Overview of radiotherapy-induced chronic pain in childhood cancer survivors: A narrative review.

Radiotherapy is an important aspect of oncological treatment in several childhood cancers. However, radiotherapy is known to have numerous side effects, including detrimental effects on growth, neurocognitive impairment, and the development of secondary malignancies. One less studied long-term side effect of pediatric radiotherapy treatment is chronic pain. While the short-term toxicities of radiotherapy resolve over a few weeks to months, the chronic pain caused by radiotherapy-induced tissue damage can significantly affect children's quality of life. As long-term childhood cancer survivors age into adulthood, they are typically followed up by a wide variety of doctors, not all of whom may be familiar with radiotherapy-induced chronic pain and its management. The aim of this review is to discuss the various common manifestations of radiotherapy-related pain in children, as well as ways to identify and manage these. Common radiotherapy-related side effects leading to chronic pain symptoms include radiation fibrosis, enteritis, dermatitis, lymphedema, neuropathic pain, and effects on bone development. The pathophysiology, evaluation and management of these are briefly summarized in this review. This is followed by an overview of radiotherapy techniques that allow greater sparing of normal tissue, minimizing future painful side effects. Finally, the assessment of pain in children is described, as well as strategies for management, and red flag symptoms that should prompt urgent specialist referral. In conclusion, a good understanding of the long-term side effects of radiotherapy treatment in children is essential for the various medical professionals that follow-up the child in the years after treatment. For young children, the evaluation of pain is in itself a challenge, and effects on growth, development, and learning are crucial. For older children, social and psychological factors become increasingly important. As radiation therapy techniques continue to advance, the spectrum and incidence of chronic pain syndromes may change over time.