Adenoid Cystic Carcinoma Identified in Maxillary Sinus on Facial Pain Evaluation

An approximately 60-year-old female was referred for evaluation of non-spontaneous left-sided facial and infraorbital pain. A periapical radiograph had revealed a periapical radiolucent lesion on tooth #11, and the referring clinician was investigating whether it could be responsible for the pain. A CBCT was acquired for further evaluation, and the referring clinician noted soft tissue thickening in the left maxillary sinus, suspecting a mucus retention pseudocyst. Upon full-volume review, the radiologist determined that the soft tissue thickening was not consistent with a mucus retention pseudocyst. The thickening was causing erosion of the anterolateral and medial sinus walls with extension into the left nasal cavity, as well as demineralization of the left infraorbital canal and left orbital floor. The radiologist noted that these are aggressive findings not associated with benign pseudocysts and recommended the lesion be treated as likely malignant, with referral for further imaging and biopsy. The biopsy confirmed adenoid cystic carcinoma, an aggressive malignancy with a propensity for perineural spread. This case illustrates how soft tissue findings in the sinuses can appear routine but may harbor significant pathology that benefits from specialist radiologist review.