Mesenchymal Extratesticular Tumors and Tumorlike Conditions: From the Radiologic Pathology Archives

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.

The Clinical Management of Intrascrotal Extratesticular Masses With Evaluation of Histopathologic Findings

OBJECTIVE

To contribute to the literature by sharing the clinical presentation, surgical approach, postoperative complications management, and follow-up protocols of the patients we operated on due to intrascrotal extratesticular mass.

METHODS

Thirty-two patients admitted due to intrascrotal extratesticular mass were included in the study. Demographic and clinical characteristics of the patients such as age, initial clinical presentation, physical examination, radiological imaging findings, such as scrotal Doppler ultrasonography and magnetic resonance imaging, mass size, and characteristics, surgical treatment procedures, operation notes, and patient follow-up visits were retrospectively examined and evaluated from the patient files.

RESULTS

The median age of the 32 individuals included in the study was 52 (interquartile range: [45.0-60.5]) years. The primary reason for initial presentation was a palpable mass in 25 (78.1%) patients, pain in 13 (40.6%) patients, and scrotal swelling in 8 (25%) patients. The median mass diameter was 4.4 (interquartile range: [3.1-5.7]) cm. Surgical treatment involved inguinal excision in 29 cases (90.6%) and inguinoscrotal excision in 3 cases (9.4%). All patients were treated with testicle-sparing surgery. The most common tumor location, observed in 27 cases (84.3%), was the epididymis. The most frequent histopathological diagnosis was epididymal cyst, identified in 13 patients (40.6%). Pathology results showed that the mass was removed with negative margins in all patients.

CONCLUSION

Testicular-sparing surgery through the inguinal approach is one of the surgical methods that can be preferred for intrascrotal extratesticular masses. This approach can both preserve the testicle and achieve successful surgical results. Studies with larger samples are needed on this subject.

TRIAL REGISTRATION

This study was approved by the Erzurum Medicine Faculty University Local Ethics Committee (approval number: BAEK 2023/08-105).

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.

Benign Paratesticular Fibrous Pseudotumor in a Young Male: A Case Report

Paratesticular fibrous pseudotumor (PFPs) is an uncommon intra-scrotal mass that originated from tunica vaginalis and resulted in a reactive fibrous proliferation after a history of inflammation, infection, trauma, or hydrocele. We report here on a case of a 17-year-old man with a mass in the hemiscrotum that was found to be PFP in the orchidectomy specimen pathologic examination. The diagnosis of PFPs, before and during the operation, can be complicated despite it being a benign tumor. Radical orchidectomy is usually performed for these types of lesions. A frozen section intraoperatively is essential to avoid unnecessary radical orchidectomy and preserve testicle.

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.

Scrotal leiomyoma: An uncommon cause of chronic scrotal swelling

Leiomyoma is a benign tumor that arises from smooth muscle. It may be encountered at any part of the body especially the uterus. However, scrotal localization is very uncommon, hence it often requires radiologic and pathology correlation to establish an accurate diagnosis and make optimal decisions for subsequent treatment. We present a case of an 82-years-old male, presenting with a left scrotal mass. Ultrasound and MRI demonstrated a left paratesticular mass. Surgery was then indicated and pathology results were consistent with a scrotal leiomyoma.

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.

Giant bilateral primary scrotal lipoma along with lipomas in multiple sites of the body: a case report and literature review

Mesenchymal neoplasms of the scrotum are extremely rare in the clinical practices, in which lipoma is the most common benign neoplasm of them. Primary scrotal lipoma refers to the lipoma originated from scrotal wall. We reported a rare case of a 47-year-old man who suffered from bilateral giant primary scrotal lipoma along with lipomas in multiple sites of the body. Scrotal ultrasound indicated that huge hypoechogenic masses were observed in the bilateral scrotums. Contrast-enhanced computed tomography (CT) indicated increased fat density in the scrotal areas. Surgical resection was performed on both scrotal neoplasms. Diagnosis of lipoma was confirmed by the pathological examination through the morphological observation as well as the absence of murine double minute2 (MDM2) gene amplification in the fluorescence in situ hybridization (FISH) test. After five months of follow-up, the wound of the patient recovered well and no sign of local recurrence was observed. Based on the literature review, very few cases of primary scrotal lipoma were reported in the scientific literature up to date, and this is the first report of bilateral primary scrotal lipoma along with multiple lipomas of the body. We presented this case as a rare phenomenon. Although primary scrotal lipoma is rare, clinicians should take it into account when encountering similar scrotal lesions and know the methods for diagnosis and how to make differential diagnosis with other diseases, which is associated with the patient's treatment strategy and prognosis.

