How to cite: Vargas A. Clinical and Prognostic Implications of Cancer Visibility on Imaging: Radiology Perspective. Grand Rounds in Urology. September 15, 2025. Accessed Oct 2026. https://grandroundsinurology.com/clinical-and-prognostic-implications-of-cancer-visibility-on-imaging-radiology-perspective/
Summary
Alberto Vargas, MD, Professor and Vice Chair, Department of Radiology, New York University, New York, New York, examines the clinical and prognostic implications of prostate cancer visibility on imaging, with a focus on magnetic resonance imaging (MRI) from a radiological perspective.
Dr. Vargas explains that tumor visibility varies depending on the type of imaging modality used. Some tumors are detectable on ultrasound or computed tomography, but MRI remains the workhorse for staging, and prostate-specific membrane antigen positron emission tomography (PSMA PET) increasingly contributes to diagnosis and follow-up. He notes that up to 50 percent discordance exists between MRI and PSMA PET findings, underscoring the complexity of interpretation.
Dr. Vargas highlights that prostate tumors invisible on MRI have been recognized for more than 15 years. He outlines determinants of invisibility, including tumor size less than 0.5 mL, lower Gleason grade, histopathologic growth patterns, and genomic features. He emphasizes that technical factors such as image resolution and acquisition quality significantly affect visibility.
He stresses that “invisible” tumors are not equivalent to normal prostates. Rather, interpretation depends on the radiologist’s expertise and biases. Dr. Vargas argues that visibility and invisibility should be contextualized by the clinical setting, with implications differing between active surveillance and high-risk patients. In literature linking tumor visibility on MRI with prognosis, invisible tumors correlate with a very low probability of metastasis at 15 years, while visible tumors with extraprostatic extension carry a higher risk. Intermediate outcomes appear in discrepant cases where imaging and pathology findings do not align.
Dr. Vargas asserts that both imaging and non-imaging factors influence tumor visibility. He calls for careful consideration of access to MRI, image quality, and radiologist expertise in interpreting prostate MRI for prognostic and clinical decision-making.
The Global Summit on Precision Diagnosis and Treatment of Prostate Cancer is a unique multi-disciplinary forum organized to inform the key health care stakeholders about the emerging advances in clinical cases and research and create a consensus-based vision for the future of precision care and educational and research strategy for its realization. The mission of the Summit is to fill the currently existing gap between the key experts of in vivo imaging, the world authorities in the in vitro fluid- and tissue-based molecular diagnostics, including genomics, and thought leaders in the development of novel observation strategies (e.g., active surveillance, or AS) and therapeutic interventions.
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.
