Colour Doppler and ultrasound characteristics of testicular Leydig cell tumours.

OBJECTIVE: To assess the colour Doppler and ultrasound features of testicular Leydig cell tumours (LCTs) in a population of 38 surgically proven lesions.

METHODS: From August 2008 to March 2015, we retrospectively included 38 surgically proven LCTs in 36 patients. Clinical data, scrotal colour Doppler, B-mode ultrasound and videos images were reviewed for each patient. The volume, echotexture of the testis, size, shape, echogenicity and the vascularization pattern of the lesion were evaluated. The tumour margins were categorized as either smooth or lobulated. The vascularization was classified as intense, moderate or without any hypervascularization. We defined the vascularization pattern groups as central, peripheral and mixed (the latter meaning both central and peripheral).

RESULTS: 26 patients were referred for infertility [5 patients were subsequently diagnosed with Klinefelter syndrome (KS) and 5 patients with cryptorchidism]. 28 patients underwent testis-sparing surgery, while 8 patients underwent a radical orchiectomy. The LCTs were mostly infracentimetric (68.4%), with a median size of 7.0 mm (ranging from 4.0 to 11 mm). 50% of the lesions had lobulated margins, and these were significantly larger than the smooth lesions (p < 0.05). The content of the lesions was markedly homogeneous and hypoechoic. All lesions had sharp demarcations from the adjacent pulp. 36/38 lesions exhibited moderate-to-intense hypervascularization, with a mixed intrinsic and peripheral rim pattern. Larger lesions were more hypervascularized (p < 0.05). LCTs in patients with KS had atypical features.

CONCLUSION: Typical sporadic LCTs appeared as isolated hypoechoic, infracentimetric masses, with a clear demarcation from the adjacent pulp. They presented intrinsic and peripheral rim hypervascularization.

ADVANCES IN KNOWLEDGE: By undertaking the largest imaging series of LCT to date (to our knowledge), we reassessed the typical sonographical aspects of LCTs, so as to provide guidance in regard to opting for testis-sparing surgery and for follow-up. LCTs present both intrinsic and rim vascularization detectable by colour Doppler ultrasound. Intrinsic vascularization and lobulated margins are common findings in testicular LCTs.