Factors related to re-excision procedures following primary breast-conserving surgery for women with breast cancer in the U.S. Military Health System.

Abstract

Re-excision surgery is undertaken to obtain clear margins after breast-conserving surgery (BCS) for localized breast cancer. This study examines patient and tumor characteristics related to re-excision surgery in the universal-access Military Health System (MHS). Retrospective analysis of patients with pathologically confirmed stage I-III breast cancer between 1998 and 2014 in the Department of Defense Central Cancer Registry and MHS Data Repository-linked databases who received primary BCS. Multivariable stepwise logistic regression methods identified characteristics associated with re-excision surgery (lumpectomy and mastectomy) and conversion to mastectomy, given as adjusted odds ratios (AOR) and 95% confidence intervals (CIs). Of 7637 women receiving BCS, 26.3% had a re-excision and 9.9% converted to mastectomy. Tumor location, larger tumor size (≥4 cm), and regional lymph node involvement were associated with a greater likelihood of re-excision and mastectomy conversion. Pathology before BCS (AOR, 0.39; 95% CI, 0.35, 0.44 for re-excision) and neoadjuvant treatment (AOR, 0.50; 95% CI, 0.36, 0.69 for re-excision) were associated with a decreased likelihood of these outcomes. Additionally, age, tumor histology, and military-specific variables were associated with mastectomy conversion. Comprehensive preoperative workup, including tumor pathology, may better inform surgical decision-making and reduce re-excision rates.