Pain phenotypes in American breast cancer survivors: analysis of clinical, demographic and psychosocial factors

Abstract

Persistent Post-Mastectomy Pain (PPMP), the incidence of which international reports estimate at 15-58%, is increasingly recognized as a major individual and public health problem. The etiology of PPMP is likely multifactorial, may be partially neuropathic in nature, and results in considerable disability and psychological distress. Previous reports, though somewhat discrepant, indicate risk factors for PPMP may include younger age, surgical extent, axillary dissection, reconstruction, previous pain, radiation and chemotherapy. In the current study, we investigated the incidence, character, and psychosocial correlates of PPMP in 611 women receiving mastectomy and adjuvant treatment (chemotherapy, radiation, hormone therapy). Pain location, intensity, magnitude and burden were assessed using a breast cancer pain questionaire1 and other established pain assessment tools 3.20+/-2.95 years postoperatively. Nearly half (47.4%) reported pain associated with previous mastectomy, with 32.5% reporting clinically significant (>3/10) pain, and 2.9% rating pain severe (>8/10). Of those with clinically significant pain, 29% reported daily occurrence. Pain locations included breast(74%), axilla(45%), side(20%), or arm(20%). Incidence of pain did not vary according to time since surgery after 6 months. Higher pain scores correlated significantly with neuropathic quality of pain(R=0.62,p<0.05). Multifactorial analysis of psychosocial correlates showed a strong association between clinically significant pain and Pain Catastrophizing Scale(R=0.43,p<0.05) and somatization(R=0.21,p<0.05), as assessed by the Brief Symptoms Inventory-18. Anxiety(R=0.19,p<0.05), depression(R=0.18 ,p<0.05) and sleep disturbance(R=0.18 ,p<0.05) scores were also positively correlated with pain. Improved characterization of PPMP and the psychosocial landscape in which it occurs may allow prospective identification of patients at risk, and allow targeting of preventive measures in the perioperative period. (1. Gartner, JAMA, 2009.)