Malignant mesothelioma of the tunica vaginalis testis: A case report

Our plain-English summary of Malignant mesothelioma of the tunica vaginalis testis: A case report, by Z. Liu, A. Han, S. Li, et al (Oncology Letters, 2026).

The study

• Authors: Z. Liu, A. Han, S. Li, J. Zhang, Y. Guo, C. Sun
• Journal: Oncology Letters
• Published: 2026;32(5):517
• Type of article: Case report
• Read it: PubMed · Publisher · Free full text

Abstract

The aim of the present study was to report a case of malignant mesothelioma of the tunica vaginalis testis (MMTVT) and to discuss clinicopathological features and therapeutic dilemmas to provide references for individualized management of similar cases. The case of a 57-year-old male patient with MMTVT, admitted in February 2025, was retrospectively analyzed. The patient presented with left scrotal pain and had a 30-year history of vasectomy. Scrotal ultrasound, testicular MRI and serum tumor marker analyses were performed, followed by local resection of the left tunica vaginalis tumor under spinal anesthesia. Diagnosis was confirmed using postoperative pathology and immunohistochemistry. After comprehensive counseling on recurrence and metastasis risks, the patient and their family declined radical orchiectomy and adjuvant chemotherapy, and close surveillance was instituted. Postoperative pathology confirmed biphasic MMTVT. Immunohistochemistry demonstrated positive mesothelial biomarkers: D2-40(+), calretinin (focal+) and cytokeratin 5/6 (focal weak+). Ki-67 was ~10%, with wild-type p53 expression. The tumor was completely excised with negative margins. No recurrence or metastasis was observed at the 12-month follow-up. This case, presenting with scrotal pain as initial presentation, further highlights the clinical heterogeneity of MMTVT. The remote vasectomy history, which is rarely documented, raises an etiological question for investigation. The biphasic subtype with low Ki-67 suggests that prognostic evaluation requires integrating histological subtype and molecular biomarkers. The 12-month recurrence-free survival time following isolated local excision provides preliminary evidence for organ-sparing management, although long-term outcomes require continued surveillance.

Copyright: © 2026 Liu et al.

In plain English

This article was a case report about one 57-year-old man treated at Shijiazhuang People's Hospital in China in February 2025 for malignant mesothelioma of the tunica vaginalis testis, a rare cancer of the lining around the testis. The patient came in with left scrotal pain and discomfort lasting more than 20 days. The patient denied any long-term exposure to asbestos or asbestos products and had had a vasectomy 30 years earlier. Surgeons removed a mass of about 1.5 x 2.0 x 1.0 cm above the left testis. Pathology confirmed a malignant biphasic mesothelioma with a Ki-67 index of about 10%. The tumor was completely removed with negative margins. The patient declined a second operation (radical orchiectomy) and declined adjuvant chemotherapy, so close follow-up was arranged. As of February 2026 there were no signs of recurrence or spread. The authors noted these limits: the report covers a single case, two diagnostic stains (BAP1 and WT-1) were not done, and follow-up lasted only 12 months. The authors concluded that a possible link between prior vasectomy and this cancer deserves attention but needs confirmation in larger case series.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: case report (single patient, retrospectively analyzed)
• Who was studied: One 57-year-old male patient admitted to Shijiazhuang People's Hospital Affiliated to Hebei Medical University, Shijiazhuang, China, in February 2025
• Exposure: No asbestos exposure was reported. The patient denied long-term exposure to asbestos or asbestos products. The authors discussed the patient's vasectomy 30 years earlier as an unproven possible clue.
• Main results:
  • The patient presented with left scrotal pain and discomfort of more than 20 days and had a vasectomy 30 years earlier.
  • At surgery, a mass of about 1.5x2.0x1.0 cm was found above the left testis and removed.
  • Pathology confirmed a malignant biphasic mesothelioma arising from the mesothelium of the left tunica vaginalis testis.
  • On immunohistochemistry, p53 showed a wild-type pattern, Bcl-2 was negative and the Ki-67 index was about 10%.
  • The tumor was completely resected with negative margins.
  • The patient declined a second surgical procedure (radical orchiectomy) and also declined adjuvant chemotherapy.
  • As of February 2026 (12 months of follow-up), there were no signs of local recurrence or distant metastasis.
• The authors' conclusion: The authors concluded that the possible association between prior vasectomy and this cancer deserves attention but requires validation in larger case series. They also stated that clinicians should remain alert to this cancer in patients presenting with scrotal pain.
• Limitations the authors state:
  • As a single-case report, its conclusions have limited generalizability.
  • BAP1 and WT-1 immunohistochemical stains were not performed.
  • Follow-up lasted only 12 months, so the long-term outcome is unclear.
  • The patient's refusal of standard treatment limits the reliability of the treatment conclusions. The authors stated that the good short-term outcome should not be taken as justification for omitting radical surgery.
  • Because the study was retrospective, the exact antibody clone numbers and suppliers could not be fully verified.

Topics

Medical terms in this study, explained in our Lexicon: Mesothelioma, Tunica Vaginalis, Ultrasound, Tumor Marker, Pathology, Immunohistochemistry, Metastasis, Orchiectomy.

Related studies

• Malignant mesothelioma of the tunica vaginalis testis: report of first case with preoperative diagnosis — L. Japko, A.A. Horta, et al. (1982)
• Malignant mesothelioma of the tunica vaginalis testis — K. Antman, S. Cohen, et al. (1984)
• Epidemiology of mesothelioma of the pericardium and tunica vaginalis testis — G. Mezei, E.T. Chang, et al. (2017)
• Malignant mesothelioma of the tunica vaginalis testis: diagnostic studies and differential diagnosis — S.S. Chekol, C.C. Sun (2012)
• Malignant mesothelioma of the tunica vaginalis testis: a rare case and review of literature — M. Drevinskaite, A. Patasius, et al. (2020)
• Malignant mesothelioma of tunica vaginalis testis — G. Tyagi, C.S. Munn, et al. (1989)

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