Epidemiology of Resistant Cancer Pain: Prevalence, Clinical Burden, and Treatment Gaps.

Abstract

Background: Resistant cancer pain (RCP) remains a challenge in oncology, affecting patients whose pain persists despite guideline-based treatment. While advancements in pharmacological and interventional strategies have improved cancer pain management, barriers such as opioid access restrictions, provider knowledge gaps, and underutilization of specialized pain interventions contribute to inadequate relief. Understanding the epidemiology, classification, and risk factors for RCP is essential for improving treatment.

Summary: This review examines the prevalence, pathophysiology, and burden of RCP, highlighting its impact on quality of life and healthcare systems. Pain severity is commonly assessed using numerical rating scales, but comprehensive frameworks like the Edmonton Classification System for Cancer Pain (ECS-CP) provide better insight into complex pain syndromes. Breakthrough pain, neuropathic pain, and cancer-induced bone pain are frequently linked to treatment resistance. While opioids remain central to pharmacological management, many patients require multimodal approaches, including adjuvant analgesics, interventional procedures, and radiation therapy. Neurosurgical options such as cordotomy, intrathecal drug delivery, and myelotomy offer pain relief in select cases but are underutilized due to limited awareness and training.

Key messages: RCP remains a major unmet medical need, affecting many cancer patients despite advances in pain management. Effective treatment requires a multimodal, individualized approach integrating pharmacological, interventional, and neurosurgical strategies. While neurosurgical interventions provide substantial relief in selected patients, their use is often limited by referral delays and lack of provider awareness. Overcoming systemic barriers, refining pain classification, and expanding access to specialized pain management are essential to improving RCP care.