Two cases of schwannoma with marked cystic changes

We report two cases of schwannoma displaying marked cystic changes; one in the temporalis muscle and one in the submandibular space. The first patient, a 44-year-old male, presented after complaining of a swelling rapidly increasing in size in the left temporal region. Computed tomography (CT) indicated a low-density area surrounded by soft tissue. Magnetic resonance imaging (MRI) revealed signal hypointensity on T1 weighted imaging and strong signal hyperintensity on T2 weighted imaging. The extirpated tumour specimen measured 58 mm x 58 mm x 30 mm. Histopathological examination identified schwannoma, comprising spindle cell proliferation in a palisading pattern with obvious cystic changes. The second case involved a 46-year-old female who presented with swelling of the right submandibular region. Panoramic radiography and lateral oblique mandible projection, which were used together with conventional sialography of the submandibular gland, revealed the so-called "ball in hand" appearance of the submandibular gland, and contrast-enhanced CT identified a lesion of 30 mm diameter with a well-defined annular margin and homogeneous low-density near the tumour centre. Benign pleomorphic adenoma was suspected, but histopathological examination identified schwannoma, predominantly comprising Antoni B type tissue.