Definitive radiotherapy for prostate cancer (PCa), even high-risk cases, is effective long-term, Australian researchers concluded.
After a median follow-up of 92 months (maximum 163.8 months), the 8-year overall survival rates and biochemical relapse-free survival rates among 1121 patients who underwent PCa radiotherapy were 78.4% and 68.1%, respectively, a team led by Jeremiah F. de Leon, MBBS, of the Illawarra Cancer Care Centre in Wollongong, New South Wales, reported online ahead of print in the Journal of Medical Imaging and Radiation Oncology. The median survival time for the entire cohort was 157.1 months. The median time to biochemical failure was 76 months.
The 8-year OS rates were 84.5%, 78.4%, and 68% among patients with low-, intermediate-, and high-risk disease, respectively. The biochemical relapse-free survival rates were 80.3%, 65.7%, and 53.7%, respectively.
“To our knowledge, this is the largest prospective cohort of Australian prostate cancer patients treated with radiotherapy,” the authors wrote, noting that their overall findings are consistent with those reported in the international literature.
Patients had a median age of 69.6 years (range 45 to 87 years). All patients were treated to a dose of 70 to 74 Gy. Patients were classified as having low-, intermediate-, and high-risk disease based on PSA level, clinical staging, and Gleason score. Intermediate-risk patients were treated with up to 6 months of androgen-deprivation therapy (ADT); high-risk patients were offered neoadjuvant and adjuvant ADT.
Overall, 61.6% of patients received either adjuvant or neoadjuvant ADT and the proportion varied by risk category, with 8.3%, 50.3%, and 96.2% of patients with low-, intermediate-, and high-risk disease receiving any hormonal therapy.
De Leon JF, Kneebone A, Gebski V, et al. Long-term outcomes in 1121 Australian prostate cancer patients treated with definitive radiotherapy. J Med Imaging Radiat Oncol. 2018; published online ahead of print.