To determine the frequency, factors and reasons of patient non-adherence to radiotherapy (RT) in a tertiary cancer centre.

Inadvertent treatment interruptions often lead to prolongation of planned treatment time. In the case of RT with a curative intent, prolongation of planned treatment has been associated with inferior clinical outcomes. Delay or prolongation of treatment is associated with a relative risk of local recurrence by up to 2% per day for specific malignancies. Thus, it is critical to understand key factors that influence non-adherence to RT.

A retrospective observation audit was conducted comprising patients treated with radical, adjuvant or palliative RT at our centre from January 2018 to December 2018. Non-adherence was defined as premature permanent termination of planned treatment by the patient without recommendation or consultation from the treating clinician. All data were collected and analysed (retrospectively) with the help of Statistical Package for the Social Sciences (SPSS) version 22.

A total of 1,548 patients were included in the study of which 105 (6·7%) were non-adherent to planned RT. Of the total 105 patients, 44 (42%) were elderly (60 years and above). Treatment non-adherence was predominant in males (male:female = 1·85:1). More than 90% of non-adherent patients had stage III and IV cancer. A total of 77 patients (74%) out of 105 were more than 50 km away from our centre. A total of 66 (63%) out of 105 patients had completed more than 2 weeks of radiation (40% of planned RT) and then defaulted for radiation due to acute toxicities.

Treatment adherence is a major factor in determining successful outcomes among cancer patients treated with RT. This study reveals several factors that contribute to non-adherence to treatment.