Ethnicity and its significance in the pathobiology of prostatic carcinoma in Southern Israel

Background: Several studies have noted ethnic differences in the natural history of prostatic carcinoma. Southern Israel has been regarded as a melting pot and, perhaps more than the rest of the country, has encouraged the ingathering of immigrants from several countries, as well as a large Bedouin community. Objectives: In an attempt to determine any differences that may exist in population groups in Israel, we have examined clinical and biologic markers in patients diagnosed with prostatic cancer in Southern Israel in 1996-2000. We wanted to demonstrate differences in the incidence and features of prostate carcinoma among the population groups in Southern Israel, and to evaluate their possible biologic significance. Methods: Clinical parameter features, including the ethnicity origin of patients with prostatic adenocarcinoma, were reviewed in a cohort of 189 patients seen between 1996 and 2000. Tissue sections from specimens in a subset of 40 of these patients who had undergone prostatectomy were studied by immunohistochemistry for TP53, Bcl-2, and chromogranin A using the ABC peroxidase method. These markers were chosen because of their suggested impact on the biology of this tumor. Clinical correlations were examined. Results: We confirm the presence of ethnic differences in the features of prostatic adenocarcinoma in our geographic area. Notably, patients of North African origin were treated surgically at a younger age than immigrants from East Europe. Higher total prostate-specific antigen levels and more robust tumor cell Bcl-2 expression were detected in the East European patients. The number of Bedouin subjects in our cohort of patients with prostatic cancer was much more limited than expected. No immigrants from Ethiopia were included in our study diagnosed with prostate carcinoma during this period. Conclusions: The proportion of patients of European, especially East European, origin was relatively high among the cohort of 189. Their older age and the lower proportion of subjects that underwent surgery, together with the tendency toward higher total prostate-specific antigen levels and higher Bcl-2 expression, suggest that this ethnic group may not differ significantly from the African-American group in the United States. The low representation of Bedouin and absence of Ethiopian immigrants among our patients with prostate cancer may point to a genuinely low incidence or it may be related to inadequate medical supervision in these population groups.