Multiparametric Sonography of Hematologic Malignancies of the Testis: Grayscale, Color Doppler, and Contrast-Enhanced Ultrasound and Strain Elastographic Appearances With Histologic Correlation

Multiparametric Ultrasound for Focal Testicular Pathology: A Ten-Year Retrospective Review

Conventional ultrasonography (US), including greyscale imaging and colour Doppler US (CDUS), is pivotal for diagnosing scrotal pathologies, but it has limited specificity. Historically, solid focal testicular abnormalities often led to radical orchidectomy. This retrospective study evaluated the utilisation of contrast-enhanced ultrasound (CEUS) and strain elastography (SE) in investigating intratesticular focal abnormalities. A total of 124 cases were analysed. This study underscored the superior diagnostic capabilities of CEUS in detecting vascular enhancement in all malignant cases, even those with undetectable vascularity by CDUS. It also highlighted the potential of CEUS in identifying distinctive vascular patterns in benign vascular tumours. Definitive confirmation of benignity could be obtained when the absence of enhancement was demonstrated on CEUS. While SE alone offered no distinctive advantage in differentiating between benign and malignant pathologies, we demonstrated that incorporating a combination of CEUS and SE into the evaluation of focal testicular abnormalities could improve diagnostic performance metrics over conventional CDUS. Our findings underscore the role of advanced ultrasound techniques in enhancing the evaluation of focal testicular abnormalities in clinical practice and could aid a shift towards testis-sparing management strategies.

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

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.

Primary Testicular Non-Hodgkin's Lymphoma With Bilateral Adrenal Metastasis: A Rare Presentation

Primary testicular lymphoma is the common testicular neoplasm in patients aged more than 65 years. It accounts for a small number of cases of adult testicular malignancies. Though the metastasis to bone marrow, liver, and central nervous system are well known, metastasis to adrenal glands is a very rare entity. It can be mistaken as a germ cell tumor or a dual malignancy. To rule out other causes, a multidisciplinary approach is required. Here, we present a rare case of primary testicular Non-Hodgkin's lymphoma with bilateral adrenal metastasis.

The clinical application of ultrasonography with superb microvascular imaging-a review

Superb microvascular imaging (SMI) is among the latest doppler ultrasound methods. It uses an advanced clutter filter to eliminate artifacts caused by breathing, movement and retains the low-speed blood signals in microvessels. The great advantage of SMI is that it can intuitively detect very slow blood signals in microvessels, providing clinicians with more significant information about flow distribution in the target area. Therefore, it is speculated that SMI has important application value. The purpose of this article is to outline the application of SMI in different parts of the body.

Ultrasonography findings for the diagnosis of renal oncocytoma

Renal oncocytomas are rare benign epithelial tumors of the kidney. However, they are easily misdiagnosed as renal cancers, resulting in unnecessary radical nephrectomy. This review summarizes the use of ultrasound for the diagnosis of renal oncocytomas. On two-dimensional grayscale ultrasound, renal oncocytomas appear as solid, well-defined, round or oval, and relatively isoechoic or slightly hyperechoic masses. On color Doppler flow imaging, the "spoke-wheel" sign is evident. On power Doppler flow imaging, renal oncocytomas show mixed penetrating and peripheral patterns. Renal oncocytomas usually appear as highly enhanced on contrast-enhanced ultrasound images, and irregular nonenhanced areas in larger tumors. This review will help sonographers recognize renal oncocytomas.

Contrast-enhanced and microvascular ultrasound imaging features of testicular lymphoma: report of five cases and review literature

Background

To retrospectively investigate the grey-scale, Doppler, contrast-enhanced and microvascular ultrasound of five patients with primary testicular lymphoma of our institute through review literature analysis.

Methods

From January to November 2020, five patients with primary testicular lymphoma confirmed by histology were preoperatively investigated with a standardized sonographic protocol including contrast-enhanced and microvascular ultrasound.

Results

Conventional ultrasound showed localized hypoechogenicity represented with solitary (2 of 5), multiple lesions (2 of 5), or entire testicular involvement (1 of 5). Increased blood flow appeared in color Doppler ultrasound with straight vascular sign (4 of 5). In contrast-enhanced ultrasound images confirmed this pattern (4 of 5) and presented hyper enhancement with enlarged range. On microvascular ultrasound imagings, all lesions were presented with straight and parallel course of intralesional vessels (5 of 5).

