Persistent Pain After Breast Cancer Surgery

Abstract

Purpose of the study: To identify strengths and weaknesses in current studies with a view to carrying out a major multi-center study in Australia. Methods: The literature was reviewed using standard Medline and Ovid methods. Bibliography of well known key recent papers were used to identify further papers. Results: Studies evaluating persistent pain after breast cancer surgery have been small and few were prospective controlled studies with adequate power. Like Jung et al[1] we found that the literature was inconsistent in defining chronic pain and differentiating the breast cancer surgery pain syndromes. Marked variations in prior studies are due to differences in: study size (n = 22 to 282 patients), methodology, diagnostic criteria, pain assessment instruments, and distribution of demographic and clinical characteristics in the samples studied. Unfortunately the largest study to date, the ALMANAC Trial (n = 1031) which compared sentinel node biopsy vs “standard axillary dissection” evaluated arm and shoulder function and quality of life, but not pain[2]. From the current literature, it appears that neuropathic breast and arm pain are most common. Widely varying prevalence estimates of different neuropathic pain syndromes have been reported: phantom breast pain (3–44%); intercostobrachial neuralgia (ICBN) (16–39%); ICBN in breast conserving surgery (14–61%); and “neuroma pain” (23–49%). The most established risk factors for surgically related neuropathic pain syndromes are intraoperative nerve trauma, severe acute postoperative pain, and high use of postoperative analgesics[1]. Psychosocial distress is reported to be a risk factor and a consequence of chronic pain[1]. Conclusions: Well-designed large multi-center studies are required to identify prevalences of various pain types, associated risk factors and treatment success for pain after breast cancer surgery. Such a study is in progress through the collaboration of our group with the Sentinel Node vs Axillary Clearance (SNAC) Study of 1000 women following breast surgery, conducted by the Royal Australian College of Surgeons (RACS).