Clinicopathological Relevance and Prognostic Value of Androgen Receptor in Mammary Paget's Disease with Underlying Invasive Ductal Carcinoma.

INTRODUCTION

Mammary Paget's disease (MPD) is a rare cutaneous manifestation. Epidemiologically, more than half of the MPD patients concurrently have underlying invasive ductal carcinoma (MPD-IDC), and their prognosis remains poor despite multimodal treatments of breast cancer have markedly improved patients' survival. Accordingly, it is crucial to seek out novel therapeutic targets of MPD-IDC. As an emerging biological marker, the value of androgen receptor (AR) in MPD-IDC is inconsistent. Our objectives were to investigate the associations between AR and clinicopathological factors, and to explore its prognostic value in MPD-IDC.

METHODS

We retrospectively analyzed data from 103 MPD-IDC patients, and immunohistochemical staining was used to determine their AR statuses.

RESULTS

AR was expressed in 44 patients (42.7%), and AR expression was significantly correlated with body mass index (BMI) (p = 0.038) and axillary lymph node (ALN) status (p = 0.025). Kaplan-Meier curves showed that AR positivity was significantly associated with better overall survival (OS) in MPD-IDC patients (p = 0.019) and estrogen receptor-negative MPD-IDC patients (p = 0.039). Multivariate Cox regression analysis revealed that AR was not an independent prognostic indicator of disease-free survival (DFS) or OS in MPD-IDC patients (p = 0.395 and p = 0.073, respectively).

CONCLUSIONS

In contrast to AR-negative tumors, patients with AR-positive ones were more likely to have lower BMI, no ALN metastasis, and better OS. AR-targeted treatments for MPD-IDC may add to existing therapeutic approaches to improve their effectiveness.