POSSIBILITIES OF REIRRADIATION IN PATIENTS WITH RECURRENT SQUAMOUS CELL CARCINOMA OF HEAD AND NECK

Abstract

Locoregional recurrence is the most frequent cause of death of patients with SCCHN. At present day clear guidance on the irradiation volume, total dose and timing of radiation re-treatment of these patients are missing. 20 patients with histologically confirmed locoregional recurrence of HNSCC, received reirradiation. Median time after primary radiotherapy course was 37 months. The treatment volumes and total doses were formed as follows: GTV (primary lesion and involved lymph nodes, delineated on CT, MRI and 18 F-FDG PET-CT)+CTV (0,5–1,0 cm) + PTV (0,3–0,5 cm) was treated to the total dose equivalent to 66–70 Gy of conventional fractionation, the upper neck (if indicated, levels I–III+PTV 0,5 cm) to 60 Gy, the lower neck (if indicated, levels IV–V+PTV 0,5 cm) — equivalent to 50 Gy. Single doses to these volumes were 2,14–2,21 Gy, 2,0 Gy and 1,8 Gy, respectively. Treatment was planned using IMRT and VMAT techniques with SIB (Simultaneously Integrated Boost). Daily positioning inaccuracy was less than 3 mm at lymph nodes PTV and less than 1 mm in OARs of CNS and optic pathways. 19 of 20 patients received full course of radiation therapy without a break. Radiation toxicity manifested with grade 2 oral and pharyngeal mucositis and grade 2 radiation epidermitis. Relief time of radiation mucositis and dermatitis was the same to primary radiotherapy course. Oneyear OS was 48%. Using technique of SIB with IMRT and VMAT during curative reirradiation of recurrent HNSCC is available with maintaining satisfactory tolerability.