Can biopsies guided by multiple imaging techniques better detect disease progression?

This study examined the benefit of biopsies guided by multiple imaging techniques (scans that provide images of the interior of the body) in men managed with active surveillance. Researchers reported improved detection rates of disease progression when biopsies were guided by multiple imaging techniques.

Many men with low- to intermediate-risk prostate cancer may benefit from delaying treatment. Active surveillance (AS) refers to actively monitoring tumor growth without actually administering treatment.

The standard way to stage prostate cancer involves taking biopsies (tissue samples) from the prostate. Biopsies are typically done blindly, by systematically taking 10 to 12 separate tissue samples from different locations on the prostate gland. Biopsies guided by imaging techniques, such as magnetic resonance imaging (MRI), may better identify patients for AS. MRI plus ultrasound-guided biopsies have been commonly used for prostate cancer diagnosis. However, adding multiparametric MRI to MRI-ultrasound (fusion-guided biopsy) may provide a more effective alternative to standard biopsies. The ability of fusion-guided biopsies to detect progression in men already undergoing AS is less well understood.

The aim of this study was to evaluate the effectiveness of fusion-guided biopsies in monitoring men on AS.

The records of 166 men on AS were analyzed. 128 of these men had low-risk prostate cancer. 38 men had intermediate-risk prostate cancer. All men underwent a standard and a fusion-guided biopsy at the beginning of the study. Follow-up biopsies were carried out between 12 to 24 months on AS. Patients were followed for an average of 25.5 months.

35.1% of men with intermediate-risk prostate cancer showed disease progression. The average time until progression was 1.5 years. 29% of low-risk prostate cancer patients showed disease progression. The average time until progression was 2.1 years.

Standard biopsies detected 30.6% of men that showed disease progression. This was significantly lower compared to biopsies guided by MRI-ultrasound alone (44.9%). Fusion-guided biopsies detected the majority of progression in men with low-risk disease (67.6%) and intermediate-risk disease (75%).

At the follow-up, fusion-guided biopsy detected 26% more cases of progression compared to standard biopsy. Results from the first fusion-guided biopsy was a significant predictor of later disease progression. This analysis accounted for age and cancer extent.

Researchers concluded that fusion-guided biopsies increased the detection rate of disease progression in men undergoing AS.

This study only included patients on AS who had tumors visible during imaging. Results may differ for patients who have no visible tumors.