Risk of local failure in breast cancer patients with lobular carcinoma in situ at the final surgical margins: is re-excision necessary?
OBJECTIVE
To compare the outcome of patients with invasive breast cancer both with and without lobular carcinoma in situ (LCIS)-positive/close surgical margins after breast-conserving treatment.


METHODS
We retrospectively studied 2358 patients with T1-T2 invasive breast cancer treated with lumpectomy and radiation therapy from January 1980 to December 2009. Median age was 57 years (range, 24-91 years). There were 82 patients (3.5%) with positive/close LCIS margins (<0.2 cm) and 2232 patients (95.7%) with negative margins. A total of 1789 patients (76%) had negative lymph nodes. Patients who received neoadjuvant chemotherapy were excluded. A total of 1783 patients (76%) received adjuvant systemic therapy. Multivariable analysis (MVA) was performed using Cox's proportional hazards model.


RESULTS
The 5-year cumulative incidence of locoregional recurrence (LRR) was 3.2% (95% confidence interval [CI] 2.5%-4.1%) for the 2232 patients with LCIS-negative surgical margins (median follow-up 104 months) and 2.8% (95% CI 0.7%-10.8%) for the 82 patients with LCIS-positive/close surgical margins (median follow-up 90 months). This was not statistically significant (P=.5). On MVA, LCIS-positive margins after the final surgery were not associated with increased risk of LRR (hazard ratio [HR] 3.4, 95% CI 0.5-24.5, P=.2). Statistically significant prognostic variables on Cox's MVA for risk of LRR included systemic therapy (HR 0.5, 95% CI 0.33-0.75, P=.001), number of positive lymph nodes (HR 1.11, 95% CI 1.05-1.18, P=.001), menopausal status (HR 0.96, 95% CI 0.95-0.98, P=.001), and histopathologic grade (grade 3 vs grade 1/2) (HR 2.6, 95% CI 1.4-4.7, P=.003).


CONCLUSIONS
Our results suggest that the presence of LCIS at the surgical margin after lumpectomy does not increase the risk of LRR or the final outcome. These findings suggest that re-excision or mastectomy in patients with LCIS-positive/close final surgical margins is unnecessary.
Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts.
Betro T
BT
Sadek
Mina N
MN
Shenouda
Rita F
RF
Abi Raad
Andrzej
A
Niemierko
Amany R
AR
Keruakous
Saveli I
SI
Goldberg
Alphonse G
AG
Taghian
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000473:pathology / Q000532:radiotherapy / Q000601:surgery*; D002278:Carcinoma in Situ / Q000473:pathology / Q000532:radiotherapy / Q000601:surgery*; D018275:Carcinoma, Lobular / Q000473:pathology / Q000532:radiotherapy / Q000601:surgery*; D005260:Female; D006801:Humans; D015412:Mastectomy, Segmental; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D018365:Neoplasm, Residual; D016016:Proportional Hazards Models; D011879:Radiotherapy Dosage; D012086:Reoperation; D012189:Retrospective Studies; D012306:Risk; D017211:Treatment Failure; D019564:Unnecessary Procedures; D055815:Young Adult