Magnetic resonance imaging findings for differential diagnosis of perianal plexiform schwannoma: Case report and review of the literature

Figure 1 Macrography of plexiform schwannoma. A: A multinodular cystic-solid mass of 5 cm × 3 cm is located on the right ischioanal fossa; B: The resected specimen shows a superficial vessel implanting into the tumour.

Figure 2 Coronal magnetic resonance imaging features. A: T1-weighted images demonstrate a well-defined subcutaneous mass located on the right ischioanal fossa with an isointense signal; B: T2-weighted images demonstrate that the mass is divided into multiple heterogeneously hyperintense nodules by intratumoral capsules; C: T1-weighted images after administration of intravenous contrast demonstrate homogeneously intense enhancement of the nodules, but with unenhanced intratumoral fibrous capsules.

Figure 3 Pathological results. A: Predominant Antoni A areas composed of spindle cells with palisading parallel rows are displayed by haematoxylin and eosin stain; B: Immunostain shows the tumour cells with diffuse immunoreactivity to S100 protein.