Utility of intercostal artery perforator flap in granulomatous lobular mastitis: a single-center retrospective study.

BACKGROUND: Determining a procedure to fill operation defects, maintain breast shape, and conceal surgical incisions remains a challenge for breast surgeons in treating granulomatous lobular mastitis (GLM). The intercostal artery perforator (ICAP) flap is a volume replacement technique in breast-conserving surgery. This study aimed to describe the feasibility, safety, and patient-reported outcomes of extended mass resection and breast defect reconstruction with an ICAP flap in selected GLM patients. METHODS: We retrospectively analyzed the data of 108 GLM patients treated surgically between January 2022 and May 2024 at our center. Patients were divided into three groups according to the actual surgical strategy received in routine clinical practice. The no reconstruction group was considered the main clinical comparator for the flap reconstruction group, whereas the no resection group was retained as an exploratory real-world reference group. RESULTS: A total of 43 patients underwent extended mass resection and defect reconstruction with an ICAP flap (flap reconstruction group), 37 patients underwent extended mass resection without breast defect reconstruction (no reconstruction group), and 28 patients continued with abscess drainage or fistula removal without mass resection (no resection group). The flap reconstruction group showed longer surgery times and drainage removal times, as well as more blood loss and drainage volumes, than the other groups (P<0.001). There were no significant differences in postoperative complications among the three groups (P>0.05). Compared with the no reconstruction group, the flap reconstruction group showed better patient-reported cosmetic change and higher satisfaction scores (P<0.001). No recurrence was observed in the flap reconstruction group during 1-year follow-up; however, this exploratory finding should be interpreted cautiously. CONCLUSIONS: Extended mass resection and breast defect reconstruction with an ICAP flap appears to be a feasible and safe option for selected GLM patients requiring resection, with potential advantages in maintaining breast appearance and improving patient-reported satisfaction. The observed recurrence difference should be interpreted cautiously because of the retrospective design, limited sample size, and short follow-up.