Ancient Schwannoma of the Submandibular Gland in a Patient With Acromegaly: A Case Report

Ancient schwannoma is a rare degenerative variant of schwannoma. Its occurrence in the submandibular gland is exceptionally uncommon, and, to the best of our knowledge, its coexistence with acromegaly has not been previously documented. A 22-year-old male patient with a history of acromegaly presented with a long-standing, painless swelling in the left submandibular region. Magnetic resonance imaging (MRI) revealed a well-defined, heterogeneous T2-hyperintense lesion with cystic and calcific components within the left submandibular gland. The patient underwent complete surgical excision of the affected gland. Histopathological examination demonstrated a spindle-cell neoplasm with nuclear palisading, cystic degeneration, and dystrophic calcifications, consistent with ancient schwannoma. Immunohistochemistry showed diffuse, strong S-100 protein positivity and a low Ki-67 proliferation index (2-3%), confirming the benign nature of the tumor. This case describes a rare coexistence of a submandibular ancient schwannoma and acromegaly in a young patient. Although a causal relationship between excess growth hormone (GH) or insulin-like growth factor 1 (IGF-1) and schwannoma development cannot be established from a single case, this association is hypothesis-generating and highlights the need for careful head and neck evaluation in patients with endocrine disorders. The patient had an uneventful postoperative course, and no recurrence was observed at six-month follow-up.