Association of Clinical and Pathologic Variables with Lumpectomy Surgical Margin Status after Preoperative Diagnosis or Excisional Biopsy of Invasive Breast Cancer

PurposeTo evaluate the impact of preoperative diagnosis in obtaining negative lumpectomy margins.Materials and MethodsFive hundred and thirty five patients who underwent breast conserving therapy for stage I/II cancer from 1971 to 1996 were included in this IRB-approved retrospective analysis. Three hundred and ninety five patients had a defined inked margin status after initial excision. The following factors were evaluated for correlation with margins at initial excision: age (< or >45), grade (3/1 or 2), family history (present/absent), histology (lobular/other), estrogen receptor (ER) status, presence of extensive intraductal carcinoma (EIC), presence of lymphovascular invasion (LVI), and biopsy type (excisional/preoperative).ResultsBiopsy type (P < 0.0001), EIC (P = 0.002), ER status (P = 0.02), lobular histology (P = 0.02) and age (P = 0.02) were significantly correlated with initial margin status among the entire group. For patients who underwent preoperative diagnostic biopsy, 52% (35/67) had negative initial margins as compared to 29% (94/328) for excisional biopsy. Among patients who underwent preoperative biopsy, only lobular histology (P = 0.04) and LVI (P = 0.04) were related to initial margin status. The rate of re-excision was 34% for patients diagnosed preoperatively versus 61% with excisional biopsy (P < 0.0001). The percentage of patients with negative final margin status was similar with either core/needle or excisional biopsy (79 and 78%, respectively).ConclusionsPreoperative diagnosis is the most significant predictor of initial margin status in patients undergoing breast conservation. Patients with lobular histology may require improved preoperative and/or intraoperative assessment to increase the rate of negative margins at initial excision.