Vulnerability and Risk of Neuropathic Pain in Cancer

Successive and repeated therapeutic interventions during cancer management - surgery, chemotherapy, radiotherapy - can all, to varying degrees, generate acute pain, central pain sensitization and chronic pain. Almost 58% of patients suffer from chronic pain, often of the neuropathic type, with altered quality of life and disease burden amplified by difficulty in achieving effective relief. Indeed, neuropathic pain in cancer remains difficult to treat, often arrives insidiously, may persist well beyond cancer remission, and frequently has a fate that is difficult to predict. Current treatments for neuropathic pain are based on the recommendations of learned societies, but therapeutic failures are frequent, and iatrogenic pathology is high. Many factors have been identified as being associated with the development of chronic pain in cancer patients. The intensity of preoperative pain, opioid consumption, age, sleep disorders, cognitive-emotional state, psychological vulnerability and social precariousness are all factors that influence and perpetuate chronic pain linked to cancer and its management. Several studies have shown that 6 months or 1 year after cancer diagnosis, there are various pain trajectories, enabling us to identify several pain patient phenotypes. The patient's overall state of vulnerability at the time of cancer diagnosis has an impact on the trajectory of pain chronicisation, and it is often difficult for clinicians to apprehend this risk. In practice, we lack a validated, easy-to-use tool that would enable us to predict the risk of pain chronicisation for each patient, even before the start of the treatment process.