Prevalence of pain and relative diagnostic performance of screening tools for neuropathic pain in cancer patients: A cross‐sectional study

Abstract

Background: Neuropathic pain can be overlooked in cancer patients. The advent of screening tools can help in recognizing it. However, little is known about their relative diagnostic performance and factors that affect it. This study evaluated the prevalence of neuropathic pain using several diagnostic strategies in cancer patients undergoing chemotherapy. Methods: Patients attending the Oncology Unit of the investigators' site to continue their chemotherapy schedule were systematically screened for this cross-sectional study. Before starting chemotherapy drugs, pain specialists made a clinical diagnosis of neuropathic pain (either disease related, treatment related or comorbid) and medical oncologists administered three validated screening tools. Their relative diagnostic performance and the impact of some pain features on it were analysed using multivariate statistical methods. Results: From a total of 358 patients, 194 (54.2%) suffered from pain and 73 (20.4%) had a clinical diagnosis of pure neuropathic or mixed pain. Among the screening tools, the Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) was more specific (93.4%), although less sensitive (68.1%) than the Douleur Neuropathique in 4 Questions (DN4) (sensitivity: 87.5%, specificity: 88.4%). Interestingly, the specificities of these two instruments did not differ in patients with mild pain, while the DN4 remained to be more sensitive than the LANSS regardless of pain severity. Conclusions: Neuropathic pain is common in cancer patients undergoing chemotherapy. The DN4 might be of great help for the early detection of patients at risk because of incipient chemotherapy-related neuropathies and the LANSS to rule out neuropathic pain in patients with complex pain conditions.

Patient‐reported neuropathic pain in adolescent and young adult cancer patients

“…The developer of the painDETECT endorses use down to age 14 years. A comparison between several neuropathic pain screening tools in adults with cancer found the painDETECT to have a poorer sensitivity (but comparable specificity), when compared with other standard screening tools . However, to our knowledge, the additional neuropathic pain screening tools evaluated have not been used in adolescents.…”

“…A study in adult cancer patients referred for palliative radiotherapy for bone metastases found that only 12.5% of patients identified to have neuropathic pain on a screening tool were receiving neuropathic pain medications . A cross‐sectional study of adult cancer patients treated with chemotherapy reported that 56% of those found to have neuropathic pain by focused clinical examination and questioning were not receiving any analgesic medication . Published guidelines on neuropathic pain assessment see value in the use of screening tools to identify patients with possible neuropathic pain .…”

“…The painDETECT is reported to have an 85% sensitivity, 80% specificity, and 83% positive predictive value for differentiating neuropathic from nonneuropathic pain . The painDETECT has been used to identify a neuropathic pain phenotype in adults with low back pain, osteoarthritis, diabetic neuropathy, postherpetic neuralgia, postthoracic surgery, sickle cell disease, and cancer . The painDETECT has been utilized down to age 14 years and is approved for use down to age 14 per the developer (personal communication).…”

Detection of Neuropathic Pain in End‐Stage Cancer Patients: Diagnostic Accuracy of Two Questionnaires

“…Their clinical validation record is not comparable. Thus, the DN4 validation study has been tested in a few studies in cancer patients . Garcia del Paredes et al, in a Spanish population, found that only half of the cancer patients with neuropathic pain (diagnosed by clinicians) were actually detected by the DN4 questionnaire, while Perez et al found much better sensitivity and specificity values (87.5% and 88.4%, respectively) in a similar population of the same ethnicity.…”

State of the evidence

“…The ladder identifies opioids as the principal drug for moderate to severe pain with additional nonopioids and adjuvants introduced as needed (World Health Organization, n.d.). Approved add‐on therapies may include nonsteroidal anti‐inflammatories (NSAIDs), corticosteroids, anticonvulsants, and antidepressants (Perez et al., ). Unfortunately, these drugs are not without side effects and despite following this regimen, a minority of patients, 10%–20%, will still experience significant pain (Benyamin et al., ; WHO, n.d.).…”