Large Study Confirms Radiation therapy not only destroys prostate cancer in patients with early disease but keeps it from returning, a very large study of patients from six medical centers has found.
The study confirms and elaborates on what has been reported before by individual medical centers: radiation therapy is an effective means to treat localized (stage T1B, T1C, or T2) tumors, said lead author William U. Shipley, MD, of Massachusetts General Hospital, Harvard Medical School, in Boston, Massachusetts.
The multicenter nature of this study shows that previous studies using smaller numbers of patients at individual medical centers can be widely generalized, said Anthony Zietman, md, also of Massachusetts General Hospital and Harvard Medical School.
Five-Year Follow-up Finds Patients Disease Free
All patients in the study received external-beam radiation therapy only and were followed after treatment with regular prostate-specific antigen (PSA) blood tests. The study found that 81% of patients who had a low pretreatment PSA level (less than 10 ng/mL) had no evidence of disease (ie, no consecutive rises in PSA levels) 5 years following radiation treatments. In addition, 68% of patients with a pretreatment PSA level higher than 10 ng/mL but lower than 20 ng/mL were disease free at 5-year follow-up.