Intraprostatic locations of tumor foci of higher grade missed by diagnostic prostate biopsy among potential candidates for active surveillance

Abstract

To establish optimal biopsy scheme for selection of candidates for active surveillance (AS) among prostate cancer (PCa) patients, information on topographical distribution of tumor foci of higher grade missed by contemporary biopsy amongst potential candidates of AS would certainly be useful. Thus we analyzed topographic distribution of tumor foci by examining prostatectomy specimens in 444 patients who underwent radical prostatectomy for low risk PCa. Anterior and posterior prostate areas were demarcated by a horizontal line drawn at midpoint of prostatic urethra. Among 444 subjects, patients with upgrading showed relatively higher prevalence of index tumor foci in anterior prostate than those without upgrading, though not reaching statistical significance (p = 0.252). Meanwhile, among 135 (30.4%) patients with very low risk PCa, patients with upgrading showed significantly higher prevalence of index tumor foci in anterior prostate than those without upgrading (52.2% vs 33.8%; p = 0.031). In conclusions, tumor foci of higher grade missed by diagnostic biopsy were mostly located in anterior prostate among very low risk PCa patients. Such finding would be concrete evidence to support the notion that more efforts are needed to increase accuracy in detecting tumor foci in anterior prostate among potential candidates for AS.

Diagnostic performance of diffusion-weighted imaging for prostate cancer: Peripheral zone versus transition zone

“…From analyzing RP specimens, topographic analyses were performed on the intraprostatic location of tumor foci. Intraprostatic locations of tumor foci were assessed as previously reported [ 14 ]. The pathologic index tumor was defined as the tumor with the highest Gleason score (GS) and/or largest tumor when multiple foci had an identical GS.…”

“…As the patients with DWI grade ≤ II could not have index lesions, only patients with DWI grade ≥ III were evaluated in analyzing concordance between the pathologic and radiologic index lesions. When the location of pathologic index tumor assessed via previously-reported scheme was considered to correspond with the location of radiologic index tumor, the subjects were regarded to have the concordance of index lesions between preoperative MRI and surgical specimen [ 14 ]. High grade disease was defined as PCa having pathologic GS ≥ 4 + 3 from surgical specimens.…”

“…High grade disease was defined as PCa having pathologic GS ≥ 4 + 3 from surgical specimens. Tumor volume was calculated as previously described [ 14 – 15 ]. Following RP, patients were usually followed up as 3 to 6 month intervals during the initial 2 years and yearly thereafter.…”

Transition zone prostate cancer: Logistic regression and machine‐learning models of quantitative ADC, shape and texture features are highly accurate for diagnosis

“…clinically significant (Gleason score ≥ 7) PCa diagnosed after an initial negative template biopsy. 4,5 The use of multiparametric (mp) magnetic resonance imaging (MRI) (T 2 -weighted [T 2 W] MRI + diffusion-weighted imaging [DWI] + dynamic contrast-enhanced [DCE] MRI 6,7 ) for detection of TZ PCa (with eventual histological confirmation of PCa through image-guided targeted biopsy) has altered the clinical management of TZ tumors that were previously diagnosed by means of transperineal saturation biopsy. 8 While the use of mp-MRI and reporting by the Prostate Imaging and Data Reporting System (PI-RADS) version 2 (v2) guidelines have ameliorated the ability to diagnose TZ PCa in clinical practice, there remains room for improvement.…”

“…TRANSITION ZONE (TZ) prostate cancer (PCa) is a common clinical problem accounting for up to 20% of all PCa . TZ tumors are frequently undersampled or undetected at nontargeted transrectal ultrasound (TRUS)‐guided template biopsy and therefore represent a leading cause of treatment failure in men managed with active surveillance (AS) and for clinically significant (Gleason score ≥ 7) PCa diagnosed after an initial negative template biopsy . The use of multiparametric (mp) magnetic resonance imaging (MRI) (T 2 ‐weighted [T 2 W] MRI + diffusion‐weighted imaging [DWI] + dynamic contrast‐enhanced [DCE] MRI) for detection of TZ PCa (with eventual histological confirmation of PCa through image‐guided targeted biopsy) has altered the clinical management of TZ tumors that were previously diagnosed by means of transperineal saturation biopsy …”