Can Estrogen Receptor, Progesterone Receptor, and Proliferative Index be Considered as Isolated Prognostic Factors of Overall Survival in Early luminal Breast Cancer?

Abstract

BACKGROUND: There are a number of proven molecular and pathological markers important for the prognosis for OS of early luminal type breast cancer, but there are still some deficiencies mainly due to the non-linear relationship between the markers and the outcome of the disease. METHODS AND PATIENTS: In this retro-prospective study, clinical and pathological data were provided from 336 patients with breast cancer who underwent breast surgery and treatment between January 2010 and December 2013, and followed until December 2018. The aim of the study was an evaluation of ER, PR, and Ki-67 as independent prognostic factors for OS of early luminal breast cancer. RESULTS: Early luminal breast cancers were not predictive of ER expression status (p = 0.699, p = 0.356), whereas only early Luminal B was predictive for PR expression (>10%: 72.2%). Ki-67 in most of the cases of early Luminal B was with expression of >14–20% (p = 0.056). Patients with ER of 1–10% survived over 80 months (p = 0.0020) in early Luminal A, but ER expression status did not show prognostic significance for OS of early Luminal B (p = 0.775). PR status did not show prognostic significance for OS in early luminal types (p = 0.257, p = 0.622). ER >1%/PR >1% was protective in early Luminal B (p = 0.00043), but not in early Luminal A. CONCLUSION: Our results suggest ER, but not PR as independent prognostic factor for OS but only of early Luminal A. We did not prove Ki-67 as independent prognostic factor for OS of highly proliferative early breast cancer.