Conclusions

Here, we identified an increased vascularity with enlarged range on contrast-enhanced ultrasound along with a linear nonbranching pattern by vascular sign on microvascular ultrasonographic of testicular lymphoma.

Ultrasonography of the scrotum: Revisiting a classic technique

Conventional US is the primary imaging modality for the evaluation of the scrotum, due to its high resolution, availability, cost-effectiveness and absence of ionizing radiation. Grayscale and color Doppler US provide a comprehensive assessment of scrotal diseases. The technique represents the mainstay for imaging of acute scrotum. US is highly accurate in the detection, localization and characterization of scrotal masses. Multiparametric US, including conventional US, contrast-enhanced US and tissue elastography has improved the diagnostic performance of the technique in the assessment of testicular diseases. MRI represents a valuable supplemental imaging tool for the investigation of scrotal pathology, mainly recommended in cases of indeterminate US findings. Recommendations recently issued by the European Society of Urogenital Radiology Scrotal and Penile Imaging Working Group (ESUR-SPIWG) refer to the use of scrotal sonography for the evaluation of pathologic entities, including testicular microlithiasis, small, non-palpable incidentally detected testicular masses, varicocele and scrotal trauma. In this review, the technical specifications for scrotal US and the normal sonographic findings are presented. Grayscale and color Doppler US findings of common acute scrotal diseases and scrotal masses are discussed. The complimentary role of multiparametric US and scrotal MRI is addressed. ESUR-SPIWG's guidelines are also reviewed.

Incidental Findings and How to Manage Them: Testis- A WFUMB Position Paper

Testicular incidentalomas are non-palpable, asymptomatic lesions, most frequently detected on ultrasound examinations. Each incidentaloma should undergo a standardized diagnostic workup to exclude malignancy and recognize other potentially significant non-malignant conditions that may first present with an incidental finding on scrotal ultrasound. This position statement of the World Federation of Ultrasound in Medicine and Biology (WFUMB) summarizes the available evidence on management of testicular incidentalomas and describes efficient management strategies with particular reference to the role of ultrasound techniques.

Shear-wave elastography for the assessment of testicular involvement of hematologic malignancies in children and young adults: a feasibility study

Purpose

This study aimed to assess the feasibility of shear-wave elastography (SWE) for assessing the testicular involvement of hematologic malignancies in children and young adults.

Methods

Eight patients (mean age, 11.0 years; range, 0.8 to 20 years) with biopsy-confirmed testicular involvement of hematologic malignancy between January 2018 and December 2020 were retrospectively evaluated. Multiparametric ultrasound examinations, including grayscale, color Doppler ultrasonography (CDUS), and SWE, were performed. Stiffness was measured in the involved testicular area and contralateral normal parenchyma. If there was bilateral testicular involvement, the stiffness of the involved area and the adjacent normal echoic parenchyma was measured on one testis. The Mann-Whitney U test was used to compare stiffness values.

Results

On grayscale, the testicular lesions were noted as a solitary mass in one patient, multiple lesions in four patients, and diffuse involvement in three patients. On CDUS and SWE, all patients demonstrated increased vascularity, and the stiffness of the involved area was higher than the values of normal parenchyma (the involved area vs. normal parenchyma, 11.6 kPa [3.9-20.2 kPa] vs. 2.9 kPa [1.1-3.7 kPa], P=0.003). The ratio of stiffness between the involved area and normal parenchyma was 3.4, ranging from 1.9 to 5.1. One patient showed decreased stiffness on follow-up SWE after treatment (affected testis vs. normal testis: initial, 13.8 vs. 3.2 kPa; 1 year later, 2.2 vs. 2.4 kPa).

Conclusion

Increased testicular stiffness on SWE in children and young adults with hematologic malignancies suggests the possibility of testicular involvement.

