Scrotal extratesticular schwannoma: a case report and review of the literature

Abstract

Background: Schwannomas are tumours arising from Schwann cells, which sheath the peripheral nerves. Here, we report a rare case of left intrascrotal, extratesticular schwannoma. Although rare, scrotal localisation of schwannomas has been reported in male children, adult men, and elderly men. They are usually asymptomatic and are characterised by slow growth. Patients generally present with an intrascrotal mass that is not associated with pain or other clinical signs, and such cases are self-reported by most patients. Imaging modalities (such as ultrasonography, computed tomography, and magnetic resonance imaging) can be used to determine tumour size, exact localisation, and extension. However, the imaging findings of schwannoma are non-specific. Therefore, only complete surgical excision can result in diagnosis, based on histological and immunohistochemical analyses. If the tumour is not entirely removed, recurrences may develop, and, although malignant change is rare, this may occur, especially in patients with a long history of an untreated lesion. Thus, follow up examinations with clinical and imaging studies are recommended for scrotal schwannomas.

Case presentation: A 52-year-old man presented with a 3-year history of asymptomatic scrotal swelling. Physical examination revealed a palpable, painless, soft mass in the left hemiscrotum. After surgical removal of the mass, its histological features indicated schwannoma.

Conclusions: Schwannoma should be considered in cases of masses that are intrascrotal but extratesticular. Ultrasonography provides the best method of confirming the paratesticular localisation of the tumour, before surgical removal allows histopathological investigation and definitive diagnosis. Surgery is the standard therapeutic approach. To prevent recurrence, particular care should be taken to ensure complete excision. This case report includes a review of the literature on scrotal schwannomas.

Figure 1

Ultrasonography and colour Doppler examination of the schwannoma. The lesion appeared inhomogeneous, was partially hypoechogenic, and had poor hypervascularisation.

Figure 2

Elastographic investigation of the lesion. Quantitative elastography showed that the lesion had a low elastic modulus, as represented by the green area. After compression induced by the operator, there was no modification in the elastographic waves.

Figure 3

Intraoperative appearance of the lesion. The mass presented with some adhesions to the left testicle, but did not infiltrate the testicle.

Figure 4

Macroscopic examination and sectioning of the lesion. (A) Macroscopic examination after surgical removal showed a white mass that was soft and had a regular, translucent external surface. (B) After sectioning, the specimen was multinodular in appearance, with haemorrhagic areas.

Figure 5

Microscopic findings. (A) Proliferation was characterised by spindle elements with elongated hyperchromatic nuclei and poorly eosinophilic cytoplasm, separated by abundant oedematous fluid. These elements were occasionally arranged concentrically around vessels with thin walls (magnification × 4). (B) The cells show intense immunoreactivity for vimentin (magnification × 20) and (C) S-100 protein (magnification × 20).