Clinical Characteristics and Survival of Patients With De Novo Metastatic Prostate Cancer Treated With Androgen Deprivation Therapy and Taxane-based Chemotherapy in Uganda: a Retrospective Cohort Study

Background: Prostate cancer is the second most common cancer among men worldwide. Mortality is highest among patients in resource-limited settings, in part due to late-stage disease. Among patients with metastatic prostate cancer (mPCa), studies have shown significant improvement in overall survival with the use of androgen deprivation therapy (ADT) and taxane-based chemotherapy. However, outcome data among patients treated with chemo-endocrine therapy are scarce in many resource-limited settings (RLSs). The aim of this study was to determine the clinical characteristics and 5-year overall survival (OS) of patients with de novo mPCa treated at the Uganda Cancer Institute (UCI). Methods: A retrospective cohort study was conducted between 2015 and 2019, and the data of patients with histologically confirmed prostate cancer and radiological evidence of metastasis were reviewed. Data on clinical and laboratory characteristics, overall survival, and predictors of survival were extracted. P<0.05 was considered to indicate statistical significance. Results: A total of 300 patients were enrolled over the 5-year study period. The median age was 68 (IQR 61.5-74) years. At presentation, lower urinary tract symptoms were reported in nearly all patients (96.7%, n=290), and 40% (n=120) of patients had grade 5 histological scores. In addition to receiving ADT, the majority of patients (70.3%, n=211) received at least 6 cycles of chemotherapy. Overall survival at one year was 92.4% (95% CI: 88.6%-94.9%), but it declined to 45.2% (95% CI: 36.8%-53.2%) at 5 years. A high Gleason score, the presence of visceral metastasis and receiving <6 cycles of chemotherapy were predictors of poor outcomes. Conclusion : Patients with de novo mPCa in Uganda present with high histologic grades and high baseline PSA levels but have improved 5-year overall survival with a combination of chemotherapy and ADT as a first-line treatment. We recommend interventions to reduce late presentation and prospective studies to evaluate treatment efficacy in this population.