Well-differentiated papillary mesothelioma of tunica vaginalis testis of unknown malignant potential: Sonographic appearance

Our plain-English summary of Well-differentiated papillary mesothelioma of tunica vaginalis testis of unknown malignant potential: Sonographic appearance, by K.W.S. Ko, K.S. Tse, K.W. Shek, et al (Journal of Clinical Ultrasound, 2018).

The study

• Authors: K.W.S. Ko, K.S. Tse, K.W. Shek, M.N. Hau, S.H. Ting
• Journal: Journal of Clinical Ultrasound
• Published: 2018;46(5):364-367
• Type of article: Case report
• Cited by: 1 article, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Paratesticular mesothelioma is a rare differential diagnosis in the presence of scrotal hydrocele. A 17-year-old boy presented with a 3-year history of progressive hydrocele. Sonography revealed a large left paratesticular mass within the hydrocele. Serum tumor markers were negative. Left hydrocelectomy was performed and pathological analysis of the epididymal mass revealed a well-differentiated papillary mesothelioma. We discuss the sonographic and pathological findings of this rare neoplasm.

© 2017 Wiley Periodicals, Inc.

In plain English

This article is a case report from Queen Elizabeth Hospital, Hong Kong. It described one 17-year-old boy whose left side of the scrotum had grown larger, without pain, over 3 years. He reported no history of asbestos exposure. Ultrasound showed fluid around the left testis (a hydrocele) and a cauliflower-shaped mass of about 3 cm. The mass grew on a stalk from the left epididymis, with smaller deposits of up to 0.6 cm. The mass looked uniform on ultrasound, and blood flow was seen in both the stalk and the mass. Surgeons removed the fluid sac and the mass, and destroyed the many small nodules with diathermy. Under the microscope, the findings were consistent with well-differentiated papillary mesothelioma, which is usually regarded as benign. However, this tumor differed from conventional cases: in places it showed a more complex pattern, without clear invasion of surrounding tissue. The authors described it as being of uncertain malignant potential. Six months after surgery there was no sign of recurrence. The authors called the increased blood flow noteworthy and said future reports may show whether it helps diagnosis.

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), focused on ultrasound (sonographic) appearance
• Who was studied: One 17-year-old boy with a 3-year history of painless enlargement of the left hemiscrotum; the authors are from Queen Elizabeth Hospital, Hong Kong
• Exposure: No exposure was studied. The patient had no reported history of smoking, alcohol use, or asbestos exposure
• Main results:
  • Ultrasound showed a lobulated, cauliflower-shaped soft tissue mass arising from the left epididymal head, about 3 cm in size
  • Several additional deposits within the left scrotal sac measured up to 0.6 cm
  • The mass had homogeneous (uniform) echotexture on ultrasound
  • Color Doppler showed vascularity (blood flow) in both the stalk and the mass
  • Satellite nodules seen during surgery (more than 20) were ablated by diathermy
  • Pathology findings were consistent with well-differentiated papillary mesothelioma (WDPM), usually regarded as benign
  • The case differed from conventional WDPM in its focal complex architecture, without definite stromal invasion
  • The authors characterized the tumor as being of unknown (uncertain) malignant potential
  • The Ki67 proliferative index was low, up to approximately 4%, with no loss of BAP1
  • There was no evidence of recurrence 6 months after surgery. Follow-up was by serial ultrasound, with no chemotherapy or radiotherapy
• The authors' conclusion: The authors wrote that the ultrasound appearance overlapped with features described for malignant mesothelioma, but that the lesions were homogeneous. They stated that the increased vascularity is noteworthy and that future reports may help ascertain whether it is a useful diagnostic feature.

Topics

The National Library of Medicine indexes this study under subjects our site covers: Lung cancer, Mesothelioma.

Medical terms in this study, explained in our Lexicon: Well-Differentiated Papillary Mesothelioma, Tunica Vaginalis, Testicular Mesothelioma, Differential Diagnosis, Hydrocele, Paratesticular, Tumor Marker, Hydrocelectomy.

Related studies

• Malignant mesothelioma of the tunica vaginalis testis: unusual sonographic appearance — M.T. Wang, C.W. Mak, et al. (2005)
• Case Report of a Well-Differentiated Papillary Mesothelioma of the Tunica Vaginalis in an Undescended Testis With Review of Literature — P. Parcesepe, S. Sina, et al. (2016)
• Well differentiated (benign) papillary mesothelioma of the tunica vaginalis — R. Chetty (1992)
• Well-Differentiated Papillary Mesothelioma of the Tunica Vaginalis: Case Report and Systematic Review of Literature — W.K. Tan, M.Y. Tan, et al. (2016)
• Well-differentiated Papillary Mesothelioma of the Tunica Vaginalis — W.K. Tan, M.Y. Tan, et al. (2016)
• Papillary serous carcinoma of the tunica vaginalis testis — P. Becerra, M.A. Isaac, et al. (2000)

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