Patient- and tumor-level risk factors for MRI-invisible prostate cancer.

BACKGROUND

Multiparametric MRI is highly sensitive for detection of clinically significant prostate cancer, but has a 10-20% false negative rate. It is unknown if there are clinical factors that predict MRI invisibility. We sought to identify predictors of MRI-invisible (MRI(-)) disease.

METHODS

Men undergoing MRI/US-fusion targeted + systematic biopsy by two surgeons at our institution from 2015 to 2018 were reviewed. Patient demographics, clinical data, MRI metrics, and biopsy pathology results were obtained by chart review. An MRI(-) tumor was defined as a positive systematic biopsy in a zone without an MRI lesion. Factors associated with presence of MRI(-) tumors were identified using stepwise multivariable logistic regression.

RESULTS

Of 194 men included in the analysis, 79 (41%) and 25 (13%) men had GG1+ and GG2+ MRI(-) tumors, respectively. On multivariable analysis, only Black race was associated with presence of GG1+ MRI(-) tumors (OR 2.2, 95% CI 1.02-4.96). Black race (OR 3.5, 95% CI 1.24-9.87) and higher PSA density (OR 2.0, 95% CI 1.34-3.20) were associated with presence of GG2+ MRI(-) tumors. In non-Black and Black men, detection of MRI(-) tumors on systematic biopsy upgraded patients from no disease to GG2+ disease 1% and 11% of the time, respectively, and from GG1 to GG2+ disease 42% and 60% of the time, respectively.

CONCLUSIONS

Black race and PSA density were associated with presence of MRI(-) prostate cancer. Further study on racial differences is warranted based on these results. Surgeons should consider pre-biopsy risk factors before deciding to omit systematic prostate biopsy regardless of mpMRI results.