A single-institution experience on reirradiation of different tumor sites: preliminary results of the prospective study

ABSTRACT

Purpose: The aim of this single-center prospective study is to investigate the expediency of reirradiation of patients with different tumor localizations, taking into account the survival rates of patients, possible complications and subsequent quality of life.
Materials and methods: For the first time in Armenia, an analysis of the results of reirradiation is carried out on the basis of the experience of one clinic. The results of treatment of 1050 patients who received radiotherapy at the IRA Medical Group Medical Center from January 2019 to September 2021 were studied. The study included 42 patients who received a second course of radiotherapy, which accounted for 4% of the total number of patients. The median age of patients was 60.5 years (range, 2281), including 17 men, 25 women. According to pathologies: central nervous system primary tumors – 12 patients, brain metastasis – 8, gynecology – 6, head and neck tumors – 5, metastatic bone lesions – 3, breast cancer – 3, other localizations – 5. Stage of the disease: III – 6 patients, IV – 30, unclassified – 6.
The average interval between two courses of radiotherapy was 34.5 months (range, 1.5-252). The median total equivalent dose from two irradiation courses is 99 Gy (range, 56-121). Excluding patients who received reirradiation for metastatic relapse, the total equivalent dose was 102 Gy (range, 84-121), and the median follow-up time after reirradiation was 9 months (range, 4-29.5).
Results: The average life expectancy of patients who died during the observation period was 6.5 months (range, 1-23). In 7 out of 42 patients who initially had low Karnofsky score (60%), survival was up to 3.5 months. After excluding these patients from further statistical analysis, the median survival of the remaining patients was 10 months (range, 4-23). As of December 31, 2021, 21 patients (50%) were alive, with a mean follow-up of 11 months (range, 5-29.5). The number of post-radiation complications and the quality of life of patients were also assessed. There were no treatment-related deaths or reduced quality of life.
Conclusions: The preliminary results of this prospective study demonstrate that the use of the latest technologies in repeat radiotherapy can improve survival and quality of life of patients. Thanks to new technologies, it is possible to conduct a second course of radiotherapy even in curative doses. When planning a repeat therapeutic or palliative course of radiotherapy, it is necessary to carefully select patients, taking into account a number of factors related to previous treatment and individual characteristics of the patient. After completion of the study, we plan to develop recommendations on the criteria for selecting candidates for reirradiation.