Delaying initiation of external beam radiation therapy (RT) for up to 6 months by using androgen deprivation (ADT) is both feasible and safe for patients with localized prostate cancer (PCa), a new study confirms.
Among men with unfavorable intermediate-risk PCa, the 10-year overall survival rates for men who initiated RT 0 to 60 days before ADT initiation, 1 to 60 days after ADT initiation, 61 to 120 days afterward, and 121 to 180 days afterward were 59.2%, 57.9%, 62.3%, and 58.9%, respectively. Among men with high-risk or very high-risk PCa, the 10-year overall survival rates were 58.9%, 51.7%, 54.8%, and 52.4%, respectively.
No significant overall survival differences were found for groups receiving RT after ADT compared with before in either the unfavorable intermediate-risk or high- to very-high risk cohorts, Vinayak Muralidhar, MD, MSc, of Brigham and Women’s Hospital in Boston, Massachusetts, and colleagues reported in JAMA Oncology. The team adjusted the multivariable Cox survival analyses for Gleason score, PSA, T stage, year of diagnosis, Charlson-Deyo comorbidity score, demographics, region, income, insurance status, and facility-related factors. ADT duration was unknown, however.
For the study, the investigators analyzed data from 63,858 men with localized PCa in identified using the National Cancer Database. Of these, 79.2% identified as White, 16.8% as Black, 2.2% as Asian, 0.2% as Native American, and 1.6% as other. The men had a mean age of 69.9 years. The unfavorable intermediate-risk PCa cohort comprised 19,258 men, including 4220 who died. The high- to very-high risk PCa cohort comprised 44,600, including 10,959 who died.
According to the investigators, the new findings have potential implications for patients undergoing RT during the COVID-19 pandemic, as daily hospital trips for RT increase the possibility of viral transmission.
“These results validate the findings of 2 prior randomized trials and possibly justify the delay of prostate RT for patients currently receiving ADT until COVID-19 infection rates in the community and hospitals are lower,” Dr Muralidhar’s team stated.
Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Dee EC, Mahal BA, Arega MA, et al. Relative timing of radiotherapy and androgen deprivation for prostate cancer and implications for treatment during the COVID-19 pandemic. JAMA Oncol. Published online August 13, 2020. doi:10.1001/jamaoncol.2020.3545