Premature discontinuation of curative radiotherapy: insights from head and neck irradiation

Abstract Background Factors related to premature discontinuation of curative radiotherapy (PDCRT) are understudied. This study aimed to examine causes and clinical outcomes of PDCRT at our institution through investigating the most common anatomical site associated with PDCRT. Methods Among 161 patients with PDCRT of various anatomic sites at our institution in the period 2010-2017, 36% received radiation to the H&N region. Pertinent demographic, clinical, and treatment-related data on these 58 patients were collected. Survival was examined using the life-table method and log-rank test. Results The majority of patients were men (81%), white (67%), ≥ 60 years old (59%), living ≥ 10 miles away from the hospital (60%), single (57%), with Eastern Cooperative Oncology Group score ≥1 (86%), experiencing significant pain issues (67%), and had treatment interruptions in RT (66%). The most common reasons for PDCRT were discontinuation against medical advice (DAMA) (33%), medical comorbidity (24%), and RT toxicity (17%). Of comorbidities leading to PDCRT, 50% were acute cardio-pulmonary issues, and 43% - infection. Mean follow-up time was 15.9 months. 2-year overall survival and disease-specific survival rates were 61% and 78%, respectively. Patients with illicit substance abuse, cardiovascular disease, and ECOG ≥2 had worse survival. There was a trend toward improved survival with total completed dose ≥ 50 Gy vs < 50 Gy, 74% vs 44% (p=0.07). Conclusions In this largest to-date modern analysis of PDCRT, the most common cause of discontinuation was DAMA, which underscores the importance of patient education, optimization of RT symptoms, involvement of social work and integration of other supportive services early in treatment. Survival remains suboptimal after PDCRT for H&N tumors, with 2-year OS rate at 61%. Completing >50 Gy appears to confer a relative therapeutic benefit.