Geographic and outcome variation among black men diagnosed with prostate cancer

Prostate cancer is the sixth leading cause of death from cancer among men worldwide. We have previously reported that prostate cancer survival rates for Caribbean-born males in the US was similar to survival rates of African-Americans and was higher than their counterparts diagnosed in the Caribbean. However, it is not clear whether differences in mortality could be attributed to differences in treatment. This current analysis seeks to further explore reasons for the geographic variation of prostate cancer survival for Caribbean-born men. This analysis included 2,554 Black newly diagnosed prostate cancer cases (960 cases diagnosed in the US and 1,594 cases diagnosed in the Caribbean). Clinical data were extracted from the cancer registry and clinical charts. There were noted differences in the pattern of treatment for each place of birth category when stratified according to disease stage at diagnosis. Among the patients diagnosed with early-intermediate disease (stage I-III) the majority of US-born Brooklyn men were treated with surgery only (31%) and a similar pattern was observed for Caribbean-born Brooklyn men (35%). In contrast, the majority of Caribbean-born Trinidad & Tobago men were treated with hormone therapy (31%). Caribbean-born men diagnosed in the Caribbean had a significantly higher risk of death from prostate cancer (Adjusted Hazard [AdjHR]: 3.7, 95% Confidence Interval [CI]: 2.8-5.0) when compared with the risk of death for Caribbean-born males diagnosed in the US. This observation was consistent for each treatment group with the exception of the cases treated with hormone therapy only. For these cases, there was no difference in the risk of death between Caribbean-born males diagnosed in the Caribbean (AdjHR: 1.4, 95% CI: 0.8-2.6) compared to Caribbean-born males diagnosed in the US. In addition to difference in access and utilization of screening, differences in treatment strategy may also be a strong predictor of outcome for Caribbean-born males diagnosed with prostate cancer. Further studies are needed to confirm these findings. In addition, other environmental factors related to survival that was not considered in this analysis also need to be investigated.