Men with low-grade prostate cancer have the same long-term outcomes when they are treated with a shorter radiation schedule, compared to those treated with a longer, conventional radiation schedule. These results were recently presented at the 2016 annual Genitourinary Cancers Symposium.
Low-grade prostate cancer refers to cancer that has not spread to distant sites in the body, and is slow-growing. This stage of prostate cancer does not require aggressive therapies to maintain disease control.
Depending upon several variables, including the overall health and age of the patient, different therapeutic approaches exist for low-grade prostate cancer, including radiation therapy.
Researchers continue to compare different therapeutic approaches in order to ultimately improve outcomes of these patients, while maintaining optimal quality of life.
The Radiation Therapy Oncology Group (RTOG) conducted a clinical trial to evaluate long-term outcomes among men with low-grade prostate cancer who were treated with a conventional radiation therapy, compared to those treated with hypofractionated radiation therapy.
Hypofractionated radiation therapy is the delivery of higher doses of radiation therapy per fraction (visit for radiation treatment) than conventional radiation therapy; however, the overall dose after the course is completed tends to be less. The length of the entire course of treatment is also significantly shorter than that of conventional radiation therapy.
The trial included 1,115 men with low-risk, early-stage prostate cancer who were treated with either conventional radiation therapy (41 fractions over 8.2 weeks) or hypofractionated radiation therapy (28 fractions over 5.6 weeks). Patients were treated between 2006 and 2009, and were followed for an average of nearly 6 years.
- The estimated 7-year cancer-free survival rates are 75.6% among men treated with conventional radiation, and 81.8% among those treated with hypofractionated radiation.
- Other outcomes, such as overall survival, time to biochemical relapse (elevation of PSA levels), and severe side effects were also similar between the two treatment groups.
The researchers concluded that among men with low-risk prostate cancer, a shorter course of radiation therapy utilizing a hypofractionated radiation schedule, provides similar outcomes compared to a longer course of conventional radiation therapy.
Reference: Lee W, Dignam J, Amin M, et al. NRG Oncology RTOG 0415: A randomized phase III non-inferiority study comparing two fractionation schedules in patients with low-risk prostate cancer. Proceedings from the 2016 annual genitourinary cancers symposium. Abstract #1.