Results of Finger-guided Transrectal Prostate Needle Biopsy Using an Iowa Trumpet

Abstract

Background and Objective: Currently, the gold standard diagnosis of prostate cancer is transrectal ultrasound
(TRUS)-guided prostate needle biopsy, obtaining 8 to 10 cores. Because Tak Hospital lacks a transrectal ultrasound,
finger-guided transrectal prostate biopsy using an Iowa trumpet was used. The aim of this study was to determine the
diagnostic values of this technique.
Methods: This retrospective study collected data from the hospital database from January 2006 to December
2015. Indications for biopsy included high prostate specific antigen (PSA) level (≥ 4 ng/mL) or abnormal findings
on digital rectal examination (DRE). Repeat biopsy was indicated in patients with rising PSA (> 0.85 ng/mL/year).
Patients with urinary tract infection and bleeding tendency were excluded. Pathological reports, PSA, and DRE
results were collected.
Results: Two hundred and fifty-two patients were included and 286 biopsies were performed. Cancer detection
rate at initial biopsy was 44%, and at the first repeat biopsy 17%. The sensitivity, specificity and positive predictive
value for PSA ≥ 4 ng/mL were 98.2%, 5.0% and 44.9%, respectively; for PSA level > 10 ng/mL these were 87.4%,
61.7% and 64.2%, respectively; for abnormal DRE, these were 90.1%, 87.9% and 85.5%, respectively; and for PSA
≥ 4ng/mL with abnormal DRE these were 88.3%, 92.9% and 90.7%, respectively. The major complications were seen
in 5% (most were infectious complication) and minor complications 9% (most were difficult urination, dysuria and
urinary retention) of patients.
Conclusion: Finger-guided transrectal prostate needle biopsy using an Iowa trumpet is equally as effective as
the standard TRUS-guided diagnosis of prostate cancer. Its complications are acceptable and comparable to the
standard TRUS-guided methods.