Radiotherapy side effects: integrating a survivorship clinical lens to better serve patients

The Canadian Cancer Society estimated that 220,400 new cases of cancer would be diagnosed in 2019. Of the affected patients, more than 60% will survive for 5 years or longer after their cancer diagnosis. Furthermore, nearly 40% will receive at least 1 course of radiotherapy (rt). Radiotherapy is used with both curative and palliative intent: to treat early-stage or locally advanced tumours (curative) and for symptom management in advanced disease (palliative). It can be delivered systemically (external-beam rt) or internally (brachytherapy). Although technique improvements have drastically reduced the occurrence of rt-related toxicity, most patients still experience burdensome rt side effects (seffs). Radiotherapy seffs are local or locoregional, and manifest in tissues or organs that were irradiated. Side effects manifesting within weeks after rt completion are termed "early seffs," and those occurring months or years after treatment are termed "late seffs." In addition to radiation oncologists, general practitioners in oncology and primary care providers are involved in survivorship care and management of rt seffs. Here, we present an overview of common seffs and their respective management: anxiety, depression, fatigue, and effects related to the head-and-neck, thoracic, and pelvic treatment sites.