Recent Advances in Prostate Cancer Treatment

Effectiveness of Combination Therapy

Recent clinical trials have demonstrated that the combination of abiraterone and androgen-deprivation therapy (ADT) significantly enhances the survival rate for patients with metastatic or locally advanced prostate cancer. This is particularly crucial as approximately one in seven men globally will be diagnosed with prostate cancer at least once in their lifetime.

Prevalence and Impact of Prostate Cancer

Prostate cancer, which affects the walnut-sized prostate gland in the male reproductive system, ranks as the third leading cause of death among men in Canada. Statistics reveal that, on average, 58 men are diagnosed daily, with 11 succumbing to the disease.

Role of Androgens in Prostate Cancer

Research indicates that androgens, including testosterone, are essential for the growth of prostate cancer cells. Consequently, many treatment strategies focus on androgen suppression, aiming to inhibit the production and effects of testosterone and other male hormones.

Details of the STAMPEDE Trial

A pivotal clinical trial, known as the Systemic Therapy in Advancing or Metastatic Prostate Cancer: Evaluation of Drug Efficacy (STAMPEDE), led by Parmar, Snydes, and colleagues, explored the efficacy of a new combination therapy. The findings were published in The New England Journal of Medicine.

This trial involved 1,917 patients diagnosed with either metastatic or high-risk locally advanced prostate cancer, including those who had previously undergone radical surgery or radiotherapy and were experiencing relapses. Participants were randomly assigned to receive either the combination therapy of abiraterone and ADT or ADT alone, in a 1:1 ratio.

Trial Outcomes and Survival Rates

The average age of participants was 67 years, with an average follow-up duration of 40 months. The primary outcome assessed was overall survival, defined as the duration from randomization to death from any cause.

In the group receiving combination therapy, 184 deaths were recorded, alongside 248 cases of treatment failure. In contrast, the ADT-only group experienced 262 deaths and 535 treatment failures. The results indicated a 71% relative improvement in time to treatment failure with the use of abiraterone combined with ADT, translating to a 37% difference in overall survival rates.

Notably, the majority of deaths occurred among patients with metastatic disease, yet the findings were consistent across both metastatic and non-metastatic prostate cancer patients.

Conclusion

These promising results underscore the potential of the abiraterone and ADT combination therapy, offering increased overall and failure-free survival rates for men diagnosed with metastatic or locally advanced prostate cancer compared to those receiving only ADT.

References

James ND, de Bono JS, Spears MR, Clarke NW, Mason MD, Dearnaley DP, Ritchie AWS, Amos CL, Gilson C, Jones RJ, Matheson D, Millman R, Attard G, Chowdhury S, Cross WR, Gillessen S, Parker CC, Russell JM, Berthold DR, Brawley C, Adab F, Aung S, Birtle AJ, Bowen J, Brock S, Chakraborti P, Ferguson C, Gale J, Gray E, Hingorani M, Hoskin PJ, Lester JF, Malik ZI, McKinna F, McPhail N, Money-Kyrle J, O’Sullivan J, Parikh O, Protheroe A, Robinson A, Srihari NN, Thomas C, Wagstaff J, Wylie J, Zarkar A, Parmar MKB, Sydes MR; STAMPEDE Investigators. Abiraterone for Prostate Cancer Not Previously Treated with Hormone Therapy. N Engl J Med. 2017 Jul 27; 377(4):338-351. doi: 10.1056/NEJMoa1702900. Prostate Cancer Statistics. Canadian Cancer Society Website http://www.cancer.ca/en/cancer-information/cancer-type/prostate/statistics/?region=sk. Accessed August 7th, 2017.