Multimodality imaging of paratesticular neoplasms and their rare mimics

Extratesticular masses focusing on MRI findings

Scrotal masses, whether cystic or solid lesions, are routinely evaluated using ultrasonography. Magnetic resonance imaging (MRI) may be used for further investigation in cases with atypical findings, difficult diagnoses, large masses, and/or unclear relationships with the surrounding tissues. Scrotal solid masses are divided into intra- and extra-testicular masses. A staggering 90% of the intratesticular masses are malignant, whereas 75% of extratesticular masses are benign. Extratesticular masses are less common than intratesticular masses; however, some extratesticular masses present characteristic MRI findings. Familiarity with these specific MRI features of extratesticular masses is beneficial to radiologists, as appropriate diagnoses can help avoid unnecessary invasive treatments such as orchiectomy. In this review, we describe fibrous pseudotumors, polyorchidism, adenomatoid tumors, and scrotal leiomyoma as benign paratesticular masses, focusing on their characteristic imaging features on MRI. Although these tumors are extremely rare, their MRI findings are distinctive, and accurate diagnoses can prevent unnecessary orchiectomy. In addition, to demonstrate the pitfalls of diagnosing extratesticular masses, we present a case of seminoma misidentified as extratesticular masses due to large extensions outside the testis. Spermatic cord sarcoma, including rhabdomyosarcoma, leiomyosarcoma, and liposarcoma, and metastasis to the spermatic cord are described as malignant extratesticular masses. This review focused on extratesticular masses and elaborates the imaging findings that can aid in the accurate diagnosis using MRI.

Paratesticular metastasis from colorectal adenocarcinoma presenting as hydrocele: a rare case report and literature review

Colorectal cancer, with the liver being the most common site of distant metastasis, followed by the lungs and bones. Although reports of metastasis to the testis exist, paratesticular metastasis is extremely rare. A 37-year-old male presented with scrotal swelling. Ultrasound revealed hydrocele of the tunica vaginalis. The patient underwent routine surgical treatment, and postoperative pathology of the tunica vaginalis indicated adenocarcinoma of gastrointestinal origin. Colonoscopic biopsy confirmed adenocarcinoma of the sigmoid colon. After six months of systemic therapy, tumor reduction surgery was performed in conjunction with tunica vaginalis excision. Postoperative pathology suggested histological similarity in both sites, with immunohistochemistry results supporting the diagnosis of sigmoid colon adenocarcinoma metastasizing to the tunica vaginalis. We conducted a literature review, summarizing and discussing clinical presentations, metastatic pathways, and diagnostic approaches.

Soft-Tissue Sarcomas of the Genitourinary Tract with Radiologic-Pathologic Correlation

Genitourinary tract soft-tissue sarcomas are rare neoplasms with varied pathologic and clinical features. While some of these tumors may be aggressive high-grade malignancies, others are low grade with a relatively better prognosis. Given that the grade and extent of the disease are important prognostic factors in these tumors, timely diagnosis is crucial. Unfortunately, most imaging features of these malignancies are not pathognomonic, and various histologic subtypes do not manifest with typical classic imaging features. Therefore, reliable differentiation of the various histologic tumor types is not always possible based solely on the radiologic manifestations. Imaging findings need to be considered in the context of clinical history in corroboration with radiologic-pathologic correlation. The authors discuss the specific imaging and pathologic characteristics of various genitourinary tract soft-tissue sarcomas, emphasizing diagnostic difficulties and differential diagnoses. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

INternational Soft Tissue saRcoma ConsorTium (INSTRuCT) consensus statement: Imaging recommendations for the management of rhabdomyosarcoma

Rhabdomyosarcoma is the most common soft-tissue neoplasm in the pediatric population. The survival of children with rhabdomyosarcoma has only marginally improved over the past 25 years and remains poor for those with metastatic disease. A significant challenge to advances in treatment of rhabdomyosarcoma is the relative rarity of this disease, necessitating years to complete clinical trials. Progress can be accelerated by international cooperation and sharing national experiences. This necessitates agreement on a common language to describe patient cohorts and consensus standards to guide diagnosis, treatment, and response assessment. These goals formed the premise for creating the INternational Soft Tissue saRcoma ConsorTium (INSTRuCT) in 2017. Multidisciplinary members of this consortium have since developed international consensus statements on the diagnosis, treatment, and management of pediatric soft-tissue sarcomas. Herein, members of the INSTRuCT Diagnostic Imaging Working Group present international consensus recommendations for imaging of patients with rhabdomyosarcoma at diagnosis, at staging, and during and after completion of therapy. The intent is to promote a standardized imaging approach to pediatric patients with this malignancy to create more-reliable comparisons of results of clinical trials internationally, thereby accelerating progress in managing rhabdomyosarcoma and improving survival.

Paratesticular Ewing's sarcoma

This case report follows a 23-year-old man who presented with a painful right scrotal mass which was found to be a paratesticular vascular solid mass on ultrasound, and after uncomplicated orchiectomy, was revealed to be a high-grade extraskeletal Ewing's sarcoma. Diagnosis leading up to the orchiectomy was primarily clinical with only ultrasound used in identification and characterization of the paratesticular mass. Paratesticular masses are more commonly benign, and ultrasound is the first modality, with computed tomography and magnetic resonance imaging providing more definitive findings. We discuss imaging findings and histopathology of this rare tumor with an uncommon presentation.

