Although there is a huge body of scientific research on cancer biology, the quality and quantity of research on the management of cancer pain lags far behind, according to researchers at the New England Medical Center Evidence-based Practice Center (EPC) conducting a systematic literature review for the Agency for Healthcare Research and Quality (AHRQ). Overall, EPC found that the solid evidence that exists on specific therapies such as anti-inflammatory drugs or opioids is overshadowed by inadequate guidance on more complex choices now expected of front-line clinicians.

In particular, the EPC found little research on quality of life in relation to pain control, drug interactions during long-term cancer pain treatment, the optimal sequence of adding drugs to improve pain control, how best to combine drug with non-drug therapies, and the impact that ethnicity has on cancer pain and patients' responses to treatment. Also, it found almost no analgesic drug trials in children with cancer pain. 

Cancer pain affects the quality of life of large numbers of patients and their families, and adds substantially to the already considerable national disease burden of cancer. Still, vulnerable populations—minorities, women, children, and the elderly—continue to be at increased risk of being underassessed and undertreated for pain.