Calio BP, et al. - Researchers ascertained if ‘saturation’ of the index-lesion during MRI-TRUS fusion-guided (fusion) biopsy decreased the rate of pathological upgrade from biopsy to radical-prostatectomy (RP). A substantial decrease was brought to light in the risk of an upgrade on RP, by minimizing the impact of tumor heterogeneity, through the saturation of the index-lesion.

Methods

• The authors examined a prospectively maintained single institution database.
• The eligible candidates were patients who underwent both fusion and systematic biopsy followed by RP (2010-16).
• Index-lesion was defined as lesion with largest diameter on T2W-MRI.
• As a part of this trial, the patients with saturation of the index-lesion (SIL) had transrectal fusion biopsy targets obtained at 6mm intervals along the long axis of index-lesion; patients with nonsaturation of the index-lesion (NSIL) had only one target obtained from the lesion.
• Gleason 6, 7 and 8-10 were defined as low, intermediate and high risk category, respectively.

Results

• Researchers recruited 208 consecutive patients (86 with SIL and 122 with NSIL) with median (IQR) age and PSA of 62.0 (10.0)yrs and 7.1 (8.0)ng/ml, respectively.
• Median number of biopsy cores per index-lesion was higher in the SIL group (4 vs 2, p < 0.001).
• It was determined that the risk category upgrade rates from systematic only, fusion only and combined fusion/systematic biopsy results to prostatectomy were 40.9%, 23.6% and 13.8% respectively.
• Lower risk category upgrading from combined fusion/systematic biopsy results was obtained in SIL compared to NSIL group (7 vs 18%, p=0.021).
• No variation was found in the upgrade rates based on systematic biopsy between the two groups.
• Nonetheless, fusion biopsy results appeared to be substantially less upgraded in SIL group (Gleason upgrade: 20.9 vs 36.9%, p=0.014; risk category upgrade 14 vs 30.3%, p=0.006).