Diagnosing neuropathic pain in patients with cancer: comparative analysis of recommendations in national guidelines from European countries.

Background: Neuropathic pain is a prevalent symptom in patients with cancer, which needs a more specific algorithm than nociceptive pain or neuropathic pain from other origin. Clinical practice guidelines (CPGs) can be helpful in optimizing the diagnosis of neuropathic pain in patients with cancer.

Methods: In this study, 9 national CPGs in Europe on the diagnosis of neuropathic pain in patients with cancer were included. Recommendations with their grade (according SIGN 55 classification) and supporting literature (first author, patients' population, year, and type of publication) were compared between CPGs.

Results: Nine CPGs including recommendations on neuropathic pain could be selected and were assessed. In total, they used 149 references of which 72 (48%) were about cancer conditions, 39 (26%) about neuropathic pain, and only 3 about neuropathic pain in patients with cancer (2%). Only 28 (19%) references were shared between 2 or more guidelines. There was only one shared reference specifically related to cancer neuropathic pain. Recommendations and their evidence grading strongly differ between CPGs.

Conclusion: This work demonstrates an important heterogeneity between European recommendations on diagnosis and assessment of neuropathic pain in patients with cancer. The main weaknesses are the low level of evidence and the absence of specific data focusing on neuropathic pain in patients with cancer. We recommend that physicians dealing with neuropathic pain in patients with cancer should be specially trained, that a specific methodology to develop CPGs should followed, and that specific research should be developed on the diagnosis of neuropathic pain in patients with cancer.