Historical trends for the standards in scrotal ultrasonography: What was, what is and what will be normal

BACKGROUND

Ultrasonography is the gold standard imaging method for scrotal investigation. Colour Doppler ultrasonography, contrast-enhanced ultrasonography and sonoelastography allow sonographers to assess size, echotexture, vascular features and stiffness of the scrotal organs and abnormalities. Scrotal ultrasonography has been used to investigate male reproductive health, scrotal pain, masses and trauma. However, ultrasonography thresholds/classifications used to distinguish normal and pathologic features of the scrotal organs have changed over time, and have not yet been fully standardized.

OBJECTIVES

To evaluate historical trends for the standards in scrotal ultrasonography: what was, what is and what will be normal.

METHODS

An extensive Medline search was performed identifying the most relevant studies in the English language from inception to date.

RESULTS

We provide here (i) a brief overview of the history of ultrasonography, (ii) current indications for scrotal ultrasonography and (iii) previous and current normal values, cut-offs and classifications of the main colour-Doppler ultrasonography parameters/characteristics of the scrotal organs, as derived from recent guidelines and evidence-based studies. In addition, we report recommendations and the clinical utility of contrast-enhanced ultrasonography and sonoelastography. Finally, we discuss critical issues needing further evidence and future directions to fill in the current gaps.

DISCUSSION

Several studies on scrotal ultrasonography are available. However, guidelines/recommendations dealing with specific ultrasonography applications have been published only in recent years. More recently, the European Academy of Andrology published evidence-based scrotal colour-Doppler ultrasonography reference ranges/normative parameters derived from a cohort of healthy, fertile men. In addition, a standardization of the methodology to evaluate qualitative and quantitative colour-Doppler ultrasonography parameters was reported. Other international societies reported indications, methodological standards, clinical utility and limitations of contrast-enhanced ultrasonography and sonoelastography.

CONCLUSIONS

To date, colour-Doppler ultrasonography normative values for the scrotal organs are available. However, a wide international consensus on assessment and classification of several ultrasonography parameters is still lacking. An alignment of the world societies on these issues is advocated.

Paratesticular lesions: Aetiology and appearances on ultrasound

BACKGROUND

Ultrasound (US) is the primary modality for the investigation of scrotal pathology, including both intra- and paratesticular abnormalities.

OBJECTIVE

To describe the abnormalities of the paratesticular space.

MATERIALS/METHODS

The paratesticular space contains the epididymis, spermatic cord and the tunica vaginalis cavity and is affected by a variety of inflammatory or tumoral entities. Differential diagnosis based on US criteria is frequently problematic, as the findings are non-specific.

RESULTS

Some general rules apply: (i) unlike testicular lesions, extra-testicular entities are usually benign in the adult, (ii) the first steps to accurate diagnosis include careful localization of the lesion and assessment of its consistency (solid or cystic) and (iii) magnetic resonance imaging can be useful for further tissue characterization of lesions suspected to contain fat, but surgical biopsy will often provide the definite diagnosis. Contrast-enhanced ultrasound (CEUS) has been applied with limited experience indicating a narrow role, primarily for the differential diagnosis of echogenic cystic entities and the delineation of a necrotic abscess from a solid neoplasm.

DISCUSSION

The various abnormalities are discussed and illustrated.

CONCLUSION

This manuscript summarizes the literature on paratesticular lesions and the value of US in diagnosis.

Case Report: Testicular Sarcoidosis: The Diagnostic Role of Contrast-Enhanced Ultrasound and Review of the Literature

Sarcoidosis is a multisystemic disease histologically characterized by non-caseating epithelioid granulomas and multinucleated giant cells; the etiology is still uncertain, and likely related to a complex interplay between environmental and genetic factors. The genitourinary system is affected in fewer than 0.2% of all clinically diagnosed cases of sarcoidosis and in 5% of those identified in autopsy studies. In this report, we describe a case of a 42–year-old male with one hypoechoic lesion per testis on B-mode evaluation; contrast-enhanced ultrasound (CEUS) on both lesions was carried out. During the early phase, the masses showed a hypovascular appearance as compared to the surrounding testicular tissue, maintaining the hypo-enhancement in the late phase. Tissue biopsy for pathological evaluation confirmed testicular sarcoid involvement, showing non-caseating granulomas. Allowing visualization of testicular microvascularisation, CEUS may play an important role in excluding malignancy, avoiding unnecessary aggressive treatment for benign conditions, such as sarcoidosis. A review of the literature of reported cases since 2004 of sarcoidosis involving the testis is also included.

