Multiparametric Ultrasound for Diagnosing Testicular Lesions: Everything You Need to Know in Daily Clinical Practice

Abstract

Background: Ultrasonography (US) represents the gold standard imaging method for the assessment of testicular lesions (TL). The gray-scale (GSUS) and color-Doppler (CDUS) ultrasound examination allow sonographers to investigate the size, margins, echotexture, and vascular features of TLs with the aim to differentiate benign from malignant lesions. Recently, the use of contrast-enhanced US (CEUS) and sonoelastography (SE) has led to further improvements in the differential diagnosis of TL. Although GSUS and CDUS are often sufficient to suggest the benign or malignant nature of the TL, CEUS can be decisive in the differential diagnosis of unclear findings, while SE can help to strengthen the diagnosis. The contemporary combination of GSUS, CDUS, CEUS, and SE has led to a new diagnostic paradigm named multiparametric US (mp-US), which is able to provide a more detailed characterization of TLs than single techniques alone. This narrative and pictorial review aimed to describe the mp-US appearance of several TLs.

Methods: An extensive Medline search was performed to identify studies in the English language focusing on the mp-US evaluation of TLs.

Results: A practical mp-US "identity card" and iconographic characterization of several benign and malignant TLs is provided herein.

Conclusions: The mp-US characterization of TL reported herein can be useful in daily clinical practice.

Keywords: color-Doppler ultrasound (CDUS); contrast-enhanced ultrasound (CEUS); differential diagnosis; gray-scale ultrasound (GSUS); multi-parametric ultrasound (mp-US); sonoelastography (SE); testicular lesions; testicular tumors; ultrasound (US).

Figure 1

Epidermoid cyst. GSUS demonstrates a well-circumscribed, solid, mixed-reflectivity lesion with high-reflectivity “onion-skin” peripheral rims (panel A), avascular in CDUS (panel B) in a 17-year-old male patient who was referred for testicular pain. SE shows a mixed elasticity lesion (panel C), demonstrated by a blue-green pattern, while contrast-enhanced US demonstrates a clear lack of enhancement within the lesion (panel D).

Figure 2

Embryonal carcinoma with internal necrosis (panel A) in a 30-year-old man referred for varicocele and atypical epidermoid cyst (panel B) in a 16-year-old boy referred for a lump in the testis: both demonstrate in CEUS a lack of vascularity.

Figure 3

Testicular adrenal rest tumor. GSUS (panel A) and CDUS (panel B) demonstrated bilateral hypoechoic lesions, highly vascularized, with irregular, lobulated margins in a 28-year-old man with congenital adrenal hyperplasia. In SE, they appeared as hard lesions (panel C). TARTs showed increased contrast-enhancement in CEUS (panel D).

Figure 4

Sarcoidosis. GSUS (panel A) and CDUS (panel B) demonstrated multiple small hypoechoic lesions with irregular margins and some internal vascular spots. In SE, sarcoidosis granulomas appeared as hard lesions (panel C). CEUS can confirm the presence of contrast-enhancement within the lesions (panel D).

Figure 5

Segmental testicular infarction. GSUS demonstrates hypoechoic lesions, mimicking a tumor (panel A) in a 28-year-old patient with a positive personal history of testicular cancer who was performing regular US follow-up. CDUS shows a lack of internal vascularization (panel B). CEUS confirmed the absence of vascularity within the lesion (panel C).

Figure 6

Abscess. GSUS demonstrated a focal, complex, heterogeneous low reflecting lesion with irregular margins (panel A). CDUS showed a hypervascular rim surrounding the lesion, with no internal vascular signal (panel B). In SE, testicular abscess showed a heterogeneous pattern of firmness (panel C). CEUS demonstrated the absence of internal contrast-enhancement with some peripheral enhancement (panel D).

