Evaluation of neuropathic pain with diverse pathophysiologies in childhood cancers

Neuropathic pain (NP) is caused by damage or disease affecting the somatosensory nervous system. The aim of this study was to evaluate the clinical characteristics, pathophysiologies, and treatments applied in pediatric cancer patients with NP.

Patients with cancer having NP between 5 and 18 years of age who were followed up in the pediatric oncology clinic of Okmeydani Training and Research Hospital between January 2015 and April 2019 were included in this study. NP was described as tingling, burning, and stinging. Patients with acute lymphoblastic leukemia and brain tumors were excluded from the study. A number of pediatric cancer patients were also recorded. Patients' age, gender, cancer diagnosis, NP characteristics and causes, treatments, and response to those treatments were investigated retrospectively and groups of NP according to their pathophysiological mechanism were established.

NP was found in 26 (16%) of 160 patients followed up for childhood cancers. The average age was 11.8±4 years. Ten of the patients (38.4%) were female, and 16 (61.5%) were male. Osteosarcoma was the most common diagnosis in 10 (38%) patients. The most common cause of NP was compression of a nerve/root/spinal cord in 9 (35%) patients and the second most common was related with limb-sparing surgery. NP was found to be associated with chemotherapy (CT) in 5 (19%) patients, mostly with vincristine. Gabapentin was administered in a total of 22 (85%) patients for treatment. Opioid administration was more common as the disease stage progressed (p<0.05). A good or partial response to treatment was achieved in 19 (73%) patients.

NP can occur in childhood cancers and is related to the cancer itself, CT, surgical treatment, and disseminated disease. Although there is no standard protocol, gabapentin and, for advanced-stage patients, opioids are the most commonly used treatment options.