Erector Spinae Plane versus Pectoralis Nerve Block for Mastectomy in Cancer Patients: A Retrospective, Multicenter Cohort Study

Edward N Yap; Julia Wei; Curtis Darling; Elizabeth Linehan; Matthias Behrends; Kevin P Ng

doi:10.2147/JPR.S538581

Erector Spinae Plane versus Pectoralis Nerve Block for Mastectomy in Cancer Patients: A Retrospective, Multicenter Cohort Study

J Pain Res. 2025 Sep 16:18:4775-4785. doi: 10.2147/JPR.S538581. eCollection 2025.

Authors

Edward N Yap^{1

2}, Julia Wei³, Curtis Darling⁴, Elizabeth Linehan⁵, Matthias Behrends², Kevin P Ng^{6

7}

Affiliations

¹ Department of Anesthesia, The Permanente Medical Group, Kaiser Permanente South San Francisco, South San Francisco, CA, USA.
² Department of Anesthesia and Perioperative Care, University of California San Francisco, San Francisco, CA, USA.
³ Division of Research, Kaiser Permanente Northern California, Oakland, CA, USA.
⁴ Department of Anesthesia, The Permanente Medical Group, Kaiser Permanente Santa Clara, Santa Clara, CA, USA.
⁵ Department of General Surgery, Division of Breast Surgical Oncology, the Permanente Medical Group, Kaiser Permanente San Francisco, San Francisco, CA, USA.
⁶ Department of Anesthesia, The Permanente Medical Group, Kaiser Permanente Walnut Creek, Walnut Creek, CA, USA.
⁷ Department of Anesthesiology & Perioperative Medicine, Drexel University College of Medicine, Philadelphia, PA, USA.

Abstract

Background: Mastectomy patients require effective acute postoperative pain management. Regional anesthesia techniques such as fascial plane blocks are important pain treatment modalities to address pain control. This study compared the effects of the erector spinae plane (ESP) block versus the pectoralis nerve (PECS) block in providing postoperative analgesia for mastectomy patients.

Methods: This retrospective study included 517 breast cancer patients undergoing mastectomy from 2017 to 2020, with 428 receiving a PECS block and 89 an ESP block. The primary outcome examined was total opioid use during hospital stay measured in morphine milligram equivalents (MME). Secondary outcomes included length of hospital stay, post-anesthesia care unit (PACU) pain scores, PACU postoperative nausea and vomiting (PONV), 30-day readmission rates, and development of postmastectomy pain within six months of surgery.

Results: No significant difference in median total opioid use between the ESP (53 MME (IQR: 38-80 MME)) and PECS (60 MME (IQR: 30-82.5 MME)) groups. Multivariable analysis confirmed no difference in total opioid consumption. There was no significant difference between the two groups in PACU average and maximum pain scores, PACU PONV, hospital length of stay, 30-day hospital readmission, and development of postmastectomy pain within six months of surgery.

Conclusion: Compared to the PECS block, the ESP block demonstrated no significant difference in acute pain outcomes and recovery in patients undergoing mastectomy for breast cancer, with similar hospital discharge times and long-term outcomes.

Keywords: breast cancer; erector spinae plane block; mastectomy; opioid consumption; pectoralis nerve block; postoperative analgesia; regional anesthesia.