Introduction

A multifaceted approach using commercially available prostate biomarkers to aid in the decision making for diagnosing and treating prostate cancer has taken place in recent years. We aim to determine if the 4K score and Michigan Prostate Score (MIPS) change cancer detection rates in PIRADS 3 or lower disease.

Methods

A retrospective review of 58 consecutive patients who underwent multi-parametric magnetic resonance imaging (mpMRI) of the prostate, 4k score and MIPS test between December 2015 and September 2016 was performed. Indications for mpMRI, 4k score and MIPS test included an abnormal digital rectal examination, elevated PSA, PSA velocity > 0.75 ng/ml/year, and patients on active surveillance. All 3 tests were ordered during the same clinic visit prior to knowing the results of the other test. We excluded patients with PIRADS score 4 or 5. Clinically significant cancer was defined as GS ? 7.

Results

A total of 17 patients (32 lesions) with PIRADS ? 3 and 4k score test underwent MRI/US guided fusion biopsy. Median PSA was 5.6 ng/ml (1st quartile: 4.49 ng/ml, 3rd quartile 10.14 ng/ml). Median age was 63.5 (1st quartile 57.5, 3rd quartile 67.25). Median 4k score was 21% (1st quartile 9%, 3rd quartile 62%). A total of 8 patients (47%) were diagnosed with prostate cancer. 7/8 patients (88%) had biopsies that were positive for clinically significant cancer (Grade group 2= 5) and 2/7 patients (29%) had high grade cancer GS?8 (Grade group 4= 1, Grade group 5= 1). 5 patients had 4k scores > 60% and all 5 patients were diagnosed with clinically significant prostate cancer on same session sextant biopsy. 2 of the 5 (40%) of patients had cancer diagnosed on both mpMRI/US guided fusion and random sextant biopsy. 3 of the 5 patients (60%) did not have clinically significant prostate cancer on mpMRI/US guided fusion biopsy but had CaP on same session sextant biopsy (Table 1), p < 0.001. There was no significant difference between the patients with high MIPS and MRI fusion biopsy cores or sextant biopsy cores, p = 0.61.

Conclusions

The 4K score may be a useful adjunct to mpMRI of the prostate in patients with PIRADS ? 3. In this series, patients with high 4k score were found to have high grade prostate cancer on same session random prostate biopsy that was missed on mpMRI guided fusion biopsy.

Funding

none