CT-guided transgluteal biopsy for systematic sampling of the prostate in patients without rectal access: a 13-year single-center experience

Objectives: The purpose of our study was to examine the safety and diagnostic utility of transgluteal CT-guided prostate biopsy for prostate sampling in patients without rectal access. Methods: Seventy-three biopsies were performed in 65 patients over a 13-year period (2002–2015). Mean prostate-specific antigen (PSA) at biopsy was 7.8 ng/mL (range 0.37–31.5). Electronic medical records were reviewed for procedural details and complications. Mean PSA and number of cores in malignant and benign cohorts were compared with Student’s t test. Results: Technical success rate was 97.3% (71/73; mean cores 8, range 3–28). Of these, 43.6% (31/71) yielded malignancy (mean Gleason score 7, range 6–10) and 56.3% (40/71) yielded benign tissue. The only complication was an asymptomatic periprostatic hematoma (1/73; 1.4%). In 14 patients who underwent surgery, Gleason scores were concordant in 71.4% (10/14) and discordant in 28.6% (4/14; Gleason 6 on biopsy but Gleason 7 on surgical specimen). Mean effective radiation dose was 18.5 mSv (median 15.0, range 4.4–86.2). There was no significant difference in either mean PSA (p = 0.06) or number of core specimens (p = 0.33) between malignant and benign cohorts. Conclusion: CT-guided transgluteal prostate biopsy is highly safe and reliable for the detection of prostate cancer in men without rectal access. Key Points: • Prostate cancer detection in men without rectal access is challenging. • CT-guided transgluteal prostate biopsy is safe and effective in these patients. • CT-guided biopsy may be particularly effective in diagnosing high-grade prostate cancer. • Unilateral CT-guided biopsy may be effective in patients with focal lesions. • The radiation exposure with this technique is acceptable.