Primary androgen deprivation therapy as monotherapy in unfavourable intermediate- and high-risk localised prostate cancer: a Singaporean single-centre perspective

Primary ADT (pADT) monotherapy is used significantly for patients with clinically localised disease in Asia and is acceptable even by guidelines, especially in intermediate- and high-risk disease. This occurs despite controversy in the West and data suggesting association with adverse effects, notably cardiovascular events. We therefore sought to assess the impact of pADT on all-cause mortality and prostate cancer-specific mortality (PCSM) in Asian men with high-risk and unfavourable intermediate-risk PCa.

With cancer registry data, men from a single centre in Singapore with clinically localised high-risk/unfavourable intermediate-risk PCa diagnosed between 2004 and 2014 and either treated conservatively with no therapy or started on pADT within 1 year of diagnosis were followed up through January 2017. Patients with non-localised PCa (clinical stage T4, regional/distant lymph node involvement, metastases), or receipt of local therapy (radical prostatectomy/radiotherapy) were excluded. The primary outcomes of all-cause mortality and PCSM were analysed with Cox proportional hazards regression models.

Three hundred and forty Asian men were analysed, and 177 (52.1%) were started on pADT, with mean age of 77 (49-98) years. There were 119 deaths in the cohort, and 68 (38.4%) occurred in patients treated with pADT (median follow-up, 4.4 years). After adjusting for comorbidities and clinical characteristics, pADT did not provide benefit to all-cause mortality, PCSM or cardiovascular mortality.

For clinically localised unfavourable intermediate-risk and high-risk PCa, starting pADT within 12 months of diagnosis is not associated with improved 5-year all-cause mortality or PCSM compared to patients treated conservatively with no therapy and should be discouraged due to lack of mortality benefit.

International urology and nephrology. 2018 Feb 28 [Epub ahead of print]

Han Jie Lee, Alvin Lee, Hong Hong Huang, Weber Kam On Lau

Department of Urology, Singapore General Hospital, 20 College Road, Academia, Singapore, 169856, Singapore. ., Department of Urology, Singapore General Hospital, 20 College Road, Academia, Singapore, 169856, Singapore.