Education / Lap & Robotics / Surgical Innovations
Introduction & Objective :
The number of targeted magnetic resonance/ultrasound (MR/US) fusion prostate biopsies required to reach competency has not been evaluated. The primary aim of this study is to determine the minimum number of MR/US fusion biopsies that urologists need to perform to attain proficiency, as defined by a detection rate of clinically significant prostate cancer (CS-PCa) at or above the level of standard sextant biopsy in men with PIRADS 4 and 5 lesions on prostate MRI.
Methods : Three-hundred sixteen men underwent concurrent targeted and standard prostate biopsies from January 2016 to October 2017 at our institution. The detection rate of CS-PCa of targeted biopsy was compared to standard biopsy. CS-PCa is defined as intermediate risk group or higher based on NCCN guidelines, i.e. grade group 1 with PSA >10ng/mL or grade group 2 and above. Cumulative sum (CUSUM) analysis was used to produce a learning curve and determine the minimal number of targeted biopsies a urologist needs to perform to achieve a cancer detection rate at or above the rate of standard biopsy.
Four fellowship-trained urologists performed targeted biopsies at our institution with varying case volumes of 11, 39, 80, and 186 cases for surgeons 1 through 4, respectively. The overall CS-PCa detection rate was 32.9% (104 men) on combined targeted and standard biopsies. Targeted biopsy detected 75 cases (72.1%) whereas standard biopsy detected 76 cases (73.1%). CUSUM analysis of CS-PCa detection showed that two urologists (surgeons 3 and 4) achieved proficiency in targeted biopsy at 40 and 85 cases, respectively. After the first 40 targeted biopsies, surgeon 3's targeted biopsy rate improved from 36% to 52% while his standard biopsy rate remained at 44%, p<0.001. After the first 85 targeted biopsies, the CS-PCa detection rate on targeted biopsies by surgeon 4 improves by 7.9 fold (CI 1.15-41.3, p<0.02). Two urologists (surgeons 1 and 2) have not performed enough targeted biopsies to determine their proficiency.
Conclusions : The ACGME requires at least 25 TRUS biopsies for graduating urology residents. As MR/US targeted prostate biopsy becomes a routine diagnostic tool in the management of prostate cancer, it is important to define minimal number of targeted biopsies required to achieve proficiency with the new platform.