Prognostic Factors, Treatment, and Outcomes in Early Stage, Invasive Papillary Breast Cancer: A SEER Investigation of Less Aggressive Treatment in a Favorable Histology.

Abstract

Invasive papillary breast cancer (IPBCA) represents 0.5% of invasive BCA, and is thought to carry a favorable prognosis. This population-based study reports on prognostic factors, treatment, and outcomes of early-stage IPBCA to explore whether there is any evidence to support less aggressive treatment. IPBCA cases from 1990 to 2009 of the recent Surveillance, Epidemiology, and End Results were analyzed. Inclusion criteria included patients with stage T1-2, N0 IPBCA. Univariate and multivariate analyses were performed using the variables of treatment, stage, race, hormone receptor status, grade (G1-3), and age. Treatment modalities included lumpectomy alone (LA), lumpectomy with radiation treatment (LRT), and mastectomy alone (MA). Among 10,485 patients, median follow-up was 56 months. Five and 10-year overall survival (OS) were 93.1% and 76.8%, respectively. Patients treated with LRT had superior mean OS 16.8 versus 14.9 years for MA (P=0.0004) and 14.2 years for LA (P=0.0003). Improved OS also correlated with lower histologic grade (P<0.0001), lower T-stage (P<0.0001), and younger age (P<0.0001). Black patients had the worst OS (12.7 y, P<0.0001). LRT is associated with superior OS for early-stage invasive papillary BCA patients, when compared with LA or MA in this population-based study. The findings support the standard of care breast conservation approach for patients with invasive papillary BCA. Other prognostic factors associated with worse OS include increased age, higher T-stage, higher histologic grade, and black race.