The proposed study will be a pilot randomized controlled trial comparing treatment as usual (TAU) to treatment as usual plus a brief Acceptance and Commitment Therapy (ACT) intervention (TAU + ACT) with mastectomy and lumpectomy patients identified as at-risk for developing persistent post-operative pain. The ACT intervention is a single individual therapy session scheduled two weeks following surgery. Potential participants will be recruited from the University of Iowa Breast Cancer Clinic. A sample size of n = 30 for each arm will be recruited. An attrition rate of 20% is anticipated so the total N to be recruited for the study is 72 participants. Study measures will consist of self-report questionnaires and medical record data. Data will be collected prior to surgery, one-week after surgery, and 3 months after surgery.

Psychological interventions addressing depression, anxiety, and psychological approaches to pain management in pre-surgical patients may serve to prevent the development of persistent post-surgical pain, depression, and anxiety in at-risk individuals. Acceptance and Commitment Therapy (ACT) is a psychological therapy that has been shown to be effective in minimizing the impairing impact of chronic pain and in treating depression and anxiety. ACT is a behavior therapy incorporating mindfulness, which aims to increase psychological flexibility via facilitating psychological acceptance and committed action in the direction of one's personally identified values. ACT has also shown promise in brief interventions, including a one day ACT workshop with patients with comorbid migraine and depression. The current study proposes to identify pre-operative breast cancer patients who are at increased risk for developing persistent post-surgical pain and to offer a brief ACT intervention with the aim of reducing the incidence of persistence post-surgical pain and psychological sequela.

Inclusion criteria: 1) ≥18 years of age, 2) scheduled for mastectomy or lumpectomy for breast cancer or DCIS, 3) identified to be "at risk" (per guidelines below).

At risk criteria: Psychological distress (elevated anxiety, depression, or pain catastrophizing), under the age of 50, or with a pre-existing chronic pain condition. Scores of 10 or above on the Generalized Anxiety Disorders 7-item scale or the Personal Health Questionnaire Depression 8 item Scale will indicate elevated anxiety or depression. A score of 30 or above on the Pain Catastrophizing Scale will indicate elevated catastrophizing.

Exclusion Criteria:

1) language or cognitive barriers preventing completion of questionnaires, 2) severe psychiatric disorder: bipolar or psychotic disorder, 3) significant surgical complications.