How to cite: Vargas A. “Why Are mpMRIs Negative in Men with Clinically Significant Prostate Cancer? Grand Rounds in Urology. October 23, 2025. Accessed Apr 2026. https://grandroundsinurology.com/why-are-mpmris-negative-in-men-with-clinically-significant-prostate-cancer/
Summary
Alberto Vargas, MD, Vice Chair of Oncology Imaging and Strategy, and Professor, Department of Radiology, New York University, New York, New York, explores why multiparametric prostate magnetic resonance imaging (MRI) can be negative in men who are later found to have clinically significant prostate cancer. Dr. Vargas frames the discussion around the idea that imaging findings should not be reduced to a simple dichotomy of positive or negative and emphasizes that tumor visibility is a spectrum.
Dr. Vargas explains how tumor visibility varies across imaging modalities, comparing ultrasound, computed tomography (CT), MRI, and positron emission tomography (PET). He notes that while there is some relationship between visibility across modalities, each provides different information. PET imaging is described as being more closely linked to tumor biology, while MRI and other modalities primarily reflect structural and morphological features.
He then discusses discordance between MRI and prostate-specific membrane antigen (PSMA) PET imaging, including differences in laterality and situations in which one modality is positive while another is negative. He emphasizes that the biological meaning of these discrepancies is not fully understood.
Dr. Vargas addresses the fact that some tumors are not visible on MRI, even when whole-mount prostatectomy specimens confirm their presence. Acknowledging that earlier studies often characterized these findings as false negatives, he explains what other pathological and genomic factors may influence visibility. He also discusses radiology workflow and technical factors that may limit tumor invisibility, such as image quality, resolution, noise, and artifacts.
Dr. Vargas emphasizes that an invisible tumor is not the same as a normal prostate MRI, and that all prostate MRIs show abnormalities. He discusses how reader perception, pre-test probability, prior biopsy results, and concern about missing cancer can influence how radiologists set thresholds for positive or negative findings.
Lastly, Dr. Vargas shares data suggesting that negative MRI findings can coexist with positive pathology, and that visibility or invisibility may have prognostic implications. He reasserts that tumor visibility should be considered in the clinical context, and that access to imaging, image quality, and reader expertise must be taken into account before drawing conclusions.
About the 28th Annual Southwest Prostate Cancer Symposium:
Presented by Program Chairs Nelson N. Stone, MD, Richard G. Stock, MD, and William K. Oh, MD, this conference educated attendees about advances in the management of localized and advanced prostate cancer, with a focus on imaging, technology, and training in the related devices. It included a scientific session, as well as live demonstrations of surgical techniques. You can learn more about the conference here.
ABOUT THE AUTHOR
Alberto Vargas, MD, is Vice Chair of Oncology Imaging and Strategy, and a Professor within the Department of Radiology at New York University in New York City. Dr. Vargas specializes in oncological and molecular imaging. His clinical and research interests focus on the use of advanced-imaging modalities, including diffusion-weighted and dynamic contrast-enhanced magnetic resonance imaging and novel positron emission tomography tracers for the non-invasive diagnosis, staging, treatment response assessment, and follow-up of patients with cancer. Dr. Vargas is especially interested in imaging patients with cancers involving the urinary system and the female reproductive organs.