Imaging Techniques to Differentiate Benign Testicular Masses from Germ Cell Tumors

PURPOSE OF REVIEW

To discuss role of different diagnostic imaging modalities in differentiation of benign testicular masses from seminomatous germ cell tumors (SGCTs) and non-seminomatous GCTs (NSGCTs).

RECENT FINDINGS

New modalities of ultrasonography, including contrast enhancement and shear wave elastography, may help differentiate between benign and malignant intratesticular lesions. Ultrasonography remains the recommended imaging modality for initial evaluation of testicular masses. However, MRI can be used to better define equivocal testicular lesions on US.

Multiparametric Ultrasound Diagnostic Approach to Malignancy-Mimicking Adenomatoid Tumors of the Scrotum: Is Strain Elastography Enough?

Background: Paratesticular tumors (PTs) are very uncommon, accounting for almost 5% of intrascrotal tumors. Of these, adenomatoid tumors (ATs) represent about 30% and most frequently arise in the tail of the epididymis. Ultrasound (US) examination is the first-choice imaging method employed for the evaluation of the scrotum. Unfortunately, there are no specific US-imaging features useful for distinguishing an AT from a malignant lesion. To increase diagnostic accuracy and confidence, new sonographic techniques have incorporated real-time tissue elastography (RTE) under the assumption that malignant lesions are "harder" than benign lesions. Case report: In our paper, we describe a very rare case of a 60-year-old patient with a giant paratesticular mass mimicking malignancy when examined using RTE, i.e., it was stiffer than the surrounding tissue (a hard pattern), which, upon histologic examination, was identified as an AT. Discussion: Our case underscores that there is also a significant overlap between different types of scrotal lesions when RTE is used for examination. Thus, if a PT is found, the imaging approach should always be supplemented with more definitive diagnostic methods, such as FNAC or FNAB, which are the only diagnostic methods capable of leading to a certain diagnosis. Conclusions: Alongside underlining the importance of pre-operative imaging for making correct diagnoses and selecting the correct therapy, we wish to draw our readers' attention to this report in order to demonstrate the clinical implications of a giant AT presenting as stiff lesions when examined using SE.

Para‑testicular arteriovenous malformation: A case report and mini‑review of the literature

Arteriovenous malformations from para-testicular structures are very rare, with only a limited number of cases reported in the literature. The present study reports a rare case of para-testicular arteriovenous malformation. A 6-year-old boy presented with painless swelling in the scrotum for 6 months. Upon examination, a non-tender and non-pulsatile cystic swelling was observed in the right hemi-scrotum below the testis. A scrotal ultrasound revealed a separate cystic lesion with a normal texture and the vascularity of both testes. Under general anesthesia, via a small scrotal incision, a cystic, blood-filled mass was excised. The results of a histopathological examination were suggestive of vascular malformation. The case described in the present study aims to shed light on vascular malformations. A number of vascular malformations are incorrectly referred to as hemangiomas, and numerous patients undergo inappropriate therapy due to this misclassification. Although para-testicular arteriovenous malformation is a very rare condition, it should be included in the differential diagnosis of para-testicular lesions.

Gamut of Extratesticular Scrotal Masses: Anatomic Approach to Sonographic Differential Diagnosis

The commonly taught tenet that intratesticular lesions are always malignant and extratesticular scrotal lesions are always benign is a simplistic statement that erroneously minimizes the significance of extratesticular scrotal masses and their diagnosis. Yet, disease in the extratesticular space is commonly encountered by clinicians and radiologists and is often a source of uncertainty in diagnosis and management. Given the embryologically rooted complex anatomy of this region, a wide range of pathologic conditions is possible. Radiologists may not be familiar with some of these conditions; further, many of these lesions can have a specific sonographic appearance, allowing accurate diagnosis that can minimize surgical intervention. Lastly, malignancies can occur in the extratesticular space-although this is less common than in the testicles-and proper recognition of findings that warrant additional imaging or surgery is critical in optimizing outcomes. The authors present a compartmental anatomic framework for differential diagnosis of extratesticular scrotal masses and provide a comprehensive illustrative display of many of the pathologic conditions that can be encountered to familiarize radiologists with the sonographic appearances of these lesions. They also review management of these lesions and scenarios where US may not be definitive in diagnosis and selective use of scrotal MRI can be helpful. ^© RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Adenomatoid Tumor of Epididymis Associated with Tubular Ectasia of Rete Testis: Sonographic Evaluation

Paratesticular tumors are a relatively rare group of mesenchymal tumors, accounting for 7%-10% of all intrascrotal tumors. Adenomatoid tumor of the epididymis is the most common epididymal tumor. It is difficult to distinguish intra- versus paratesticular tumors and to know the nature of the lesion (benign versus malignant) on clinical examination since they may have similar presentation; therefore, ultrasound examination of these lesions is required to demonstrate its extratesticular location and also to suggest its benign nature. Elastography can further help in characterizing the lesion by evaluating the stiffness of the tumor. Here, we present a case of adenomatoid tumor of the left epididymis with tubular ectasia of the rete testis.