Vascularity of Intra-testicular Lesions: Inter-observer Variation in the Assessment of Non-neoplastic Versus Neoplastic Abnormalities After Vascular Enhancement With Contrast-Enhanced Ultrasound

The aim of this study is to assess the additional benefit of contrast-enhanced ultrasound (CEUS) over conventional ultrasonography (US) in identifying intra-testicular abnormalities among observers of different experiences. In this study, 91 focal testicular lesions (46 neoplastic, 45 non-neoplastic) imaged with gray-scale US/Doppler US and CEUS were classified using a 5-point scale. Three experienced and four inexperienced observers rated each lesion using gray-scale/color Doppler US alone and then with the addition of CEUS. Improved diagnostic specificity and accuracy with the addition of CEUS was observed for both experienced (specificity: 71.1% vs. 59.3%, p = 0.005; accuracy: 83.5% vs. 76.9%, p = 0.003) and inexperienced observers (specificity: 75.6% vs. 51.7%, p = 0.005; accuracy: 80.2% vs. 72.0%, p < 0.001). Significant inter-observer variability between the experienced and inexperienced observers when assessing conventional US alone was eliminated with the addition of CEUS. CEUS improves diagnostic accuracy of focal intra-testicular lesions for both experienced and inexperienced observers and reduces inter-observer variability in inexperienced operators.

Multiparametric ultrasonographic analysis of testicular tumors: a single-center experience in a collective of 49 patients

Purpose: The aim of the present retrospective single-center study is to evaluate the diagnostic performance of multiparametric ultrasonography for characterizing testicular tumors.Method: Forty-nine patients with testicular tumors, 36 of malignant vs 13 of benign entity, were included in this retrospective single-center study on whom multiparametric sonography, encompassing native B-mode, Color Doppler, contrast-enhanced ultrasound (CEUS) and elastography, was performed between 2011-2018. In 48 of 49 patients, findings from multiparametric analysis were correlated with histopathological results. The applied contrast agent for CEUS was a second-generation blood pool agent. Ultrasonography examinations were performed and interpreted by a single experienced radiologist with more than 15 years of experience (EFSUMB Level 3).Results: Multiparametric ultrasonography was successfully performed in all included patients without any adverse effects. Concomitant testicular microlithiasis, rapid arterial wash-in, elevated values for perfusion quantification - Peak Enhancement (PE), Wash-in Area Under the Curve (WiAUC) and Wash-in Perfusion Index (WiPI) - and higher shear wave velocities were significantly associated with malignancy.Conclusions: Multiparametric ultrasonography depicts a non-ionizing, directly accessible and cost-effective imaging modality that allows for the extensive characterization of testicular tumors, thereby helping to discriminate between malignant and benign entity of testicular tumors.

The role of tumor size, ultrasonographic findings, and serum tumor markers in predicting the likelihood of malignant testicular histology

The clinical predictive factors for malignant testicular histology remain unclear because of the low prevalence. Therefore, the aim of this study was to investigate predictors of malignant histology for testicular masses and decide more testis-sparing surgeries before surgery. This retrospective study enrolled 325 consecutive testicular mass patients who underwent radical orchiectomy (310/325) or testicular preserving surgery (15/325) from January 2001 to June 2016. The clinicopathological factors, including tumor diameter, cryptorchidism history, ultrasound findings, serum alpha-fetoprotein, and human chorionic gonadotropin (HCG) levels, were collected retrospectively for statistical analysis. A predictive nomogram was also generated to evaluate the quantitative probability. Among all patients, 247 (76.0%) were diagnosed with a malignant testicular tumor and 78 (24.0%) with benign histology. Larger tumor diameter (per cm increased, hazard ratio [HR] = 1.284, P = 0.036), lower ultrasound echo (HR = 3.191, P = 0.001), higher ultrasound blood flow (HR = 3.320, P < 0.001), and abnormal blood HCG (HR = 10.550, P < 0.001) were significant predictive factors for malignant disease in all testicular mass patients. The nomogram generated was well calibrated for all predictions of malignant probability, and the accuracy of the model nomogram measured by Harrell's C statistic (C-index) was 0.92. According to our data, the proportion of patients who underwent radical orchiectomy for benign tumors (24.0%) was much larger than generally believed (10.0%). Our results indicated that the diameter, ultrasonic echo, ultrasonic blood flow, and serum HCG levels could predict the malignancy in testicular mass patients.

