International Journal of Urology

(2002)

9,

602–603

Case Report

Blackwell Science, LtdOxford, UKIJU

International Journal of Urology0919-81722002 Blackwell Science Asia Pty Ltd

910October 2002521

Mesothelioma of testicular tunica vaginalisK Abe et al.

10.1046/j.0919-8172.2002.00521.xCase Report602603BEES SGML

Correspondence: Kazuhiro Abe

MD

, Jikei University Schoolof Medicine, 3-25-8 Nishishinbashi, Minato-ku, Tokyo 105-8461. Email: jk-uro@kd5.so-net.ne.jp

Received 12 December 2001; accepted April 2002.

Malignant mesothelioma of testicular tunica vaginalis

KAZUHIRO ABE,

1

NOBUKI KATO,

1

KENTA MIKI,

1

SATOSHI NIMURA,

2

MASAFUMI SUZUKI,

2

HIROSHI KIYOTA,

1

SHYOICHI ONODERA

1

AND YUKIHIKO OISHI

1

Departments of

1

Urology and

2

Pathology, Jikei University School of Medicine, Tokyo, Japan

Abstract

We report here a case with malignant mesothelioma of testicular tunica vaginalis. An 81-year-oldJapanese man with left hydrocele was referred for operation. When hydrocelectomy was performed,a thick wall of tunica vaginalis without malignancy was observed. Seven months after hydrocelec-tomy, a hard irregular mass was noticed in the left scrotum, therefore inguinal orchiectomy was per-formed. Pathologically, the mass showed severe atypia and mitosis. The diagnosis of malignantmesothelioma was made. He refused any adjuvant treatment and died 1 year later from multiplemetastases to the paraaortic lymph nodes and lumbar supine.

Key words

malignant mesothelioma, tunica vaginalis.

Introduction

Malignant mesothelioma of the testicular tunica vagina-lis is a rare disease. Asbestos exposure and trauma havebeen implicated as risk factors for the developmentof these tumors.

1

Accurate preoperative diagnosis ofmalignant mesothelioma of testicular tunica vaginalis isdifficult, which typically presented with a hydocele. Wereport here a patient with malignant mesothelioma oftesticular tunica vaginalis after hydrocelectomy.

Case report

A 81-year-old man with 30-year history of left hydro-cele was referred to our hospital. The patient had nohistory of asbestos exposure nor testicular trauma. Theinner wall of the cavity was normal in appearance, butthe testis was atrophic and the tunica vaginalis wasthickened, when hydrocelectomy was performed. Thecolor of hydrocele fluid was hemorrhagic, but cytology

was negative. Microscopically, marked fibroblasticgrowth was recognized in the wall of the tunica vagina-lis. Although mesothelial cells proliferations of tunicavaginalis were found occasionally, there was no evi-dence of mitosis nor atypical nuclei (Fig. 1). The patho-logic diagnosis was mesothelial proliferation due tochronic irritation. Seven months after hydrocelectomy, ahard irregular mass was noticed in the left scrotum. Weperformed inguinal radical orchiectomy. At operation,the tumor that surrounded the testis and epididymis wasremarkably thick, and it arose from the edge of tunicavaginalis. Macroscopically, the tumor consisted of hard,yellow nodules. Microscopic findings of the tumorshowed severe atypia and frequent mitoses indicatingmalignant mesothelioma (epithelial type) (Fig. 2). Thepatient refused all adjuvant treatment and died 1 yearlater from multiple metastases to the paraaortic lymphnodes and lumbar supine.

Discussion

Malignant mesothelioma of the testicular tunica vagina-lis is a rare tumor, frequently found in association witha hydrocele. Malignant mesothelioma originates fromserosal cells of the pleural, peritoneal, pericardial, andtunica vaginalis of testis. In Japan, among the 1785registered autopsy cases of malignant mesothelioma,only six cases (0.3%) originated from tunica vaginalis

Mesothelioma of testicular tunica vaginalis 603

of testis.

2

Plas

et al

. reviewed 74 cases of mesotheliomaof the tunica vaginalis testis from literature in 1998.

3

The etiology of mesothelioma is unknown, but asbestosexposure and trauma have been suggested as riskfactors for the development of these tumors. It wasreported that 34.2% of patients with mesothelioma ofthe tunica vaginalis have a positive history of asbestosexposure.

3

In our case, there was no past history ofasbestos exposure. Chronic irritation of a hydrocele maybe a predisposing factor of mesothelial hyperplasia andproliferation.

Although mesothelioma of the tunica vaginalis mostcommonly presents between the fifth and seventhdecade, 10% of the cases occurred in patients youngerthan 25 years.

3

There is no specific symptom ofmesothelioma of the tunica vaginalis. In many patients,preoperative diagnosis is a hydrocele. Due to a lack oftumor markers, accurate preoperative diagnosis is verydifficult. Haga

et al

. reported a case where the serumhyaluronic level was increased with tumor recurrence.

3

But the usefulness of the serum hyaluronic level as atumor marker is not established.

Mesothelioma is divided into two groups:

4

low-gradeor benign mesotheliomas and high-grade mesothelioma,according to the degree of nuclear atypia, frequencyof mitoses, and nuclear pleomorphism. In general,mesothelioma of the tunica vaginalis follows an aggres-sive course in older patients.

3

In this case, there was nomalignant finding in the tunica vaginalis when hydro-celectmy was performed. However, the specimens fromthe second operation and autopsy had malignantmesothelioma with a high degree of nuclear atypia,frequent mitoses, and tumor necrosis. Jones

et al

.emphasized the need for complete excision, even of

well-differentiated mesothelial tumors because of dis-tinguishing well-differentiated mesothelial neoplasmfrom mesothelial hyperplasia.

5

Effective adjuvant treatment is not established, soradical orchiectomy should be the first-line therapy.Retroperitoneum and inguinal lymphadenectomy wasperformed in some reported cases, but its usefulness iscontroversial. Mesothelioma of the tunica vaginalisprogresses to lymphatic or distant metastases. Plas

et al

.reported that the median survival of 73 patients was only23 months.

3

In summary, malignant mesothelioma of the tunicavaginalis is a rare neoplasm typically occurring in oldermen. We emphasize the need to suspect a mesotheliomain a patient with mesothelial hyperplasia of the hydro-cele. Therefore, postoperative attention should be givenwhen the inflammatory change of tunica vaginalis isrecognized in hydrocelectomy.

References

1 Antman K, Cohen S, Dimitrov NV. Malignant mesothe-lioma of the tunica vaginalis testis.

J. Clin. Oncol.

1984;

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: 447–51.2 Murai Y. Malignant mesothelioma in Japan: Analysis of

registered autopsy cases.

Arch. Environ. Health

2001;

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: 84–8.3 Plas E, Riedl CR, Pfluer H. Malignant mesothelioma of

the tunica vaginalis testis.

Cancer

1998;

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: 2437–46.4 Grove A, Jensen ML, Donna A. Mesotheliomas of the

tunica vaginalis testis and hernia sacs.

Virchow Arch. APathol. Anat. Histopathol.

1981;

415

: 283–92.5 Jones MA, Young RH, Scully RE. Malignant mesothe-

lioma of the tunica vaginalis.

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Fig. 1

Mesothelial cell proliferations of tunica vaginalisin the specimen from hydrocelectomy (H&E

¥

621).

Fig. 2

Diffuse malignant mesothelioma, epithelial type inthe specimen from the second operation (H&E

¥

621).