Rationale: Oral liposarcoma is an extremely rare lesion that is often clinically misdiagnosed as a benign lesion because of its asymptomatic and indolent clinical course. we report a case of atypical lipomatous tumor/well-differentiated liposarcoma (ALT/WDL) of buccal mucosa, provisionally diagnosed as lipoma.
Patient concerns: A 97-year-old female was referred to dentistry and oral surgery department with an asymptomatic mass on the right buccal mucosa which had been present for an unknown period of time.
Diagnosis: Magnetic resonance imaging demonstrated a well-circumscribed lesion at the right buccal mucosa, and a lipoma was suspected.
Interventions: Surgical removal was performed, and a diagnosis of ALT/WDL was made. She and her family refused additional treatment due to her age.
Outcomes: At the 10 months follow-up, the patient remained free of disease.
Lessons: The indolent clinical course and small size of oral liposarcoma can lead to provisional clinical diagnosis of benign lesion.