Metastatic brain tumors in two predominantly black hospitals: a statistical analysis.

A retrospective statistical analysis was done on metastatic brain tumors collected from two predominantly black hospitals in Washington, DC. A composite African series of metastatic brain tumors was also constructed for comparison. The results indicate that bronchogenic carcinoma is the predominant metastatic brain tumor (45.2 percent) among American blacks in Washington, DC, and chorioepithelioma, the most common (20.0 percent) among African blacks. In comparing these two series, much dissimilarity in the pattern of tumor distribution between these two genetically related ethnic groups suggests an important environmental role in the genesis of metastatic brain tumors.The present study also reveals a relatively high proportional frequency of prostatic carcinoma among metastatic brain tumors in blacks (3.8 percent in Washington, DC, and 2.1 percent in Africa).