CASE 9988 Published on 21.03.2012

MR imaging in the characterisation of benign intratesticular mass lesion

Section

Uroradiology & genital male imaging

Case Type

Clinical Cases

Authors

Tsili AC¹, Argyropoulou MI¹, Ntoulia A¹, Tsampalas S², Silakos A², Gousia A³, Astrakas L⁴, Sofikitis N², Tsampoulas K¹

1 Department of Clinical Radiology
2 Department of Urology
3 Department of Pathology
4 Department of Physics
University Hospital of Ioannina, Greece.

Patient

45 years, male

Categories

Area of Interest Genital / Reproductive system male ; Imaging Technique Ultrasound, MR-Diffusion/Perfusion, PACS, MR

Procedure Comparative studies, Biopsy ; Special Focus Pathology ;

Show more Show less

Download as PDF Print Show related cases Notify admin

Clinical History

A 45-year old man was referred to the Urology department for vague scrotal pain. Sonographic examination revealed the presence of a hypoechoic right intratesticular mass lesion. Laboratory analysis was unremarkable. The patient had a history of surgery for undescended testis ispilaterally. MR imaging examination of the scrotum was followed.

Imaging Findings

Sonography of the scrotum revealed a heterogeneous solid intratesticular mass within a small-sized right testis (Figure 1). The lesion was well circumscribed and mainly hypoechoic, compared to testicular parenchyma. Color Doppler showed no lesion vascularity.
MR imaging examination confirmed the presence of an upper pole right intratesticular lesion (Figure 2). The mass had signal intensity slightly higher and extremely lower than that of normal testis on T1 and T2-weighted images, respectively. It was well demarcated, surrounded by a low signal intensity halo. No areas of restricted diffusion were noted within the lesion (Figure 3). Dynamic contrast-enhanced sequences revealed strong, peripheral lesion enhancement, with a ring-like pattern and gradual, progressive increase of enhancement on each successive contrast-enhanced image (Figure 4). MR imaging findings were suggestive for a benign diagnosis.
Right testicular biopsy was followed and histology reported testicular parenchyma with hemorrhagic necrosis and atrophic tubules (Figure 5).

Discussion

The majority of solid intratesticular masses are malignant and radical orchiectomy is the treatment of choice. However, it is extremely important to recognize various benign intratesticular mass lesions, including tubular ectasia of rete testis, epidermoid cyst, orchitis, fibrosis, infarction, testicular hemorrhagic necrosis, for which orchiectomy should be avoided. A possible diagnosis of benignity based on imaging findings may improve patient management and decrease the number of unnecessary radical surgical procedures. Alternative treatment planning, including follow-up, biopsy or partial orchiectomy may be justified in these patients [1-5].
Sonography represents the first line modality in the evaluation of scrotal diseases, allowing the characterization of many benign intratesticular mass lesions [6,7]. However, sonographic findings may be nondiagnostic or inconsistent with clinical examination, including incidentally found (subclinical) lesions. MRI examination of the scrotum has been reported as a valuable adjunct modality in the investigation of scrotal pathology, especially recommended in cases of inconclusive sonographic features, as in this patient. The advantages of the technique include a wide field of view and multiplanar capabilities, allowing simultaneous evaluation of both testicles, paratesticular spaces and inguinal regions, in addition to satisfactory anatomic information and superiority in tissue characterization [1-5]. MRI may provide satisfactory results in the preoperative characterization of the histologic nature of various intratesticular lesions, in terms of morphologic information and detection of the presence of fat, blood products, fibrosis, granulomatous and solid tissue within the masses [1-5,8-10]. However, Serra et al reported that MRI proved useful following a sonographic examination in approximately 5% of cases of scrotal mass lesions [5].
MRI of the scrotum, including a dynamic contrast-enhanced subtracted technique may provide valuable information about testicular blood flow [11-14]. The technique by providing both structural and functional information has been reported useful in the differentiation between extratesticular and intratesticular diseases and the characterization of intratesticular mass lesions [11, 14].
In this patient, MRI of the scrotum revealed the presence of hypointense intratesticular mass lesion on T2-weighted images, enhancing only peripherally after gadolinium administration, findings suggestive for a benign diagnosis. DCE subtracted MR sequences showed gradual and progressive increase of enhancement, followed by either a plateau or a slower increase until the end of the examination by both intratesticular lesion and normal contralateral testis, confirming the diagnosis of benignity. To further assess the clinical value of MRI, a comparison of the diagnostic performances of DCE MRI with sonography, including contrast-enhanced ultrasound is required.

