Racial and ethnic variation of PSA in global population: Age specific reference intervals for serum prostate specific antigen in healthy South Indian males.

The serum PSA is universally accepted as the useful and clinically relevant tumor marker for monitoring therapy and identifying early recurrence in patients of carcinoma prostate throughout the world. However, application of serum PSA is limited to screening for early adenocarcinoma prostate among males above fifty years of age.Serum PSA concentration varies from one population to another in different parts of the world. Many groups of workers have selected 4 ng/ml of serum PSA as upper limit of normal range without giving due consideration for age specific increase in serum PSA. There is no single report available on normal decade wise age specific reference intervals for serum PSA in Indian males.The present study is undertaken to establish age specific reference intervals in healthy Indian males from 20-89 years belonging to subpopulation of Andhra Pradesh from South India. Our results revealed lowest concentration of 95 percentile serum PSA in Indian males compared to other populations globally. Contrary to this, healthy Afro Americans were found to have highest concentration of serum PSA compared to all other populations.