The complementary role of digital rectal examination and prostate specific antigen for prostate cancer detection as seen Dar Es Salaam -Tanzania

Abstract

Background: Prostate cancer (PCA) is a significant public health problem. It is the most common malignancy and the second most common cause of cancer deaths among American men. In most of African countries its incidence is said to be unknown, probably because of poor quality of the medical care systems and registries which may have a substantial impact on the completeness and accuracy of the reported incidence rates. Digital rectal examination (DRE), PSA, Trans Rectal Ultrasound and needle biopsy remain standard tools for diagnosis of Prostate carcinoma worldwide. This study aimed to establish the diagnostic value of DRE and PSA among males suspected to have PCA at two Hospitals Dar es Salaam.

Methods: This was a cross sectional study which involved males suspected for PCA recruited by convenient sampling at Muhimbili national Hospital and Tumaini hospital. Data was collected by using structured questions. Each participating patient gave an informed consent. DRE findings and PSA values were sought from patient’s notes. Histopathology results were sought from Central Pathology Laboratory. Analysis was done with the aid of SPSS version 20 software.

Results: Three hundred and seventy-three patients were enrolled in the study with mean age 70.72 years and range from 45 to 102 years with a peak age of 61-70 years. The sensitivity, specificity and positive predictive value of DRE was 76.8%, 82.3% and 0.82 respectively; while for PSA respective values were 100%,29% and 0.47. Combination of DRE and PSA had a positive predictive value of 0.87making diagnosis accuracy of 87% when the two tests were combined.

Conclusion: Digital rectal examination and Prostate Specific Antigen provide good detection rate of prostate cancer when these two tests combined. In our study the diagnostic accuracy of DRE combined with PSA was 0.87. So as per WHO recommendations, these two tests should be used together since they complement each other if Trucut needle biopsy cannot be performed for any reason(s).

Keywords: Digital Rectal examination, prostate specific Antigen, prostate cancer