Background: 

Pain is a common symptom in patients with advanced, metastatic, or terminal cancer. Neuropathic pain and psycho-emotional suffering are factors that increase the difficulty of pain management. Pain control in patients with cancer remains a challenge for medical professionals.

Study Question: 

What is the evolution of neuropathic/mixed pain compared with nociceptive pain under standardized treatment in patients with cancer?

Study Design: 

A prospective, longitudinal, open-label, nonrandomized study was conducted on patients with cancer pain.

Measures and Outcomes: 

Pain type was assessed at admission using the modified Brief Pain Inventory, and pain intensity was assessed daily using the Numerical Rating Scale for 14 days and on days 21 and 28. Screening of depression was performed on days 1, 7, 14, 21, and 28 using the Hamilton Depression Rating Scale. Patients with pain and depression received analgesics with antidepressants, while patients without depression received analgesics or analgesics with an anticonvulsant depending on the pain subtype.

Results: 

Of 72 patients, 23 had nociceptive pain and 49 had neuropathic/mixed pain. At admission, pain intensity was higher for patients with neuropathic/mixed pain compared with nociceptive pain (mean values: 7.06 vs. 5.82) with statistical significance (P = 0.001) and remained as such at the end of this study (mean values: 3.77 vs. 2.73). A decrease in the mean pain intensity was observed in all types of pain, but without statistical significance regardless of pain type and treatment protocol used (P = 0.77). If depression was present, antidepressants combined with analgesics decreased pain and depression scores significantly (P = 0.001).

Conclusions: 

Patients with neuropathic/mixed pain have higher levels of pain and lower response to treatment. Identifying psycho-emotional suffering can improve pain control by intervening in the physical and psycho-emotional components of pain.