Adding androgen deprivation therapy (ADT) to definitive radiation therapy (RT) and prolonging adjuvant ADT both increase metastasis-free survival in patients with intermediate- to high-risk prostate cancer, investigators confirm.
The MARCAP consortium conducted a systematic review and meta-analysis of 12 randomized trials involving 10,853 patients published during 1987-2010. Six trials examined ADT use with RT, 3 neoadjuvant ADT prolongation, and 4 adjuvant ADT prolongation.
Adding ADT to RT significantly improved metastasis-free survival (MFS) by 17%, compared with RT alone, Amar U. Kishan, of the University of California, Los Angeles, and colleagues reported in The Lancet Oncology. To prevent 1 distant metastasis event at 10 years, 8-18 patients would need to be treated with the dual regimen on the basis of National Comprehensive Cancer Network (NCCN) risk group, they stated.
Prolonging adjuvant ADT from 4-6 months to 18-36 months significantly improved MFS by 16%, the investigators further reported. To prevent 1 distant metastasis event, 10 patients with high-risk disease would need to be treated. Extending neoadjuvant ADT from 3-4 months to 6-9 months did not prolong MFS.
Benefits were similar regardless of radiation dose, patient age, and NCCN risk group, Dr Kishan’s team highlighted.
“We provide the strongest level of evidence for the routine recommendation for the addition of ADT to radiotherapy in men with intermediate-risk disease, and the use and prolonged adjuvant ADT for men with high-risk disease, irrespective of radiotherapy dose,” Dr Kishan and colleagues wrote. “However, the strategy of prolongation of neoadjuvant ADT should not be routinely recommended.”
Additional research is needed to optimize ADT use in this setting. For example, the review did not specifically examine second-generation anti-androgen agents or concomitant androgen blockade. The MARCAP consortium is planning to investigate how ADT use affects quality of life.
Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
Kishan AU, Sun Y, Hartman H, et al. Androgen deprivation therapy use and duration with definitive radiotherapy for localised prostate cancer: an individual patient data meta-analysis. Lancet Oncol. Published online January 17, 2022. doi:10.1016/S1470-2045(21)00705-1