Conventional and diffusion-weighted magnetic resonance imaging findings of benign fibromatous paratesticular tumor: a case report

Abstract

Introduction: The vast majority of paratesticular masses are benign. Magnetic resonance imaging of the scrotum may provide valuable information in the pre-operative work-up of scrotal masses, by allowing the precise localization of the lesion and helping in characterizing its nature. Diffusion-weighted magnetic resonance imaging is an evolving technique that can be used to improve tissue characterization, when interpreted with the findings of conventional magnetic resonance sequences. We present the case of an adenomatoid tumor of the tunica albuginea, with abundant fibrosis evaluated by magnetic resonance imaging of the scrotum, including both conventional and diffusion-weighted sequences. To the best of our knowledge, there are very few reports in the English literature regarding the magnetic resonance imaging features of this rare benign paratesticular tumor and no report on the diffusion-weighted magnetic resonance findings. We discuss the value of magnetic resonance imaging in the pre-operative diagnosis of benign fibromatous paratesticular tumors and differential diagnosis.

Case presentation: A 45-year-old Caucasian man was referred to us with a palpable left scrotal mass. Magnetic resonance imaging of his scrotum revealed the presence of a multilobular left paratesticular mass, mainly detected with very low signal intensity on T2-weighted images and restricted diffusion on apparent diffusion coefficient maps. These findings were suggestive of a fibrous component, and were confirmed on histology following lesion excision.

Conclusion: Magnetic resonance imaging of the scrotum, by using both conventional and diffusion-weighted sequences, could have a potential role in the evaluation of scrotal masses.

Figure 1

Transverse T1-weighted image depicts a multilobular left scrotal mass (arrow), located in the paratesticular space. The lesion had similar signal intensity, when compared to the normal testicular parenchyma (asterisk). Left hydrocele (long arrow).

Figure 2

T2-weighted images (a) Transverse and (b) sagittal T2-weighted images show tumor heterogeneity. The mass (arrow) was mainly hypointense on T2-weighted images, a finding suggestive of the presence of fibrous tissue. Left hydrocele (long arrow). Normal left testis (asterisk).

Figure 3

(a) Transverse DW echo planar image (b = 900 mm²/s) and the (b) corresponding ADC map. The mass (arrow) appears mainly hypointense on DW images, due to the presence of abundant fibrous part. The ADC value of the fibrous component was 0.86 × 10^-3mm²/s. Left hydrocele (long arrow).