Effects of radiotherapy on the survival of patients with malignant spermatic cord tumors: A retrospective cohort study

BACKGROUND

Malignant spermatic cord tumors (SCT) are rare and currently, there is no consensus regarding the role of radiotherapy in their treatment. This study evaluated the effect of radiotherapy on the overall survival (OS) of patients with malignant SCT based on the large-sample advantage of the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

Patients with malignant SCT recorded in the SEER database from 1975 to 2016 were included. All patients were divided into non-radiation and radiation groups, and propensity score matching (PSM) (1:1) was performed for baseline covariates between the two groups. The overall survival rate between the two groups of patients was analyzed using the Kaplan-Meier curve. The effects of radiotherapy on patient prognosis were analyzed using univariate and multivariate COX regression analyses.

RESULTS

In total, 389 patients with malignant SCT were included. There were 285 (73.26%) and 104 (26.74%) patients who either did or did not receive radiotherapy, respectively. Kaplan-Meier curves before and after PSM showed no significant differences in OS between the two groups. Similarly, multivariate COX regression models before and after PSM showed that radiotherapy was not an independent risk factor for OS in patients with malignant SCT.

CONCLUSIONS

Radiotherapy has no obvious advantage in improving the survival time of patients with malignant SCT.

Mesotheliomas and Benign Mesothelial Tumors: Update on Pathologic and Imaging Findings

A diverse spectrum of benign entities and malignant neoplasms originate from the monotonous mesothelium that lines the serosal membranes of the pleural, pericardial, and peritoneal cavities. The mesothelium of myriad sites shows a common origin from the lateral plate mesoderm; primary mesothelial tumors thus demonstrate similar pathogenesis, imaging findings, and treatment options. Significant changes have been made in the 2021 World Health Organization (WHO) classification schemata of the pleural and pericardial tumors on the basis of recent advances in pathology and genetics. While malignant mesotheliomas are biologically aggressive malignancies that occur primarily in patients exposed to asbestos with attendant poor survival rates, well-differentiated papillary mesothelial tumors and adenomatoid tumors charter a benign clinical course with an excellent prognosis. Mesothelioma in situ is a newly characterized entity represented by recurrent unexplained pleural effusions without any identifiable mass at imaging or thoracoscopy. Immunohistochemical markers based on BAP1, MTAP, CDKN2A, and TRAF7 gene mutations help differentiate diffuse mesotheliomas from benign mesothelial proliferations and localized mesotheliomas. Cross-sectional imaging modalities, including US, CT, MRI, and fluorine 18-fluorodeoxyglucose (FDG) PET/CT, permit diagnosis and play a major role in staging and assessing surgical resectability. Imaging studies are invaluable in providing noninvasive and quantitative assessment of tumor response in patients with unresectable disease. Owing to significant overlap in patient characteristics and pathomorphology, accurate diagnosis based on advanced histopathology techniques and genetic abnormalities is imperative for optimal management and prognostication. While patients with nonepithelioid pleural mesotheliomas benefit from immunotherapy, novel targeted therapies for CDKN2A-, NF2-, and BAP1-altered mesotheliomas are under consideration. ^© RSNA, 2023 Quiz questions for this article are available through the Online Learning Center.

Ultrasonographic manifestations and the effective diagnosis of epididymal leiomyosarcoma: Case report and systematic literature review

Background

Epididymal leiomyosarcoma is an extremely rare tumor. In this study, we describe the sonographic features of this uncommon tumor.

Methods

A case of epididymal leiomyosarcoma diagnosed at our institute was retrospectively analyzed. Ultrasonic images, noted clinical manifestations, treatment procedures, and pathology results were collected for this patient. The same information was collected from a systematic literature search on epididymal leiomyosarcoma, including the PUBMED, Web of Science and Google Scholar databases.

Results

The literature search resulted in 12 articles; we were able to extract data from 13 cases of epididymal leiomyosarcomatosis. The median patient age was 66 (35-78) years, and the average tumor diameter was 2-7 cm. All patients had unilateral epididymal involvement. The lesions were all solid, irregular-shaped in almost half of the cases, featured clear borders in six cases, and had unclear borders in four cases. The internal echogenicity was heterogeneous in the majority of lesions: six cases were hypoechoic (7/11) and three cases moderately echoic (3/10). Information on blood flow within the mass was provided in four cases, but all were noted with significant vascularity. Surrounding tissue invasion was discussed in 11 cases, with 4 featuring peripheral invasion or metastasis.

Conclusion

Epididymal Leiomyosarcoma demonstrates sonographic characteristics common to many malignant tumors, such as increased density, irregular shape, heterogeneous internal echogenicity, and hypervascular. Ultrasonography is helpful to differentiate benign epididymal lesions, and can provide some reference for clinical diagnosis and treatment. However, compared with other malignant tumors of the epididymis, it has no characteristic sonographic features,and pathological confirmation is required.

