Needle size and transrectal prostate biopsy: A prospective comparative study of 16 gauge versus 18 gauge needles

Abstract

Background: The diagnosis of carcinoma of the prostate involves prostate biopsy and histopathological confirmation. While many urologists perform prostate biopsy using 18 gauge (18G) needles, larger 16 gauge (16G) needles have the potential of increasing the diagnostic yield from biopsy, which may in turn improve cancer detection rate. Objectives: The aim of this study was to evaluate the outcome of transrectal prostate biopsy with 16G tru-cut biopsy needle in comparison with 18G trucut biopsy needle. Methods: This was a randomized comparative study carried out at the University of Benin Teaching Hospital (UBTH), over a one-year period. Ninety patients who underwent biopsy were divided into two groups with 45 patients in each group. Group one had biopsy using size 16G needles, while group two had biopsy using 18G needles. Twelve cores were taken per patient. All patients were given antibiotics, beginning 24 hours before the procedure and continued for 5 days post biopsy. Results: Ninety patients underwent biopsy. Of the 45 patients who underwent biopsy using the 16G needles, 22 (52.4%) diagnosed with adenocarcinoma of the prostate. While in the 18G needle biopsy group, 20 (47.6%) were adenocarcinomas thereby showing an improvement in cancer detection of 4.4%, in favour of the 16G group. Patients that had biopsy using 16G needles reported slightly more pain during and after the procedure, than those in the 18G group. The commonest complication recorded was haematuria, seen in an equal number of patients in both groups. Conclusion: Transrectal prostate biopsy using 16G needle results in better quality of tissues, without increasing patient discomfort or other complications.