Adjuvant simultaneous integrated boost IMRT for patients with intermediate- and high-risk head and neck cancer: outcome, toxicities and patterns of failure

Abstract

Objectives: To evaluate loco-regional control, survival, toxicities and patterns of failure of adjuvant intensity-modulated radiotherapy (IMRT) with a simultaneous integrated boost (SIB) for head and neck cancer (HNC) patients according to risk features.

Materials and methods: 129 HNC patients who were treated between January 2001 and June 2010 at our institute with adjuvant SIB-IMRT with or without concurrent chemotherapy (CTX-SIB-IMRT) were included. High-risk (HR) patients with extracapsular tumor extension (ECE) and/or close resection margins had CTX-SIB-IMRT to 54/63.9 Gy and intermediate-risk (IR) patients had SIB-IMRT to 50/56 Gy. The primary endpoints were local (LC) and regional control (RC). Secondary endpoints included distant control rate (DC), overall survival (OS), acute and late toxicities and patterns of failure.

Results: 79/129 Patients were HR. 50/129 patients IR. 5-year LC was 87% and 89%, RC was 97% and 86%, DC was 95% and 77% and the OS 73% and 67% for IR and HR respectively. 43 deaths occurred. Acute toxicity CTCAE⩾grade 3 was observed in 55% and 56% and late toxicities in 10% and 15% of the IR and HR-group respectively. Fifteen patients developed loco-regional failure.

Conclusion: We observed significantly more patients with distant metastases in the HR group and no difference in LC, RC or OS between the two groups. The majority of the analyzed recurrences were in-field, in the high dose volume. Acute and late toxicity was moderate.

Keywords: Head and neck cancer; Intermediate-risk; Postoperative IMRT; Simultaneous integrated boost.