Do older patients with T1a lesions require sentinel lymph node biopsy?

Abstract

587 Background: Some have suggested that selected older women with T1a lesions may not require sentinel lymph node biopsy, or advocate forgoing axillary staging for older patients with clinically negative axillae. Methods: An IRB-approved database was queried for all patients undergoing SLNB for invasive breast cancer from 2000 to 2006. We compared 3 cohorts: premenopausal women ≤ 40 years old (PRE), perimenopausal women 40-55 years old (PERI), and postmenopausal women ≥ 55 years old (POST). Logistic regression and chi-square test were used. Results: The procedure was successful in 123/127 (97%), 556/559 (99%), and 569/582 (98%) of 1,268 PRE, PERI, and POST patients undergoing SLNB, respectively. POST patients had lower grade tumors than PERI and PRE (grade 1: 26% vs. 20% and 7%; grade 2: 48% vs. 43% and 48%; grade 3: 19% vs. 29% and 40%, p ≤ 0.01) and higher ER expression (ER+: 79% vs. 66% and 59%, p ≤ 0.01). PRE patients had a higher proportion of multifocal disease than PERI or POST (21% vs. 14% and 11%, p < 0.01) and more lymphovascular invasion than POST (20% vs. 12%, p < 0.01). A positive sentinel lymph node (PSLN) was found in 32% of PRE, 28% of PERI and 19% of POST patients (p < 0.01). Upon multivariable analysis, clinical stage, ER status, and lymphovascular invasion were significantly associated with PSLN, but age cohort no longer was (p = 0.28). In the T1a subset PRE, PERI, and POST patients were similar for the proportion of PSLN (p = 0.12). Conclusions: Despite more favorable pathology, there wasno significant association between PSLN and POST vs. PERI or PRE patients, when adjusting for other important factors. There should be no difference in the criteria for axillary staging between younger vs. older breast cancer patients. Given recent reports that older breast cancer patients are less likely to receive standard treatment for breast cancer and their prognosis may worsen as a result, these results underscore the importance of appropriate, aggressive staging of the older breast cancer patient. No significant financial relationships to disclose.