Factors Associated With Risk Stratification and Overall Survival of Black South African Men With Non-Metastatic Prostate Cancer.

BACKGROUND

Emerging evidence indicates significantly poorer overall survival for men with metastatic prostate cancer in resource-limited settings than in high-income countries. However, there is less understanding of the overall survival of non-metastatic disease, which could inform early treatment strategies.

OBJECTIVE

To prospectively examine factors associated with the National Comprehensive Cancer Network (NCCN) risk stratification and overall survival in 741 Black South African men with non-metastatic prostate cancer, some of whom also had co-morbidities (≥ 2 other chronic conditions).

METHODS

Baseline data on social and health factors were collected. Follow-up of participants monitored overall survival over a median of 4.3 (3.5-5.0) years. We used multivariable proportional ordinal regression to examine factors associated with non-metastatic prostate cancer risk stratification. Kaplan-Meier, Cox proportional hazards regression, and Pohar-Perme methods were used to calculate overall survival and assess associations.

RESULTS

Our findings showed a generally favourable prognosis of non-metastatic prostate cancer with a 5-year overall survival of 79.0% (75.6-82.6) while the 5-year age-standardised net survival was 91.0% (95% CI 86.0-97.0). Overall survival differed significantly by the different NCCN risk groups, emerging early and widening over time, with the lowest survival in the high-risk groups. Only older age at diagnosis (Hazard Ratio per one-year increase:1.05 (95% CI: 1.02-1.08)), diabetes (HR: 1.70 (95% CI: 1.08-2.67)), and depression (HR: 1.67 (95% CI: 1.09-2.57)) at study recruitment were associated with poorer overall survival. Furthermore, only older age at diagnosis (HR: 1.04 (95% CI: 1.02-1.07)) was associated with higher non-metastatic prostate cancer risk.

CONCLUSIONS

These findings emphasise the need to address early diagnosis and comorbidities in non-metastatic prostate cancer, which could improve overall survival.