The Impact of Prostate Specific Antigen Testing on Incidence of Prostate Cancer cases in Zimbabwe

Prostate cancer is the leading cancer causing death in Zimbabwean men according to the Zimbabwe National Cancer Registry. By 2004 prostate cancer had become the most common cancer in Zimbabwean men. The incidence of prostate cancer shows strong age, race and geographical dependence. The prostate specific antigen (PSA) is a serine protease produced by cells of the prostate gland. The PSA blood test measures the level of PSA in man's blood and is used as a biomarker for prostate cancer (PCa). Unfortunately the PSA is prostate specific but not PCa specific. PSA testing started in Zimbabwe in 1995. The specific objectives of the study were: (i) to determine the age range most affected by PCa, (ii) to evaluate the impact of PSA testing on PCa cases in Zimbabwe. The study was a retrospective cross sectional study. Secondary data of all histology confirmed cases of PCa were obtained from the Zimbabwe National Cancer Registry (ZNCR) and analysed. Graph Pad Prism 7.03 was used to statistically analyse the data. The two-tailed T-test was employed to compare the number of pre-PSA cases against the number of post PSA era cases. 5277 PCa cases covering a thirty year period were retrieved. The first ten years (1986)(1987)(1988)(1989)(1990)(1991)(1992)(1993)(1994)(1995) were the pre PSA era period and the next twenty years (1996)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014)(2015) were the post PSA era. The median age was 71 (IQR 64-78) years. There was a significant difference between number of PCa cases of the pre-PSA era (1986)(1987)(1988)(1989)(1990)(1991)(1992)(1993)(1994)(1995) and the first post PSA era 1996 This showed the impact that PSA testing had on PCa in Zimbabwe (2006Zimbabwe ( -2015)). The study showed that the age group most affected by PCa was the 64-78 years. .