Giant Primary Scrotal Lipoma: A Rare Entity with Diagnostic Pitfalls

Primary scrotal lipomas are rare. We describe the case of a 47-year-old male with a giant scrotal lipoma who underwent a surgical excision. We report the clinical and radiological approach as well as the treatment of this atypical benign tumor.

Imaging of Scrotal Tumors

음낭 종양은 고환, 부고환, 정삭, 고환막 등에서 발생하며 악성 가능성을 평가하는데 가장 중요한 요소는 병변의 위치이다. 추가적인 영상 소견과 임상 정보를 종합하여 효과적으로 진단 할 수 있다. 초음파검사는 표재성 기관인 음낭을 관찰하기 용이하며, 우수한 영상 품질을 바탕으로 병변의 유무뿐만 아니라 위치와 성상까지 확인 가능하다. 초음파검사로 감별이 어려울 경우에는 자기공명영상을 이용하여 지방, 출혈, 섬유화, 조영증강 등 추가적인 종양의 특징을 확인하는 것이 진단에 도움이 된다. 전산화단층촬영은 고환암의 병기결정이나 복강 내 미하강고환의 위치를 탐색하는데 유용하다. 본 종설에서는 고환 내외에서 발생하는 음낭 종양의 영상 소견을 살펴보고자 한다.

Splenogonadal fusion: a radiologic-pathologic correlation and review of the literature

We present the case of a 29-year-old male who presented to his General Practitioner with a left testicular lump. Scrotal ultrasound examination revealed 4 well-defined, homogenous, mildly hypoechoic extratesticular mass lesions. He was referred for an urgent urological opinion and underwent local excision. Histologic analysis revealed splenic tissue resulting in the diagnosis of splenogonadal fusion.

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.

MR imaging findings in perineal nodular induration ("cyclist´s nodule"): A case report

Perineal nodular induration (PNI) is a rare condition related to sports linked to the use of a saddle, mostly cycling, thought to be caused by the compression of the soft tissue between the saddle and the ischial tuberosity. We report a case of a 59-year-old amateur cyclist male who presented with 2 bilateral nodular perineal lesions that were evaluated with ultrasound and magnetic resonance imaging (MRI). MRI findings, along with the history of a strong cycling habit, led to the diagnosis of PNI, and a conservative management was adopted. MRI features of PNI are characteristic, and may provide the diagnosis in the proper clinical setting.

Sonographic appearance of angiomyofibroblastoma-like tumor of the scrotum

A variety of extratesticular tumors and tumor-like conditions can occur in the scrotum. Angiomyofibroblastoma is a rare, slow-growing, well-circumscribed mesenchymal tumor, found predominantly in women, and is even a more unusual occurrence in the male genital tract. We describe a case of a 64-year-old male presenting with a scrotal painless mass. On sonography, a well-circumscribed extratesticular mass was present. As no specific imaging findings were present, it was a surprise to learn that the subsequently excised mass proved to be an angiomyofibroblastoma-like tumor. To the best of our knowledge, the sonographic appearance of this tumor in the scrotum has been reported previously in only one case.

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.

Imaging of the scrotum: beyond sonography

The aim of this article is to describe the role of second-level imaging techniques after an initial ultrasonography evaluation in the assessment of scrotal diseases. While ultrasonography remains central as the primary imaging modality for the evaluation of pathologic conditions of the scrotum, the role of magnetic resonance imaging continues to evolve: it can actually be valuable as a problem-solving tool when sonographic findings are equivocal or inconclusive. Magnetic resonance imaging of the scrotum may provide accurate detection and characterization of scrotal diseases, well depicting the precise location of scrotal masses (intratesticular or extratesticular) and reliably characterizing benign conditions simulating neoplastic processes, thus preventing unnecessary radical surgery. Advanced magnetic resonance techniques, most of all diffusion weighted imaging and magnetic resonance spectroscopy, play in the meanwhile a more significant role in evaluating scrotal diseases.