Ultrasonography of a giant adenomatoid tumor of the tunica vaginalis: A case report and review of the literature

Adenomatoid tumor is a kind of benign tumor, accounts for a low percentage of scrotal tumors. It usually locates in epididymis, less commonly, arises from the tunica albuginea, spermatic cord or tunica vaginalis of male's urogenital tract system. Here, we report a case of a 32-year-old male, which presented as a 6-month history of left scrotal swelling pain with a scrotal mass, and it had progressively enlarged over the last 1 month. The ultrasonography (US) described a giant well-defined hypoechoic mass in the left scrotum, a thick pedicle connected the mass and the left scrotal wall, and the pedicle had large blood vessels in it. Enhanced CT showed an irregular solid mass in the left scrotum, the left testicular artery was thickened to supply blood for the mass, and the radiologist mentioned it could not be excluded as a malignant lesion. The patient underwent left radical orchiectomy, the mass was diagnosed as an adenomatoid tumor of the tunica vaginalis by pathology. We review literature regarding adenomatoid tumors originating in the tunica vaginalis, summarize the ultrasonographic presentations, provide the idea of diagnosis and differential diagnosis to improve diagnostic accuracy and avoid unnecessary orchiectomy.

Paratesticular leiomyoma mimicking an inguinal hernia: A rare case report and literature review

Leiomyomas are considered as a rare, benign, slow-growing, and smooth muscle tumours which may present in all regions in the body. The presentation of leiomyoma in genitourinary tract specifically in paratesticular region is extremely rare. The patients may present with palpable, and painful mass in the inguinal region hence mimicking the nature of inguinal hernia. Herewith, we report our experience of 36-year-old male which had been referred for the suspicion of incarcerated inguinal hernia manifesting with painful mass in the right inguinal and testicular region. During testicular exploration surgery, a benign tumour was incidentally discovered. The lesions were then surgically removed by performing radical orchiectomy with the pathology result confirmed the presence of paratesticular leiomyoma. The post-operative course was uneventful and the patient was discharged on first post-operative day. The patient remained free from metastases or local recurrence after 12 months of regular follow up. This case report demonstrated a rare presentation of paratesticular leiomyoma with misleading manifestation of inguinal hernia. Careful and tailored investigation should be performed to avoid misled diagnosis of this case.

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Paratesticular leiomyoma is a rare benign tumour that may present similarly with ingunal hernia.

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Thorough clinical examination, imaging modalities, histopathology and immunohistochemistry may aid in the diagnosis.

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Surgical exploration is the mainstay treatment of paratesticular leiomyomas.

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Radical orchidectomy may be considered if malignancy is suspected.

Pathologic Conditions at Imaging of the Spermatic Cord

A wide range of benign and malignant processes can affect the spermatic cord (SC). Familiarity with and recognition of the characteristic imaging features of these entities are imperative for accurate diagnosis and optimal clinical care. While some SC diseases are self-limiting, others can result in infertility and potentially life-threatening infection or bleeding if they are left untreated. Therefore, correct diagnosis is important for life-saving treatment and preservation of fertility. Disorders including anomalies of the vas deferens and the processus vaginalis, arterial and venous diseases (torsion of the SC and varicoceles), infection, trauma, and neoplasms are the most pertinent entities with which radiologists should be familiar when assessing the SC. Knowing what to expect in a patient who has undergone SC interventions is imperative. US has a fundamental role in the initial examination of patients who present with symptoms that indicate abnormalities of the SC, such as suspected posttraumatic testicular retraction or SC torsion. Other imaging techniques including abdominal and pelvic MRI and CT have their own importance. For correct interpretation of the findings and to establish an accurate diagnosis, it is crucial to have a thorough knowledge of the anatomy, the utility and limitations of various imaging modalities, optimal imaging and scanning techniques, and the imaging features of various benign and malignant pathologic conditions that can involve the SC. Online supplemental material is available for this article. ^©RSNA, 2022.

The Dilemma in the Diagnosis of Paratesticular Lesions

Intra-scrotal swellings are commonly encountered all over the globe. Common causes include hydroceles, hernias, lipoma, cysts, etc. Rarely manifested as scrotal swelling is paratesticular swelling arising outside the testis. Clinically, they may mimic a tumour arising from testis either benign or malignant with grave consequences. Diagnosis hence is of paramount importance. It has to be ruled out as a diagnosis of exclusion. Knowledge of such swelling those other than the ones originating from the testis is thus crucial in order to have a better patient outcome in the absence of any mandated published guideline.

Pentaorchidism diagnosed on ultrasound examination: A case report and literature review

Polyorchidism is a congenital malformation of the urogenital system that is usually found incidentally in adolescent age groups. Ultrasound and MRI are effective non-invasive diagnostic modalities which can differentiate this condition from other intrascrotal pathologies. Ultrasonography is mostly used in initial steps of diagnostic approach; however, MRI is considered as a modality to confirm diagnosis and evaluate possible malignancy. We report an extremely rare case of pentaorchidism (five testicles), presented with a left hemiscrotum mass. Diagnosis was made based on physical examination, laboratory analysis (testicular germ cell tumour markers and semen analysis) and imaging. Finally, close surveillance with ultrasound and physical examination was recommended for follow-up of this uncomplicated patient.

