Regenerative peripheral nerve interface (RPNI) was first developed in 2012 by Dr. Paul Cederna at the University of Michigan as a means for amputees to control their prothesis with their minds. In the decade that followed, it was found RPNI surgery not only provided amputees with neuroma (a growth made up nerve tissue) pain relief but could help prevent neuroma from developing as well.

This single center, randomized controlled, investigator-initiated study will look at whether the RPNI, a nerve burying procedure involving protecting sensory nerves with a small piece of the patient's pectoralis muscle, performed at the time of the standard mastectomy with immediate breast reconstruction surgery can prevent and/or reduce the risk for long-term nerve pain after breast cancer surgery (also called neuroma-related post-breast surgery pain syndrome (PBSPS)) versus the standard surgery alone (Control group). Symptoms of PBSPS include discomfort, numbness, tingling, and shooting pain in the chest and breast area. It is relatively common and may have many causes.

About 200 adult females (18-65 years old) who are scheduled to undergo mastectomy with immediate breast reconstruction surgery will be approached for this study. Those who agree and sign the informed consent form will be randomized in 1:1 fashion (50/50 chance) to either the RPNI group or the no RPNI (Control) group. Study participants will complete self-reported surveys (pre-surgery and at Months 1, 3, 6, and 12 post-surgery) designed to measure pain levels, quality of life, and function before and after surgery. Study participation will last approximately 12 months. Subjects will remain blinded to their assigned study arm until their study participation has concluded.

Inclusion Criteria:

1. Adult female 18 to 65 years of age.
2. Undergoing breast mastectomy with immediate reconstruction.
3. Able to provide informed consent and comply with study procedures.

Exclusion Criteria:

1. History of chronic pain syndrome unrelated to breast surgery.
2. Unwillingness or inability to comply with the study's follow-up requirements.
3. Cognitive impairment or language barriers preventing proper understanding of study procedures and assessments.
4. Participation in other interventional trials or treatments aimed at pain management that could confound study outcomes as determined by the PI.
5. Other medical or surgical contraindication to the involved procedure (RPNI) as determined by the PI.

Recruitment is limited to females as virtually all cases of breast cancer, and associated mastectomy and reconstruction procedures, are in women.

Those who agree and sign the informed consent form will be randomized in 1:1 fashion (50/50 chance) to either the RPNI group or the no RPNI (Control) group. Subjects will remain blinded to their assigned study arm until their study participation has concluded.