A Diagnostic Approach to Paratesticular Lesions with Tubulopapillary Architecture: A Series of 16 Serous Borderline Tumors/Low-Grade Serous Carcinoma & 14 Well-Differentiated Papillary Mesothelial Tumors and Mesothelioma

Intratesticular Mullerian Serous Borderline Tumor With Microinvasion: A Rare Tumor and Review of the Literature

Ovarian-type (ie, Mullerian) epithelial tumors occurring in the testicular and paratesticular regions are exceptionally rare, with only a handful reported worldwide. Serous tumors are the most frequently encountered subtype among these rare tumors. The pathogenesis of these tumors within the testicular and paratesticular regions remains a subject of intrigue and debate, with various hypotheses attempting to explain their presence in the paratestis region, where most tumors occur. However, our understanding of the pathogenesis of intratesticular tumors is limited. To date, 11 known examples of intratesticular serous Mullerian tumors have been reported globally. In this report, we present an extraordinary tumor, an intratesticular Mullerian serous borderline tumor with foci of microinvasion, in a 38-year-old male patient. This tumor exhibits histological features similar to their ovarian counterparts and is confirmed through an immunohistochemical panel. Our report underscores the extreme rarity of these tumors, emphasizes the importance of heightened awareness among clinicians and pathologists, and provides valuable insights into their complex development and histogenesis. This contribution aims to enhance diagnostic precision and optimize therapeutic strategies for similar tumors.

Mesothelioma of the Tunica Vaginalis Testis: Diagnostic and Therapeutic Management. A Comprehensive Review, 1982-2024

BACKGROUND

Mesothelioma of the tunica vaginalis testis (MTVT) is an extremely rare and aggressive cancer. The diagnosis and management of MTVT is complex, and no standard treatment protocol is available.

METHODS

We conducted a systematic literature review from 1 January 1982 to 14 March 2024 using PubMed to collect all the available case reports and case series. A descriptive analysis of patient characteristics with clinical presentation, diagnostic work-up, therapeutic management, and past asbestos exposure was performed. Survival times of patients treated with different therapeutic approaches were evaluated.

RESULTS

Overall, 289 patients with MTVT were included in our analysis. The most common clinical presentations were scrotal/testicular swelling or mass (187 patients, 65%) and the presence of hydrocele (159, 55%). Imaging evaluation, mostly with ultrasonography or CT scan, was reported in two-thirds of cases. Radical surgery (216 patients, 75%) with orchiectomy and, in select cases, hemiscrotectomy and inguinal lymphadenectomy was the most frequent therapeutic approach. A minority of patients (49, 17%) received adjuvant therapy after surgery (radiotherapy, chemotherapy, or a combination of the two), with no evidence of survival improvement.

CONCLUSIONS

No standard guidelines for MTVT are available so far. Radical surgery following accurate radiological staging should be the mainstay of treatment. The role of adjuvant treatments remains undefined. Due to its rarity, MTVT should be treated in referral centers, and patients' data should be collected in a dedicated register in order to improve the knowledge of this exceedingly rare disease and establish optimal diagnostic and therapeutic management.

Local Cutaneous Scrotal Involvement of Paratesticular Mesothelioma

ABSTRACT

Paratesticular mesothelioma (malignant mesothelioma arising from the tunica vaginalis of the testis) represents a small proportion of mesothelial neoplasms, and cutaneous involvement by paratesticular mesothelioma is very rare. Cutaneous involvement can manifest as scrotal subcutaneous nodules from regional spread, distant metastasis, or direct extension through surgical scars. Mesothelioma has 3 histopathologic classifications that include epithelioid, biphasic, and sarcomatoid, which is rarely seen in paratesticular mesothelioma. Given the rarity of this condition, cutaneous mesothelioma may be misdiagnosed as histologic mimics, such as metastatic adenocarcinoma or adnexal neoplasms; thus, appropriate immunohistochemical workup and clinical correlation are required to make an accurate diagnosis. In this case, a 75-year-old man with a history of paratesticular mesothelioma, status postorchiectomy, presented with right-sided scrotal swelling, erythema, and subcutaneous nodules. These nodules were identified as local recurrence with cutaneous involvement by paratesticular mesothelioma on histopathologic examination. This case highlights the clinical and histopathologic features of this diagnosis and underscores the importance of dermatopathologists being aware of this condition to ensure accurate diagnosis.

Malignant Para-Testicular Mesothelioma: A Rare Presentation in the Tunica Vaginalis of an Elderly Male With No Prior Asbestos Exposure

Malignant mesothelioma of the tunica vaginalis is an extremely rare and aggressive tumor that is frequently encountered in elderly patients. The diagnosis of malignant mesothelioma of the tunica vaginalis poses a diagnostic challenge due to its infrequency and nonspecific clinical presentation. Histopathological examination and immunohistochemical staining are essential in differentiating this tumor from other para-testicular masses and establishing a definitive diagnosis. Early detection and comprehensive treatment planning are crucial for improving the prognosis and overall outcomes for patients with this rare malignancy. We present a report of malignant mesothelioma of the tunica vaginalis in a 78-year-old male patient with no history of asbestos exposure who presented with a large infiltrative left para-testicular mass. Histopathological examination revealed a biphasic proliferation composed of epithelioid and spindle cells with infiltrative features, foci of necrosis, and increased mitotic figures. Immunohistochemical staining exhibited positive staining for WT1, D2-40, and calretinin, supporting the mesothelial origin of the tumor. Notably, BerEP4 staining was negative, arguing against carcinoma. Immunostaining for keratin 5 was positive, supporting the mesothelial differentiation. The Ki67 proliferation index was high. The differential diagnosis included adenomatoid tumors, germ cell tumors, and pleomorphic sarcoma. We aim to discuss the clinical presentation, diagnostic approach, and therapeutic approaches of this rare entity.

Well-differentiated Papillary Mesothelial Tumour of the Tunica Vaginalis Testis - A Rare Lesion, but one Pathologists Should Know About Two Patient Reports and a Review of the Literature

Besides malignant mesothelioma, benign mesothelial neoplasms do exist in the tunica vaginalis testis. However, histological criteria remain controversial, thus leading to diagnostic uncertainty and difficulty in their classification according to their biological behavior. In recent years, molecular markers have emerged that aid in the differentiation of benign and malignant mesothelial proliferations throughout the body. Here, we present two middle-aged men with well-differentiated papillary mesothelial tumors and a review of the literature. By now, more than a year after surgery, one patient showed no recurrence of disease after partial or complete orchiectomy without further treatment, for the second no information is available. In conclusion, well-differentiated papillary mesothelial tumors represent rare lesions in the tunica vaginalis testis, but one pathologists should know about to prevent unnecessary treatment and suffering of patients.