Evaluation of PSMA in HER2- AR+ Metastatic Breast Cancer

Summary

The purpose of this research is to determine the expression of prostate specific membrane antigen (PSMA) in human epidermal growth factor receptor 2 (HER2)-negative, androgen receptor (AR)-positive metastatic breast cancer, and to determine its role in resistance to the anti-androgen, bicalutamide. The investigators hypothesize that PSMA expression will correlate with resistance to anti-androgen therapies, as has been documented in prostate cancer, and this can be used to select patients most likely to benefit from these therapies in future clinical trials. 15 people with HER2-negative, AR-positive metastatic breast cancer will be enrolled and be on study for about 3 days.

Detailed Description

Primary Objective: * To evaluate the expression of PSMA via 18F-DCFPyL PSMA-based PET/CT in patients with metastatic HER2-negative, AR-positive breast cancer. Expression of PSMA will be quantified using PSMA-based PET imaging using a novel agent, 18F-DCFPyL, as a non-invasive imaging biomarker of tumor neovasculature in HER2-negative, AR-positive metastatic breast cancer. Secondary Objectives: * PSMA PET will be compared with the expression of PSMA in CTCs and diagnostic metastatic tissue from patients with HER2-negative, AR-positive metastatic breast cancer. * PSMA expression will be correlated with clinical benefit (objective response and progression-free survival) to bicalutamide and ribociclib for patients enrolled in NCT03090165.

Eligibility Criteria

Interventions