1. ¹Department of Urology, Christchurch Hospital, Christchurch, New Zealand
2. ²Department of Pathology and Molecular Medicine, Wellington School of Medicine and Health Sciences, University of Otago, Wellington, New Zealand
3. ³Department of Radiology, Christchurch Hospital, Christchurch, New Zealand
4. ⁴Department of Stomatology, University of Otago, Dunedin, New Zealand

Correspondence: Dr B Delahunt, MD, Department of Pathology and Molecular Medicine, Wellington School of Medicine and Health Sciences, PO Box 7343, Wellington South, New Zealand. E-mail bd@wnmeds.ac.nz

Received 24 February 2005; Revised 12 April 2005; Accepted 12 April 2005; Published online 27 May 2005.

Abstract

Cowden's syndrome is either familial or sporadic and is associated with the predominantly postpubertal development of a variety of cutaneous, stromal and visceral neoplasms. The syndrome is associated with mutations of the PTEN gene and is closely related to Bannayan's syndrome in which macrocephaly and benign tumors, especially lipomas and hemangiomas are pathognomic. In PTEN knockout mice testicular tumors have been reported and for this reason we felt it prudent to examine the testes of our patients with genetically proven Cowden's syndrome. Seven of eight patients who underwent testicular ultrasound were found to have diffuse bilateral hyperechoic lesions. Four patients consented to testicular biopsy and on histological examination multiple foci of adipocytes were found within the testicular interstitium, with no evidence of dysplasia or preclinical malignancy. Immunohistochemical assessment of adipocytes suggested a stromal derivation without evidence of metaplasia from Leydig cells. In one case there was focal atrophy of seminiferous tubules, while in two others there was nodular periorchitis of the tunica albuginea. Biochemical evaluation of testicular function (luteinizing hormone, follicle-stimulating hormone, testosterone, sex hormone binding globulin and free androgen index), prostate-specific antigen and testicular tumor markers were normal, while seminal fluid analysis showed only minor abnormalities. The high incidence of testicular lipomatosis in our adult subjects suggests this to be an important diagnostic criterion for Cowden's syndrome.