Improved Cancer Detection with Targeted Biopsies only: Results from a Multicenter Series Using KOELIS Fusion System

INTRODUCTION & OBJECTIVE:

We evaluated the accuracy of elastic fusion biopsy in different European Centers using a standardized approach with the Koelis system. Our aim was to assess the added value of systematic biopsies (SB) in addition to targeted biopsies (TB) with regard to cancer detection rate (CDR), according to PIRADS score.

METHODS:

We prospectively included 1.992 patients who underwent fusion biopsy with the Koelis system between 2011 and 2020 in 8 European institutions. Prostate biopsy was performed including TB (a median of 3 per target) plus SB (12 to 14 cores). CDR for all cancers and for clinically significant (cs) prostate cancer (PCa), defined as ISUP score ≥2, was evaluated. Predictors of PCa detection in TB only were assessed on uni- and multivariable analyses.

RESULTS:

The TB+SB CDR was 63% for all cancers and 39% for csPCa. SB in addition to TB improved the CDR by 4% for all cancers and 8% for csPCa. PCa was detected in 28%, 73% and 92% of PIRADS 3, 4 and 5 respectively . PIRADS 3 resulted in ISUP grade 1 in over 60% of cases, while the proportion of ISUP grade 4 and 5 markedly increased only in PIRADS 5. PSA-density (HR 45.3), elevated PIRADS score (HR 12.3) and digital rectal examination (HR 1.43) were predictors of CDR in TB on multivariate analyses.

CONCLUSION:

Koelis fusion biopsy achieves a high CDR. TB only can detect a wide majority of PCa, whilst SB contributes to a minority of diagnoses. High PSA density is a strong PCa predictor, whilst PIRADS 3 leads to PCa detection in <30% of cases, frequently clinically insignificant.