Multiparametric Magnetic Resonance Imaging of Penile Cancer: A Pictorial Review

The role of multiparametric magnetic resonance imaging (mpMRI) in assessing penile cancer is not well defined. However, this modality may be successfully applied for preoperative staging and patient selection; postoperative local and regional surveillance; and assessments of treatment response after oncological therapies. Previous studies have been mostly limited to a few small series evaluating the accuracy of MRI for the preoperative staging of penile cancer. This review discusses the principles of non-erectile mpMRI, including functional techniques and their applications in evaluating the male genital region, along with clinical protocols and technical considerations. The latest clinical classifications and guidelines are reviewed, focusing on imaging recommendations and discussing potential gaps and disadvantages. The development of functional MRI techniques and the extraction of quantitative parameters from these sequences enables the noninvasive assessment of phenotypic and genotypic tumor characteristics. The applications of advanced techniques in penile MRI are yet to be defined. There is a need for prospective trials and feasible multicenter trials due to the rarity of the disease, highlighting the importance of minimum technical requirements for MRI protocols, particularly image resolution, and finally determining the role of mpMRI in the assessment of penile cance

Multi-parametric MRI without artificial erection for preoperative assessment of primary penile carcinoma: A pilot study on the correlation between imaging and histopathological findings

Purpose: We aimed to evaluate the diagnostic potential of non-erectile multi-parametric magnetic resonance imaging (mpMRI) for preoperative assessment of primary penile squamous cell carcinoma (SCC). Method: Twenty-five patients who underwent surgery for penile SCC were included. Preoperative mpMRI without artificial erection was performed in all patients. The preoperative MRI protocol consisted of high-resolution morphological and functional sequences (diffusion-weighted imaging and dynamic contrast-enhanced MRI perfusion) covering the penis and lower pelvis. T and N staging, according to the 8th edition of the Union for International Cancer Control TNM classification, as well as the largest diameter and thickness/infiltration depth of the primary lesions were determined in all patients. Imaging data were retrospectively collected and compared with the final histopathology reports. Results: Very good agreement was observed between MRI and histopathology for the involvement of corpus spongiosum (p = 0.002) and good agreement was observed for the involvement of penile urethra and tunica albuginea/corpus cavernosum (p < 0.001 and p = 0.007, respectively). Good agreement was observed between MRI and histopathology for overall T staging and weaker, but still good agreement was observed for N staging (p < 0.001 and p = 0.002, respectively). A strong and significant correlation was observed between MRI and histopathology for the largest diameter and thickness/infiltration depth of the primary lesions (p < 0.001). Conclusions: Good concordance was observed between MRI and histopathological findings. Our initial findings indicate that non-erectile mpMRI is useful in preoperative assessment of primary penile SCC