Abstract
>276,000 Americans will be diagnosed with invasive breast cancer, lobular carcinoma in situ, or ductal carcinoma in situ this year and most will undergo breast surgery as part of their care. Although prognosis is excellent, many patients experience persistent post-surgical pain (PSP), which has no satisfactory pharmacological treatment. The causal contributions of pain-associated psychological factors (e.g., catastrophic thoughts about pain, psychological flexibility, self-efficacy) to the continuing burden of PSP have not yet been determined and may be opportune intervention targets. The randomized trial described here will compare the benefits of three manualized behavioral interventions for individuals with PSP. Participants will receive either: 1) self-guided health education (SGHE); 2) interventionist-guided health education (IGHE); or 3) interventionist-guided pain coping skills training with elements of acceptance and commitment therapy that specially target catastrophic thoughts about pain, self-efficacy, and psychological flexibility (CST-PSP). Participants will prospectively complete validated assessments of primary outcomes (PSP severity and interference) at baseline (pre-intervention) and 3-, 6-, and 12-months later. Validated measures of emotional distress and cancer-specific distress will be assessed as secondary outcomes. To test their roles as drivers of PSP, catastrophic thoughts about pain, self-efficacy, and psychological flexibility, will be assessed and statistically analyzed as mediators of hypothesized beneficial effects. The interventions' impacts on pain sensitivity and central sensitization will be investigated to test these physiological pathways as proximal drivers of PSP. To better characterize the patient experience, additional validated measures will be explored for associations with PSP, along with demographic and clinical factors. Trial registration: https://clinicaltrials.gov/ct2/show/NCT04225585, registered January 13, 2020.