Imaging in paratesticular lesions

A 23-year-old male presented with complaints of gradually increasing swelling of the left hemiscrotum. Preliminary ultrasound scan revealed a heterogeneous, predominantly solid lesion showing raised internal vascularity with few cystic areas in the paratesticular region, towards the midline with both testes seen separately from the lesion. To rule out presence of locoregional or distant metastases, a CT scan was done which revealed a well-defined, intrascotal, extratesticular, heterogeneous, moderately enhancing mass lesion with cystic areas in the scrotal sac with no significant lymphadenopathy or obvious distant metastasis. Subsequent MRI done for surgical planning revealed a heterogeneous signal intensity lesion with cystic areas and areas of haemorrhage with focal loss of fat planes with the left corpora cavernosa at the root of the penis. The patient underwent an inguinoscrotal exploration with excision of the left paratesticular mass. Final histopathology suggested an undifferentiated high grade pleomorphic sarcoma. Paratesticular tumours while rare are an important cause of scrotal swelling. Exact histological identification of tumour subtype is not possible based on imaging but preoperative multi-modality imaging has an important role in identifying tissue of origin, differentiating benign from malignant lesions, surgical planning and assessing the need for adjuvant CT/RT.

Scrotal Lipoblastoma with Radiological and Histological Correlation

Lipoblastomas are rare benign mesenchymal tumors comprised primarily mature adipocytes, which are most commonly found in infants and children younger than 3 years. They are usually found in the extremities, trunk, head, neck, and retroperitoneum, although cases occurring in the scrotum have been reported. Due to its rarity, there is a relative paucity of literature describing its imaging and management. We present a rare case of a scrotal lipoblastoma, and discuss the current imaging strategies to differentiate this adipocytic tumor from other more common paratesticular masses, including aggressive neoplasms such as rhabdomyosarcomas. Knowledge of the radiological appearance of lipoblastoma can provide the correct diagnosis and prevent unnecessary orchiectomy.

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.

The Rare, the Odd, and the Atypical: A Pictorial Essay of Testicular and Paratesticular Diseases

ABSTRACT

Understanding a variety of scrotal diseases is essential to developing an accurate differential diagnosis and is critical in providing optimal patient care. Ultrasound is the imaging modality of choice when evaluating for scrotal pathology, with the major purpose of locating such pathology to either the testis, or epididymis, or other intrascrotal structures, as well as characterizing lesions as solid or cystic. It is generally assumed that most solid intratesticular masses are more likely malignant, whereas most extratesticular ones are benign, although some exceptions to that rule exist. This pictorial essay will focus on rare and less commonly encountered benign and malignant testicular and paratesticular pathologies, which may pose a diagnostic dilemma for interpreting radiologists and treating physicians. Knowledge of their imaging characteristics will help narrow the differential diagnosis and assist in proper patient management and care.

Identifying the deceiver: the non-neoplastic mimickers of genital system neoplasms

Tumors of the genital system are common and imaging is of crucial importance for their detection and diagnosis. Several non-neoplastic diseases may mimic these tumors and differential diagnosis may be difficult in certain cases. Misdiagnosing non-neoplastic diseases as tumor may prompt unnecessary medical treatment or surgical interventions. In this article, we aimed to present the imaging characteristics of non-neoplastic diseases of the male and female genital systems that may mimic neoplastic processes. Increasing awareness of the imaging specialists to these entities may have a severe positive impact on the management of these patients.

When to ask for an MRI of the scrotum

Background

Multiparametric MRI (mpMRI) of the scrotum has been established as a useful second‐line diagnostic tool for the investigation of scrotal diseases. Recently, recommendations on clinical indications for scrotal MRI were issued by the Scrotal and Penile Imaging Working Group of the European Society of Urogenital Radiology.

Objective

To update current research on when to ask for an MRI of the scrotum.

Methods

PubMed database was searched for original articles and reviews published during 2010–2021.

Results

Eighty‐three articles fulfilled the search criteria. Scrotal MRI is mainly recommended after inconclusive US findings or inconsistent with the clinical examination and should be asked in the following cases: differentiation between intratesticular and paratesticular lesions (in rare cases of uncertain US findings), characterization of paratesticular and intratesticular lesions (when US findings are indeterminate), discrimination between germ cell and sex cord‐stromal testicular tumors, local staging of testicular malignancies (in patients planned for testis‐sparing surgery), differentiation between seminomas and non‐seminomatous tumors (when immediate chemotherapy is planned and orchiectomy is delayed), assessment of acute scrotum and scrotal trauma (rarely needed, in cases of non‐diagnostic US findings) and detection and localization of undescended testes (in cases of inconlusive US findings). Although preliminary data show promising results in the evaluation of male infertility, no established role for mpMRI still exists.

Conclusion

Multiparametric MRI of the scrotum, by assessing morphologic and functional data represents a valuable problem‐solving tool, helping to improve our understanding on the nature of scrotal pathology and the process of spermatogenesis. The technique may improve patient care and reduce the number of unnecessary surgical procedures.

