Introduction Chronic postsurgical pain (CPSP) occurs in 20%–30% of patients who undergo total mastectomy (TM) performed under general anesthesia alone and significantly affects the quality of life. Pectoserratus and interpectoral plane block have been reportedly combined with general anesthesia to control immediate postoperative pain after TM. Our prospective cohort study aimed to evaluate the incidence of CPSP after TM when pectoserratus and interpectoral plane block were combined with general anesthesia.

Methods We recruited adult women scheduled to undergo TM for breast cancer. Patients planned for TM with flap surgery, those who underwent breast surgery in the past 5 years, or those presenting with residual chronic pain after prior breast surgery were excluded. After general anesthesia induction, an anesthesiologist performed pectoserratus and interpectoral plane block with a ropivacaine (3.75 mg/mL) and clonidine (3.75 µg/mL) in 40 mL of 0.9% sodium chloride. The primary endpoint was the occurrence of CPSP—defined as pain with a Numeric Rating Scale Score of ≥3, either at the breast surgical site and/or at axilla, without other identifiable causes—evaluated during a pain medicine consultation at 6 months post TM.

Results Overall, 43/164 study participants had CPSP (26.2%; 95% CI: 19.7 to 33.6); of these, 23 had neuropathic type of pain (53.5%), 19 had nociceptive (44.2%), and 1 had mixed (2.3%) type of pain.

Conclusion Although postoperative analgesia has significantly improved in the last decade, there is still need for improvement to reduce CPSP after oncologic breast surgery.

Trial registration number NCT03023007.