Differential Diagnosis List

Testicular haemorrhagic necrosis and atrophy

Testicular haemorrhagic necrosis

Fibrosis

Testicular infarction

Final Diagnosis

Testicular haemorrhagic necrosis and atrophy

References

[1] Cassidy FH, Ishioka KM, McMahon CJ, Chu P, Sakamoto K, et al (2010) MR imaging of scrotal tumors and pseudotumors. Radiographics 30:665-683 (PMID: 20462987)

[2] Woodward PJ, Sohaey R, O\'Donoghue MJ, Green DE (2002) From the archives of the AFIP: tumors and tumorlike lesions of the testis: radiologic-pathologic correlation. Radiographics 22:189-216 (PMID: 11796908)

[3] Tsili AC, Argyropoulou MI, Giannakis D, Sofikitis N, Tsampoulas K (2010) Magnetic resonance imaging in the characterization and local staging of testicular neoplasms. AJR 194:682-689 (PMID: 20173145)

[4] Muglia V, Tucci S, Elias J, Trad CS, Bilbey J, et al (2002) Magnetic resonance imaging of scrotal diseases: when it makes the difference. Urology 59: 419-423 (PMID: 11880084)

[5] Serra AD, Hricak H, Coakley FV, Kim B, Dudley A, et al (1998) Inconclusive clinical and ultrasound evaluation of the scrotum: impact on magnetic resonance imaging on patient management and cost. Urology 51:1018-1021 (PMID: 9609643)

[6] Kim W, Rosen MA, Langer JE, Banner MP, Siegelman ES, Ramchandani P (2007) US MR imaging correlation in pathologic conditions of the scrotum. Radiographics 27:1239-53 (PMID: 17848688)

[7] Dogra VS, Gottlieb RH, Oka M, Rubens DJ (2003) Sonography of the scrotum. Radiology 227:18-36 (PMID: 12616012)

[8] Rouviere O, Bouvier R, Pangaud C, Jeune C, Dawahra M, Lyonnet D (1999) Tubular ectasia of the rete testis: a potential pitfall in scrotal imaging. Eur Radiol 9:1862-1868 (PMID: 10602964)

[9] Cittadini G, Gauglio C, Pretolesi F, Santacroce E, Derchi LE (2004) Bilateral epidermoid cysts of the testis: sonographic and MRI findings. J Clin Ultrasound 32:370-372 (PMID: 15293307)

[10] Fernandez-Perez GC, Tardaguila FM, Velasco M (2005) Radiologic findings of segmental testicular infarction. AJR 184:1587-1593 (PMID: 15855121)

[11] Watanabe Y, Dohke M, Ohkudo K, et al (2000) Scrotal disorders: evaluation of testicular enhancement patterns at dynamic contrast-enhanced subtraction MR imaging. Radiology 217:219-227 (PMID: 11012448)

[12] Choyke PL (2000) Dynamic contrast-enhanced MR imaging of the scrotum: reality check. Radiology 217:14-15 (PMID: 11012418)

[13] Watanabe Y, Nagayama M, Okumura A, et al (2007) MR imaging of testicular torsion: features of testicular hemorrhagic necrosis and clinical outcomes. J Magn Reson Imaging 26:100-108 (PMID: 17659558)

[14] Reinges MHT, Kaiser WA, Miersch WD, Vogel J, Reiser M (1995) Dynamic MRI of benign and malignant testicular lesions: preliminary observations. Eur Radiol 5:615-622

Case information

URL:	https://www.eurorad.org/case/9988
DOI:	10.1594/EURORAD/CASE.9988
ISSN:	1563-4086

Figure 1

Sonographic examination of the scrotum

Sagittal sonographic image of the right testis depicts an upper pole intratesticular mass (arrow). The lesion is sharply demarcated, inhomogeneous, mainly hypoechoic.

Transverse ultrasound image shows a small-sized right testis, with an intratesticular, hypoechoic mass lesion (cursors), measuring 13 x 9 mm.

Colour Doppler image reveals absence of lesion vascularity.

Figure 2

MR imaging examination of the scrotum, unenhanced images

Axial T1-weighted image shows right intratesticular lesion, slightly hyperintense, when compared to normal testicular parenchyma (not shown in this image).

Transverse T2-weighted image depicts right intratesticular mass (arrow), mainly homogeneous, with very low signal intensity, when compared to normal testis. A left hyperintense intratesticular lesion (arrowhead) is also detected, located in the mediastinum testis.

Coronal T2-weighted image shows right testicular mass (arrow), extremely hypointense, when compared to normal testicular parenchyma. The lesion is well delineated, surrounded by a hypointense halo.

Figure 3

DW MR images

Diffusion-weighted image (b=900 s/mm2) in transverse plane depicts lesion hypointensity (arrow).

Corresponding ADC map (Figure 4a). The ADC values of the lesion (arrow) were 1.22 s/mm2 (arrow), compared to those of the normal contralateral testis (1.11 s/mm2).

Figure 4

MR imaging examination, post-contrast images

Coronal dynamic contrast-enhanced subtracted image at delayed (180 sec) phase depicts peripheral lesion enhancement (arrow).

Time-signal intensity curve of right intratesticular mass, with the ROI placed in peripherally enhancing halo shows strong lesion enhancement, with gradual progressive increase of signal intensity.