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: Paratesticular Rhabdomyosarcoma

Paratesticular rhabdomyosarcoma (RMS) accounts for only 7% of all the RMS cases. Due to the limited available data, there is no consensus on the diagnosis and management of the paratesticular tumors. Here, we interrogated two paratesticular RMS cases in 25 and 27-year-old men presenting with painless and rapidly growing mass in the scrotum. Whereas the data showed no upregulation of tumor markers such as β-human chorionic gonadotropin (β-HCG), alpha-fetoprotein (AFP), and lactate dehydrogenase (LDH), scrotal ultrasonography and magnetic resonance imaging indicated the existence of paratesticular and inguinal lesions respectively. There was local recurrence in one patient who underwent radical orchiectomy for the sarcoma one year ago. In addition, the CT scans showed no occurrence of distant metastasis. The two patients underwent radical inguinal orchiectomy or resection of the recurrent tumors with nerve-sparing retroperitoneal lymph node dissection. Histologic examination revealed embryonal RMS (eRMS) without lymph node metastasis. We highlight the importance of multi-disciplinary participation for paratesticular RMS detection and preoperative ultrasound-guided needle biopsy (UNB) for rapid confirmatory diagnosis. Complete surgical resection coupled with chemotherapy and radiotherapy is the main treatment option for the paratesticular RMS. In addition, sperm cryopreservation treatment and endocrine follow-up could increase the overall survival and quality of life of the patients.

LIPOSARCOMA OF THE SPERMATIC CORD - DIAGNOSTIC AND THERAPEUTIC ISSUE

Liposarcoma of the spermatic cord is a malignant tumor so rare that there are less than 200 cases reported in the literature worldwide. Liposarcoma is a malignancy which originates from fat tissue. Although only 3%-7% of all paratesticular sarcomas primarily arise from structures of the spermatic cord, clinical significance of these tumors must not be neglected because they are often preoperatively misdiagnosed. A 66-year-old male presented with a painless swelling on the left side of the scrotum. Local examination revealed a solid, smooth, limited mass of approximately 4x3 cm in the left side of the scrotum. Tumor markers were within the reference range. Ultrasound examination showed a solid, clearly limited non-homogeneous mass of 40x20 mm localized in the left spermatic cord. Magnetic resonance imaging showed an expansive mass measuring 60x85x60 mm in the left inguinoscrotal region without propagation into the abdominal cavity. Both testicles and epididymides appeared normal on magnetic resonance examination and no locoregional enlarged lymph nodes were seen. The patient was treated operatively with radical inguinal orchiectomy. In conclusion, liposarcomas of the spermatic cord are extremely rare neoplasms that clinically present as slow-growing, painless, palpable inguinal or scrotal masses. Radical orchiectomy with high ligation of the spermatic cord and wide excision of the surrounding soft tissues within the inguinal canal remains the gold standard treatment option. Recurrence of the disease is frequent even several years after primary therapy, therefore long-term follow-up is mandatory.

A rare case of liposarcoma of the spermatic cord

We present a 42 year old man, who was admitted in the Urology Department with symptoms of unilateral, painless, hard and firm slow-growing mass of the left scrotum for 4 months. Pelvic computed tomography (CT) scan showed a 8 cm3 mass lesion in the left hemiscrotum. Left radical orchiectomy and wide excision were performed and a yellowish soft tissue mass measuring closely attached to the spermatic cord was resected during surgery. Histopathologic evaluation revealed a tumor mass composed of well-differentiated liposarcoma.

Rare benign and malignant testicular lesions: histopathology and management

PURPOSE OF REVIEW

The presence of vascular solid tumors within the testicle is considered to be malignant until proven otherwise. However, it is prudent for clinicians to be aware of rare benign and malignant intratesticular lesions as management can differ from the established treatment algorithms for germ-cell tumors.

RECENT FINDINGS

Utilizing certain histopathologic findings can assist with the diagnosis of rare testis tumors. Often times the tumor subtypes are an important consideration in the grading and classification of the disease, which drives management. The multidisciplinary management of rare malignant testis tumors at an experienced center seems to provide optimal patient outcomes. Regardless of the primary treatment, prolonged follow-up for sex cord stromal tumors and other rare testis malignancies is advocated due to the delayed metastatic potential.

SUMMARY

The clinical presentation of rare benign and malignant testis tumors is often similar to that of germ-cell tumors. Likewise, imaging characteristics are also often indistinguishable. However, the management of these rare tumors is often different from the well established treatment algorithms of germ-cell tumors. To that end, it is important for the practicing urologist to be familiar with the current principles of these tumor characteristics and the management.

Polyorchidism in ultrasound examination: A case report

Polyorchidism is usually diagnosed incidentally when the patient undergoes imaging or surgery for some other reason. Although we are facing lack of evidence in different steps of diagnostic and therapeutic workup of these patients, this disorder is usually considered benign, not requiring any intervention. We report the case of a man complaining of a palpable mass in his scrotum. We evaluated the patient using ultrasound, MRI and serum tumour marker level measurement. The patient was finally diagnosed with polyorchidism (three testes). For the management, we recommended annual physical examination, US examination and serum tumour marker level measurement.

Paratesticular rhabdomyosarcoma-Impact of locoregional approach on patient outcome: A report from the European paediatric Soft tissue sarcoma Study Group (EpSSG)

BACKGROUND

Paratesticular rhabdomyosarcoma (PT RMS) is rare compared to benign scrotal pathology. Inappropriate first surgery (InFS) required supplementary treatment to maintain excellent outcomes. Initial staging of regional lymph nodes is important. The aim of this study was to determine to what extent the quality of locoregional approach impacted on patient morbidity and survival.

