Adenoid Cystic Carcinoma of the Lacrimal Gland With Late Mandibular Metastasis Presenting as an Intraoral Mass: A Case Report and Literature Review.

Adenoid cystic carcinoma (ACC) of the lacrimal gland is an uncommon but clinically aggressive malignancy, characterized by perineural invasion, local recurrence, and delayed distant metastasis. Mandibular metastasis is exceptionally rare. We report a 61-year-old man who presented with progressive right orbital swelling, proptosis, and visual loss. Imaging demonstrated a destructive lacrimal gland mass with temporal bone involvement. The patient underwent surgical debulking followed by radiotherapy, with subsequent local recurrence. Two years later, he developed a painless right posterior mandibular swelling presenting as an intraoral mass near a recent dental extraction site. Imaging and histopathology confirmed metastatic ACC. Despite systemic chemotherapy and additional radiotherapy, the lesion progressed. This case underscores the need for long-term surveillance in lacrimal gland ACC and careful assessment of new oral or maxillofacial lesions, as metastatic disease may mimic benign odontogenic conditions and present years after initial treatment.