REIRRADIATION FOR HEAD-AND-NECK CANCER: DELICATE BALANCE BETWEEN EFFECTIVENESS AND TOXICITY

Purpose: To analyze the effectiveness and toxicity of reirradiation (re-RT) for head-and-neck cancer. Methods and Materials: A retrospective data analysis was performed of 58 patients who underwent re-RT with curative intent. Re-RT was given as definitive treatment in 53% of patients, whereas salvage surgery preceded reirradiation in 47%. The median cumulative RT dose was 119 Gy (range, 76-140). Concurrent chemotherapy was administered with re-RT (CRT) in 57% of patients. Event-free survival was defined as survival without recurrence and without serious toxicity (>= Grade 3). Results: Median follow-up was 57 months (range, 9-140). Locoregional (LR) control was 50% at 2 and 5 years. The 2-year and 5-year overall survival (OS) was 42% and 34%. The following factors were associated with improved OS: postoperative re-RT (vs. primary re-RT), treatment with RT only (vs. CRT) and interval >3 years between previous RT and re-RT. For patients treated with postoperative re-RT and definitive re-RT, the 5-year OS was 49% and 20%, respectively. Patients treated with CRT had a 5-year OS of 13%. Serious (late) toxicity >= Grade 3 was observed in 20 of 47 evaluable patients (43%). Three cases of treatment-related death were recorded. The 2-and 5-year serious toxicity-free interval was 59% and 55%, respectively. Associated with increased risk of serious toxicity were CRT and higher re-RT dose. The event-free survival rates at 2 and 5 years were 34% and 31%, respectively. Conclusions: Re-RT in head-and-neck cancer is associated with poor survival rates of 13-20% in patients with inoperable disease treated with primary (chemo-) re-RT. For this subgroup, however, no other curative options are available. Long-term disease control and survival can be achieved in patients who receive re-RT as an adjunct to surgical resection. The rates of serious toxicity after re-RT are high, with an incidence of approximately 45% at 5 years. Approximately 1 in 3 patients survived re-RT without recurrence and severe complications.