Utilization Trends of Novel Hormonal Agents in Metastatic Castration-Resistant Prostate Cancer in Quebec

Abstract

Background: The introduction of novel hormonal agents (NHAs) such as abiraterone acetate (ABI) and enzalutamide (ENZ) for metastatic castration-resistant prostate cancer (mCRPC) was an important milestone given their survival benefits, tolerability, and ease of administration relative to taxane chemotherapies. This descriptive study sought to describe the utilization trends of ABI and ENZ in patients with mCRPC in the early years after their approval in the province of Quebec in Canada. Methods: A retrospective population-based cohort was extracted from Quebec public healthcare administrative databases. The cohort included first-time users of NHAs (ABI or ENZ) from 2011 to 2016. The primary analyses aimed to describe the overall temporal trends (2011–2016) of NHA initiators by chemotherapy status (chemotherapy-naïve versus post-chemotherapy), and prescribing specialty (medical oncology versus urology versus others). Results: The cohort comprised 2183 patients, with 1562 (72%) in the chemotherapy-naïve group and 621 (28%) in the post-chemotherapy group. While the majority of patients were post-chemotherapy NHA initiators in 2012, this proportion decreased over time and accounted for only 13% of NHA initiators by the end of 2016. Medical oncologists were the most frequent prescribers of NHAs (upwards of 60%) throughout 2012 but fell to 45% by the end of 2016. Conversely, the proportion of prescriptions by urologists increased from 22% in 2012 to 42% in 2016. Conclusion: Over time, there was an increasing proportion of (1) patients who initiated NHAs without prior chemotherapy treatment, (2) NHA prescribing by urologists, and (3) ENZ users. Taken together, this implies that the introduction of NHAs has altered the management of mCRPC and urologists quickly adopted NHAs into their practice.

Androgen receptor and its correlation with estrogen and progesterone receptors, aimed for identification of cases for future anti-androgen therapy in endometrial cancers

“…Hormonal therapy targeting both ER and PR is effective in treatment of endometrial cancers when the receptors are expressed [ 15 , 25 ]. Overall, since metastatic-endometrial carcinomas and NEEC express AR, this may serve as a potential therapeutic target for these patients based on the historical targeted treatment of male prostate and female breast cancers with anti-androgen/AR agents [ 6 – 9 ]. Targeting AR has not been explored extensively in this disease model which could be a potential alternative hormonal anticancer therapy for ECs using androgen and/or AR antagonists [ 26 ].…”

“…anti-androgen/AR agents [6][7][8][9]. Targeting AR has not been explored extensively in this disease model which could be a potential alternative hormonal anticancer therapy for ECs using androgen and/or AR antagonists [26].…”

“…Progesterone can stop estrogen driven proliferation and can be used in the therapy for low grade endometrioid carcinomas [2]. Some of the non-gynecological neoplasms, such as prostate cancer which express androgen receptor (AR), have been treated with androgen antagonist for many years [6]. Also, AR-targeted treatment for triple negative breast cancers, including apocrine type breast carcinoma, has been an area of active investigation [7][8][9].…”