Elastography of focal testicular lesions: current concepts and utility

As a relatively new sonographic technique, tissue elastography has emerged as a qualitative and potentially quantitative adjunctive tool to provide additional information on tissue stiffness, aiming to further improve diagnostic confidence in discriminating benign from malignant focal testicular lesions. The purpose of this review is to provide an overview of the elastography techniques used to assess focal testicular lesions and their typical appearance on tissue elastography.

Evaluation of Intratesticular Lesions With Strain Elastography Using Strain Ratio and Color Map Visual Grading: Differentiation of Neoplastic and Nonneoplastic Lesions

OBJECTIVE

To investigate the role of strain elastography using calculated strain ratio and visual elastography score in differentiating nonneoplastic, benign, and malignant neoplastic intratesticular lesions.

MATERIALS AND METHODS

The study was approved by the hospital review board as a retrospective review of 86 patients examined with gray scale, color Doppler ultrasonography and strain elastography (visual elastography score and strain ratio). Sensitivity, specificity, and positive and negative likelihood ratio of color Doppler and stain elastography were documented. Receiver operator characteristic curves assessed the diagnostic accuracy of strain elastography to discriminate nonneoplastic, benign, and malignant neoplasms. Histology or follow-up ultrasonography determined lesion character.

RESULTS

Thirty-one of 86 (36.0%) intratesticular malignant neoplasms, 17 of 86 (19.8%) benign neoplasms, and 38 of 86 (44.2%) nonneoplastic lesions were confirmed with histology (n = 52) or follow-up sonography (n = 34); 89.5% of intratesticular lesions were heterogeneous or hypoechoic on gray scale, with no difference between benign and malignant. Sensitivity, specificity, positive and negative likelihood ratio for nonneoplasm versus neoplasm were documented: color Doppler: 68.8%, 97.4%, 26.5, 0.32; visual elastography score: 81.3%, 57.9%, 1.93, 0.32; strain ratio: 68.8%, 81.6%, 3.73, 0.38. Neoplastic lesions showed a higher strain ratio than nonneoplastic lesions (P < .001), with strong correlation between median strain ratio and visual elastography score (Spearman's coefficient, 0.693; P < .001). Strain ratio is a significantly better assessment than visual elastography score for malignant lesions (P = .025). Logistic regression analysis revealed significant associations between size (P = .001), hypervascularity (P < .001), and malignancy.

CONCLUSION

Higher strain ratio and visual elastography score are associated with neoplastic lesions and offer an alternative to assess tissue characteristics but do not improve the diagnostic accuracy when compared with the color Doppler pattern.

Multiparametric US for scrotal diseases

Multiparametric US is increasingly recognized as a valuable problem-solving technique in scrotal pathologies. Compared to conventional Doppler modes, contrast-enhanced ultrasonography (CEUS) has higher sensitivity in assessing the presence or absence of flows, and to improve differentiation between poorly vascularized tumors and non-neoplastic, avascular lesions. Characterization of benign and malignant complex cysts is improved. In trauma patients, CEUS can help evaluating the viability of testicular parenchyma. In patients with severe epididymo-orchitis, it allows unequivocal assessment of post-inflammatory ischemic changes and abscess formation. CEUS does not add significantly to conventional Doppler modes in spermatic cord torsion. Attempt of differentiating benign and malignant tumors remains a research tool. In the clinical practice, elastography has a limited role for tumor characterization. The majority of malignant tumors are stiff at elastography, but they may display soft areas, or appear globally soft. A quantitative evaluation of testicular stiffness is feasible using shear-wave elastography. Potential clinical applications for elastographic modes could include work-up of infertile patients.