Objective: The objective of this study was to analyze the pain characteristics and factors influencing the outcome of pain control in patients with lung cancer having pain.
Methods: Pain characteristics, the effectiveness, and prognostic factors for pain control were analyzed in 152 patients with lung cancer having moderate or severe chronic pain admitted to Cancer Center of The First Hospital of Jilin University, People's Republic of China, between January 2012 and May 2013. Information about sex, age, pathological type, TNM stage, presence/absence of bone metastases, characteristics of pain, methods, and effectiveness of pain management was recorded.
Results: Patients with non-small-cell lung cancer and small-cell carcinoma accounted for 132/152 (86.8%) and 20/152 (13.2%) cases, respectively. Among them, moderate (72.4%) or severe pain (27.6%) was reported in 73.7% of the cases at stage IV, chest or back pain was reported in 76.3% of the cases, and pain in other locations in the rest of the cases. Bone metastases were apparent in 44.1% of the patients. Neuropathic pain was noted in 46.7% of the patients, and frequent breakthrough pain was noted in 25.7% of the patients. High pain intensity was associated with frequent breakthrough pain. Pain was adequately controlled in 81.6% of the patients prescribed 3 days of analgesics. More patients reported a KPS higher than or equal to 80 after 3 days of analgesic treatment (P<0.001). Severe pain, frequent breakthrough pain, and presence of bone metastases were independent risk factors for poor pain control. Severe pain, frequent breakthrough pain, or neuropathic pain in the patients using opioids required higher doses of analgesic for pain control. Opioids plus nonsteroidal anti-inflammatory drugs offered better pain control than opioids alone.
Conclusion: High pain intensity is associated with frequent breakthrough pain in patients with lung cancer, which can be largely controlled with analgesics. Severe pain, frequent breakthrough pain, presence of bone metastases, and neuropathic pain are predictors of refractory pain.
Keywords: analgesic effects; chronic pain; lung cancer; pain intensity.