DESIGN/METHODS

Analysis was performed on all nonmetastatic PT RMS patients enrolled in the European paediatric Soft tissue sarcoma Study Group (EpSSG) RMS 2005 protocol. Aspects assessed were adherence to surgical guidelines and impact of protocol violations, relapse analysis, and survival outcomes.

RESULTS

Analysis was performed on 237 patients, with median follow up of 67.1 months. Median age was 9.0 years. InFS occurred in 75 of 237 (32%) patients. InFS required intensified chemotherapy (10) and local therapy. After InFS, 61 required primary reexcision and five delayed surgery. Of 26 recurrences, the risk of relapse was higher in patients ≥10 years (21/26) and was mainly locoregional in 16 of 26 recurrences (± metastatic). Sixteen of 26 died with 14 of 16 patients ≥10 years. Nodal relapse neither occurred when N1 nodes were identified at diagnosis, nor after surgical staging. Five-year overall survival (OS) at age <10 years versus ≥10 years was 98.1 and 86.7%, respectively (P = .0013). Event-free survival (EFS) at age <10 years versus ≥10 years was 95.8 and 79.6%, respectively (P = .0004). OS and EFS did not highlight a significant difference in patients undergoing appropriate versus InFS (P = .8479, P = .2780, respectively).

CONCLUSIONS

InFS required intensified therapy to maintain excellent OS and EFS, so better anticipation of malignancy is required. Surgical staging of the retroperitoneal lymph nodes should be performed in patients ≥10 years old.

Radiologic Pathologic Correlation of Primary Paratesticular Rhabdomyosarcoma

Rhabdomyosarcoma is the most common soft tissue sarcoma in childhood and adolescence, arising from the mesenchymal tissue. It is an intrascrotal tumor localized in the paratesticular structures such as the epididymis or spermatic cord. The majority of this tumor occurs in the first two decades of life. Ultrasound is considered the imaging modality of choice for evaluating an intra-scrotal abnormality. We present a case of a 4-year-old boy with a 2-weeks history of rapidly increasing left scrotal swelling which was clinically diagnosed as hydrocoele. We present the ultrasound, elastography and MRI features of a case of paratesticular embryonal rhabdomyosarcoma with pathologic correlation and also emphasize need to consider sarcoma as a differential diagnosis for rapidly growing scrotal swelling.

Imaging of scrotal masses

Testicular cancer is responsible for approximately 0.1% of all cancer deaths in the USA, and seminoma is the most common type of testicular tumor. Ultrasonography is the primary imaging modality for accessing testicular and extratesticular lesions, while magnetic resonance imaging can be used for problem solving in lesion characterization in certain cases. CT imaging is usually performed for retroperitoneal staging of testicular cancer metastasis and follow-up after treatment. Extratesticular masses are common, yet rarely malignant. Imaging plays an important role in primary diagnosis of testicular cancer and differentiating it from common non-neoplastic findings. The purpose of this article is to review various imaging findings in testicular and extratesticular masses.

[Testicular tumors in prepubertal boys-organ preservation possible more often than expected]

In prepubertal boys, testicular tumors are rare with an incidence between 2 and 5/million. In contrast to testicular tumors in adolescents and adults, more than 2/3 of these tumors are benign. Unfortunately, in Germany in most cases, only malignant tumors (usually yolk sac tumors) are reported to the study center (MAKEI IV and now V). Therefore, the incidence in Germany is unknown. Since the introduction of polychemotherapy in the 1970s, the prognosis of malignant testicular tumors has improved enormously and has become a curable disease, even in the case of recurrence. Today the orchiectomy, which was usually carried out in the past, appears to be no longer justified in most prepubertal boys due to the high incidence of benign tumors. It has been shown in various studies that organ-sparing surgery in germ cell tumors (epidermoid cysts, teratoma); gonadal stoma tumors (Sertoli, Leydig and granulosa cell tumors) and cystic lesions (intratesticular cysts and tubular ectasia of the rete testis) is reliable and safe. In cases with preoperative significantly increased AFP (caution: norm values not valid in the first year of life) and a clear testicular tumor in the ultrasound (yolk sac tumor) or if no testicular parenchyma is sonographically detectable, orchiectomy can still be carried out. Today orchiectomies in prepubertal boys should be an exception and the reasons for an orchiectomy must be well documented.

Primary rhabdomyosarcoma of tunica vaginalis misdiagnosing as hydrocele: A case report and literature review

Primary rhabdomyosarcoma of tunica vaginalis is very rare. We report a case of a 15-year-old man presenting as hydrocele. Pre-operatively, no masses were detected by ultrasonography. Hydrocelectomy was performed. At surgery, a 0.8 cm polypoid nodule and diffusely thickened tunica were found. Pathologic examination finally revealed rhabdomyosarcoma. A PET-CT was then performed and indicated scrotal implantation metastasis. The patient underwent radical inguinal orchiectomy and was treated with chemotherapy and radiotherapy after surgery. At 12 months of follow-up, he remained disease-free.

