Anticipated Resection Ratio (ARR) Based Flap Selection for Volume‐Replacement Oncoplastic Breast‐Conserving Surgery: 130 Breast Cancer Patients Cohort From a South Asian Tertiary Cancer Center

Abstract

BACKGROUND: Volume-replacement oncoplastic breast-conserving surgery (VR-OBCS) reconstructs the lumpectomy cavity with autologous tissue and spares the contralateral breast. Chest-wall perforator flaps (CWPFs)-lateral, anterior, and medial intercostal artery perforator (LICAP, AICAP, MICAP) flaps-together with a pedicled latissimus dorsi (LD) flap form the usual toolkit, but most programs depend on hand-held color Doppler for perforator mapping and indocyanine-green (ICG) angiography for perfusion assessment, neither of which is widely available in resource-limited oncology units. We evaluated whether a structured radiological assessment using ARR, BEV, and aORV could facilitate preoperative planning for volume replacement oncoplastic breast-conserving surgery (VR-OBCS). METHODS: Consecutive women undergoing VR-OBCS at an Indian tertiary cancer center (January 2023-March 2025) were reviewed retrospectively. Eligibility required an anticipated resection ratio (ARR) ≥ 0.15 or expected poor cosmesis after standard BCS; an ARR of 0.20-0.40 was the usual planning range for perforator-based volume replacement. Flap choice followed a quadrant-based map; the pedicled LD flap was reserved for defined indications. Perforator zones were identified by intercostal-space counting; color Doppler and ICG were never used. The primary endpoint was primary R0 resection (SSO-ASTRO 2014 "no ink on tumor"); secondary endpoints included flap loss, Clavien-Dindo morbidity, oncological events, and 12-month BREAST-Q satisfaction. RESULTS: One hundred thirty women (mean age 47.7 ± 5.5 years) were treated: LICAP in 68 (52.3%), MICAP in 29 (22.3%), AICAP in 21 (16.2%), and pedicled LD in 12 (9.2%); 42.3% received neoadjuvant chemotherapy. Primary R0 was 95.4%, with all six margin-positive women achieving R0 at re-excision (final R0 100%). No total or partial flap loss occurred. Thirty-day morbidity was 25.4% (maximum Clavien-Dindo IIIa) and late morbidity 16.9%. At a median follow-up of 15.9 months (IQR 12.3-22.6), no locoregional or distant recurrence and no disease-related death were recorded. The median BREAST-Q Satisfaction-with-Breasts score was 86 (IQR 78-92); none preferred mastectomy. CONCLUSIONS: Simple preoperative calculation of BEV, aORV, and ARR can guide selection between standard or type I oncoplastic BCS, perforator-flap volume replacement, and muscle-based reconstruction. This approach achieved reliable margin clearance, preserved flap viability, and high patient satisfaction without Doppler or ICG, making it a practical planning tool for resource-limited centers.