Figure 7

Hematoma. GSUS demonstrated well-circumscribed anechoic lesions with septa and solid components (panel A) in a 38-year-old man referred after testicular trauma related to the ball of padel. CDUS showed a lack of internal vascularization (panel B). In SE, hematoma showed intermediate/high elastic strain (panel C), whereas CEUS confirmed the absence of vascularity within the lesion (panel D).

Figure 8

Idiopathic granulomatous orchitis. GSUS demonstrated multiple ill-defined, homogeneous, hypoechoic lesions (panel A) in a 24-year-old patient with a positive personal history of testicular cancer (seminoma) diagnosed 6-months earlier during his regular US follow-up. CDUS showed increased internal vascularization (panel B). In SE, the testis showed diffuse intermediate elastic strain (panel C), whereas CEUS confirmed the hyperenhancement within the lesions (panel D).

Figure 9

Tuberculous granulomatous orchitis. GSUS demonstrated focal hypoechoic lesions with blurred margins (panel A). CDUS showed only peripheric vascularization (panel B). In SE, tuberculous granuloma showed intermediate elastic strain (panel C). CEUS confirmed the hypoenhanced lesions with peripheral rim (panel D).

Figure 10

Seminoma. GSUS demonstrated a well-circumscribed homogeneously hypoechoic lesion in a 37-year-old man referred for infertility (panel A). CDUS showed increased internal vascularization (panel B). In SE, seminoma showed absent elastic strain (panel C), whereas CEUS confirmed the hyperenhancement within the lesion (panel D).

Figure 11

Embryonal carcinoma. GSUS demonstrated a markedly hypoechoic lesion (panel A) in a testis with starry sky appearance in a 29-year-old patient referred for testicular pain in the contralateral testis. CDUS showed peripheral and internal vascularization (panel B). In SE, the tumor showed absent elastic strain (panel C), whereas CEUS confirmed the hyperenhancement within the lesion (panel D).

Figure 12

Mixed germ cell tumor. GSUS demonstrated multiple markedly and mild hypoechoic lesions (panel A), occupying almost the entire testis of a 26-year-old patient referred for scrotal swelling. CDUS showed peripheral and markedly internal vascularization (panel B). In SE, the tumor showed intermediate/absent elastic strain (panel C). CEUS demonstrated hyperenhancement of the entire lesion (panel D).

Figure 13

Leydig cell tumor. GSUS demonstrated a well-defined hypoechoic lesion (panel A), with a hyperechoic halo in a 34-year-old man referred for primary infertility. CDUS showed peripheral and marked internal vascularization (panel B). In SE, the tumor showed an absent elastic strain (panel C). CEUS confirmed the hyperenhancement within the lesion (panel D).

Figure 14

Sertoli cell tumor. GSUS demonstrated a mild hypoechoic lesion (panel A) with irregular margins in a 46-year-old patient referred for hypogonadism. CDUS showed markedly internal vascularization (panel B). In SE, the tumor showed absent elastic strain (panel C). CEUS confirmed the enhancement within the lesion (panel D).

Figure 15

Lymphoma, nodular pattern. GSUS demonstrated a markedly hypoechoic lesion, with a multinodular aspect (panel A), with irregular margins, and interesting epididymis tail. CDUS showed markedly internal vascularization (panel B). In SE, the tumor showed an absent elastic strain (panel C). CEUS showed hyperenhancement of the lesions, with rapid wash-in and wash-out (panel D).

Figure 16

Leukemia. GSUS demonstrated a hypoechoic lesion (panel A) with regular margins. CDUS showed internal vascularization of the lesion (panel B). In SE, the lesion demonstrated an intermediate/soft elastic strain (panel C). In CEUS, the lesion appeared hyperenhanced due to its high vascularity (panel D).

Figure 17

Plasmacytoma. GSUS demonstrated multiple, both mild and markedly hypoechoic lesions (panel A) with smooth margins in a 72 year-old-man referred for scrotal swelling, with a positive personal history of plasmacytoma. CDUS showed internal vascularization of the lesions and hypervascularization of the entire testis (panel B). In SE, the lesions demonstrated intermediate elastic strain (panel C).