Introduction

Hormone receptor expression in breast cancer carries a strong prognostic value and also predicts response to hormonal therapy in these patients. The value of progesterone receptor (PR) status independent of the estrogen receptor (ER) status has remained unproven with conflicting reports. This study aimed at identifying any independent prognostic value associated with PR expression in Luminal–A, or Luminal–B type operable invasive breast cancer.

Material and methods

Retrospective analysis of the prospectively maintained data was done for patients who presented to our institution with invasive breast cancer and underwent curative surgery between 2002–2006. All patients found to have ER positivity were included in the study. Data on PR expression pattern was assessed using multivariate analysis for prognosis with respect to disease free survival (DFS).

 Results

Total 1256 patients underwent curative surgery for invasive breast cancer over a period of 5 years (2002– 2006). Of the total 854 patients included in the analysis, 596 had positivity for both ER and PR, isolated ER positivity was found in 246 patients, while only 12 patients were found to be PR positive in the absence of ER positivity. HER2 positivity was noted in 175 of these patients. A significant trend was seen towards improved outcomes in PR positive patients with respect to DFS at 10 years (p value–0.01). This survival benefit was maintained even in the presence of lymph node metastases, and in patients treated with or without chemotherapy. This benefit, however, was not seen in patients with high grade (modified Bloom Richardson grade 3) tumors (p value–0.4).

Conclusion

PR expression in hormone receptor positive operable IBC was found to be an important variable of prognosis, independent of the ER expression status. And, its presence was associated with an improved DFS in hormone receptor receptor positive operable IBC.