) with an accelerated hyperfractionated irradiation schedule compared with those treated with a median duration of 46 days. No significant enhancement of acute reactions and late morbidity were observed with the shorter schedule.