Submandibular schwannoma - A diagnostic dilemma: A rare case report

Schwannomas are benign tumors originating from Schwann cells, responsible for myelin sheath formation around peripheral nerves. Although primarily found in the head and neck, submandibular gland schwannomas are exceedingly rare.

This report details a 39-year-old male with progressively enlarging neck swelling over three months, associated with mild pain during eating. Physical examination revealed a firm, non-tender swelling, and radiological investigation through ultrasound showed a large, well-defined hypoechoic lesion in the right submandibular fossa. Fine-needle aspiration cytology initially suggested sialadenosis due to the presence of grape-like clusters of salivary gland acini in a hemorrhagic background. The patient underwent local excision of the tumor and submandibular gland, with histopathological examination confirming the diagnosis of schwannoma. The tumor exhibited characteristic Antoni A and B areas and Verocay bodies, with strong S100 positivity on immunohistochemistry.

This case underscores the challenge of diagnosing schwannomas in the submandibular region, where FNAC and ultrasonography may be inadequate.

MRI and histopathology are crucial for accurate diagnosis, differentiating schwannomas from other submandibular swellings such as pleomorphic adenomas.