TEACHING POINTS

• Multiparametric ultrasonography usually represents the initial imaging modality for approaching scrotal diseases. • MRI is well established as a problem-solving tool for inconclusive sonographic findings. • Advanced MRI techniques can be successfully applied in scrotal pathology assessment. • MRI is valuable in differentiating benign conditions from neoplastic processes. • CT plays a role in trauma assessment and cancer staging alongside PET/CT.

Scrotal sac leiomyoma: Case report of a rare benign scrotal mass

Leiomyomas are benign mesenchymal tumors, the overwhelming majority of which are located in the uterus. Rare cases arise in other organs, including the scrotum, pelvis, bladder, and spermatic cord. This report evaluates the case of a 37-year-old man with a history of prior left inguinal hernia repair, who presented with a painless right scrotal mass. He first noticed the mass approximately 1 year prior to his initial visit. Subsequent ultrasound of the scrotum demonstrated a 5-cm circumscribed, hypoechoic, mildly vascular extratesticular mass located within the right hemiscrotum. Based on the initial imaging, the differential diagnosis included lipoma, adenomatoid tumor, papillary cystadenoma, leiomyoma, fibrous pseudotumor, sarcoid granuloma, sarcoma (including liposarcoma, rhabdosarcoma, or leiomyosarcoma), lymphoma, and an extranumerary testis. The mass had circumscribed margins, suggesting an encapsulated lesion, and was completely separate from the testicle on ultrasound. Despite this, testicular malignancy was not entirely excluded as a diagnosis, although it was considered far less likely. The patient was definitively treated with surgical excision of the mass. Pathology of the surgical specimen confirmed diagnosis of leiomyoma, a rare scrotal mass.

Sonographic imaging of extra-testicular focal lesions: comparison of grey-scale, colour Doppler and contrast-enhanced ultrasound

Extra-testicular lesions are usually benign but present with nonspecific grey-scale sonography findings. This study assesses conventional sonographic characteristics in the differentiation of extra-testicular tumoural from inflammatory lesions and whether contrast-enhanced ultrasound has a role. A retrospective database analysis was performed. All patients were examined by experienced sonographers employing standard techniques combining grey-scale, colour Doppler sonography and contrast-enhanced ultrasound. Features recorded were: clinical symptoms, size, location, echogenicity, colour Doppler sonography and contrast-enhanced ultrasound enhancement. Vascularity on colour Doppler sonography and contrast-enhanced ultrasound was graded and compared. The lesions were classified as tumoural or inflammatory. The Chi-square test was used to analyse the sonographic patterns and kappa coefficient to measure the agreement between colour Doppler sonography and contrast-enhanced ultrasound. A total of 30 lesions were reviewed (median diameter 12 mm, range 5-80 mm, median age 52 years, range 18-86 years), including 13/30 tumoural and 17/30 inflammatory lesions. Lesions were hypoechoic (n = 12), isoechoic (n = 6), hyperechoic (n = 2) or mixed (n = 10). Grey-scale characteristics of tumoural vs. inflammatory lesions differed significantly (P = 0.026). On colour Doppler sonography, lesions had no vessels (n = 16), 2-3 vessels (n = 10) and ≥4 vessels (n = 4). On contrast-enhanced ultrasound, lesions showed no vascularity (n = 17), perfusion similar to testis (n = 7) and higher (n = 6). All abscesses identified (n = 9) showed no vascularity on both colour Doppler sonography and contrast-enhanced ultrasound. There was good agreement between these techniques in evaluating vascularity (κ = 0.719) and no significant difference between colour Doppler sonography and contrast-enhanced ultrasound of tumoural vs. inflammatory lesions (P > 0.05). The grey-scale appearances of extra-testicular lesions are essential for characterisation. Colour Doppler sonography and contrast-enhanced ultrasound findings are not useful in that respect. Contrast-enhanced ultrasound is excellent in establishing absence of vascularity.