Case report--ancient schwannoma of the scrotum

Abstract

Background: Scrotal schwannoma is a rare neoplasm and poses a diagnostic challenge to urologists. This article describes a rare case of ancient scrotal schwannoma and reviews the current modality of investigation and treatment of this tumour.

Case report: A 28 year old man presented with a 3-month history of an asymptomatic scrotal swelling. Ultrasonography and computer topography revealed an intra-scrotal and extra-testicular mass without local invasion. Surgical excision was undertaken and histology was an ancient schwannoma of the scrotum.

Conclusion: Schwannoma is a benign encapsulating neoplasm with an overall low incidence, occurring mostly in the head and neck region and seldom in the scrotum. Histology shows two distinctive patterns, Antoni type A and B areas. Variations of schwannoma such as cellular, ancient, glandular and epithelioid are observed based on the appearances. Ancient schwannoma exhibits pleomorphism without mitosis as the result of cellular degeneration, which can lead to an erroneous diagnosis of malignancy. Imaging modalities are non-specific for schwannomas, but can define tumour size, site and extension. The mainstay treatment is complete excision, although local recurrence may occur in large and incompletely excised lesions. Malignant change is exceedingly rare.

Figure 1

Imaging of scrotal ancient schwannoma. a) Ultrasound image and b) CT image showing an intra-scrotal and extra-testicular mass in the mid-scrotal region [Capital red T – tumour, red t – testes].

Figure 2

Macroscopic appearance this scrotal ancient schwannoma. A white multinodular tumour with haemorrhagic areas.

Figure 3

Microscopic appearance of ancient schwannoma. a) spindle cells in an Antoni type A area; a red arrow indicates a large bizarre hyperchromatic nucleus b) Antoni B areas consisting of spindle cells within a loose myxoid matrix, c) occasional pleomorphic nuclei within Antoni A areas, and d) positive S100 immunohistochemical staining.