Inflammatory myofibroblastic tumor of the spermatic cord: two cases and review of the literature

Inflammatory myofibroblastic tumor (IMT) is a neoplasm of intermediate biological potential. Few cases of spermatic cord IMT have been reported in the literature. Inflammatory myofibroblastic tumor is a consequence of the proliferation of fibroblasts and inflammatory cells. Despite its benign nature, the tumor often clinically mimics intrascrotal malignancy and usually remains undiagnosed preoperatively. The diagnosis of spermatic IMT is difficult preoperatively due to the non-specific findings. Therefore, if testicular tumors cannot be precisely excluded, radical orchiectomy should be performed for the diagnosis and treatment. However, it mainly occurs in children and young adults; spermatic IMT may also be seen among elderly men. Here, we report two cases of inflammatory myofibroblastic tumor involving the spermatic cord. SIMILAR CASES PUBLISHED: There are seven cases entitled "inflammatory myofibroblastic tumor of spermatic cord" in the literature. In our study we present two cases that had a spermatic cord IMT. Furthermore, one of these cases was 82 years of age and is the oldest patient presented in the literature.

A rare case of paratesticular leiomyoma in a child

Leiomyomas are benign, slow-growing, smooth muscle tumors, which can occur at many locations in the body. The male genitourinary tract is seldom affected and scrotal leiomyomas are extremely rare. Most of the scrotal leiomyomas are localized in the testis, epididymis, spermatic cord, subcutaneous tissue, tunica albuginea, and scrotal skin and only a few of them are reported in the origin of isolated tissue without paratesticular structures in the paratesticular region. We are presenting a case of solitary paratesticular leiomyoma in a child, which is very rare in terms of lesion location and patient age, and describing the imaging features of this lesion.

MR imaging of paratesticular bilateral leiomyoma: A case report

Paratesticular leiomyoma is a rare benign neoplasm that may arise from smooth muscle cells contained in either the epididymis, the spermatic cord, or the tunica albuginea. Usually patients present a palpable, asymptomatic mass, with a higher prevalence among the fourth and fifth decade of life. In this case report we describe a 57-year-old man with bilateral scrotal palpable masses evaluated with ultrasound and magnetic resonance imaging that were suggestive for leiomyoma. The lesions were surgically removed and pathology revealed no signs of malignancy confirming the diagnostic hypothesis of leiomyoma. Ultrasound is considered the imaging modality of choice for the initial evaluation of testicular masses since it allows an accurate localization (ie testicular vs paratesticular) and can identify signs of malignancy. Magnetic resonance imaging is less frequently performed but can considerably improve lesion characterization.

Scrotal Ultrasound

Ultrasound is the imaging modality of choice to evaluate the scrotum because of its high resolution, Doppler capabilities, availability, and lack of ionizing radiation. Acute urologic emergencies diagnosed with ultrasound include testicular torsion, testicular rupture, and Fournier gangrene. The radiologist's knowledge of sonographic features of vascular, infectious, traumatic, and benign and malignant processes that occur in the scrotum coupled with the patient's presenting symptoms, age, and physical examination allows for the correct diagnosis of a wide spectrum of scrotal pathology.

Paratesticular sarcomas: a case series and literature review

Paratesticular soft tissue tumours are remarkably rare entities, with malignant subtypes accounting for approximately 30%. Due to the paucity of cases, a consensus on the best treatment has not yet been reached, presenting a diagnostic and therapeutic challenge for clinicians. Although rare, three such cases presented to the care of our institution serving a population of approximately 400,000 in the space of 13 months. These were three gentlemen, aged 54, 82 and 86 years old, presenting with left sided testicular swellings. Ultrasound in each case confirmed an extratesticular mass. Only the second gentleman complained of associated pain, however he had experienced scrotal trauma in the preceding weeks. Only one patient had suspicions of metastatic disease, with a 9 mm pulmonary nodule on computed tomography. All patients underwent a radical inguinal orchidectomy with high ligation of the spermatic cord, in keeping with best accepted guidelines. Histology confirmed a well-differentiated liposarcoma, a dedifferentiated liposarcoma and a leiomyosarcoma respectively, all high grade. One gentleman returned to theatre for re-excision of margins. Our case series emphasises the need for full multidisciplinary team specialist sarcoma input, as well as radical resection with judicious margins in order to reduce the risk of local recurrence, in the treatment of these rare tumours.

Sonographically indeterminate scrotal masses: how MRI helps in characterization

Magnetic resonance imaging (MRI) of the scrotum represents a useful supplemental imaging technique in the characterization of scrotal masses, particularly recommended in cases of nondiagnostic ultrasonographic findings. An accurate characterization of the benign nature of scrotal masses, including both intratesticular and paratesticular ones may improve patient management and decrease the number of unnecessary radical surgical procedures. Alternative treatment strategies, including follow-up, lesion biopsy, tumor enucleation, or organ sparing surgery may be recommended. The aim of this pictorial review is to present how MRI helps in the characterization of sonographically indeterminate scrotal masses and to emphasize the key MRI features of benign scrotal masses.

MR Imaging of the Testicular and Extratesticular Tumors: When Do We Need?

Testicular ultrasound is typically the first-line imaging examination in evaluating scrotal pathology. However, MR imaging can often provide valuable additional information, especially when ultrasound and/or clinical examinations are inconclusive. This is particularly evident when encountering testicular or paratesticular lesions, where accurate localization and characterization are paramount for management and prognosis. After reviewing normal scrotal anatomy as seen on MR imaging and offering a sample imaging protocol, the article describes specific indications for scrotal MR imaging and highlights imaging findings unique to various benign and malignant causes.