According to results recently published in the International Journal of Radiation Oncology Biology Physics, 3 months of androgen suppression prior to radiation therapy appears to be just as effective as an 8-month course in patients with localized prostate cancer. However, longer follow-up may reveal differences between the two treatment courses, particularly in patients who are at a high risk of experiencing a cancer relapse.

Prostate cancer is the most commonly diagnosed cancer in men in the United States. The prostate is a walnut-sized gland that is located between the bladder and rectum and is responsible for forming components in semen. Localized, or early prostate cancer, refers to cancer that has not spread from the prostate to distant sites in the body. There is no definitive standard treatment option for patients with localized prostate cancer, with therapeutic options largely dependent upon the side effect profiles for each particular patient. Treatment may include surgery, radiation therapy, chemotherapy, or watchful waiting.

Hormone therapy, also referred to as androgen suppression therapy, is also a type of therapy that appears to be entering clinical management earlier in the course of the disease; however, patients with very advanced disease are also often treated with hormone therapy. Since prostate cancer is stimulated to grow from male hormones, hormone therapy consists of treatment that is used to reduce the levels of male hormones, particularly testosterone, in the body. Physicians are now evaluating the use of hormone therapy prior to the use of other therapies, referred to as neoadjuvant therapy, in early prostate cancer. Neoadjuvant therapy is used to shrink the cancer prior to treatment with another modality, so that treatment such as surgery or radiation therapy may ultimately be more effective in eradicating more of the cancer. However, optimal timing and sequencing of hormone therapy and radiation therapy in localized prostate cancer is still under investigation.

Researchers from Canada recently conducted a clinical trial evaluating neoadjuvant androgen suppression therapy prior to radiation in patients with localized prostate cancer. This trial included 378 patients who were treated with either 3 months of neoadjuvant androgen suppression therapy or 8 months of androgen suppression therapy prior to radiation therapy. At 5 years, the rate of cancer recurrences were similar between the two groups of patients, with cancer recurring at distant sites in the body in 3.4% of patients treated with 3 months of neoadjuvant androgen suppression, compared with 4.4% of patients treated with 8 months of neoadjuvant androgen suppression. However, patients considered to be at a high risk of developing a cancer recurrence had a cancer-free survival rate of nearly 40% in those treated with the 3-month regimen, compared to 52% in those treated with the 8-month regimen.

The researchers concluded that 3 months of neoadjuvant androgen suppression appears just as beneficial as 8 months of neoadjuvant androgen suppression prior to radiation therapy for localized prostate cancer. However, there appeared to be a trend toward improved cancer-free survival at 8 years in patients who were considered to be at a high risk of developing a cancer recurrence and were treated with the 8-month neoadjuvant regimen, compared to the 3-month regimen. Results from future clinical trials will help address the questions still surrounding treatment timing and sequence for patients with early stage prostate cancer. Patients with early prostate cancer who are to undergo androgen suppression may wish to speak with their physician about their individual risks and benefits of neoajuvant treatment regimens or the participation in a clinical trial evaluating other novel therapeutic approaches. Two sources of information regarding ongoing clnical trials include the National Cancer Institute (cancer.gov) and www.cancerconsultants.com. Personalized clinical trial searches are also performed on behalf of patients at cancerconsultants.com.

Reference: Crook J, Ludgate C, Malone S, et al. Report of a multicenter Canadian phase III randomized trial of 3 months vs. 8 months neoadjuvant androgen deprivation before standard-dose radiotherapy for clinically localized prostate cancer. International Journal of Radiation Oncology Biology Physics. 2004;60:15-23.

Copyright © 2018 CancerConnect. All Rights Reserved.