Rationale: Low-grade intraductal carcinoma (LG-IC), is a rare malignant tumour of the salivary glands which has a very good prognosis and must be differentiated from the other types of salivary gland malignant tumours, which have a totally different behaviour and a worse prognosis.
Patient concerns: A case is presented of a 52-year-old woman who was first diagnosed and treated in another clinic in 2019 for an LG-IC in the left submandibular gland space. Two years later, she was admitted to our department with a new lesion, this time in the upper jaw lip on the left side, which also turned out to be LG-IC.
Diagnosis: Magnetic resonance imaging and positron emission tomography-computed tomography were performed in order to diagnose and adequately stage the disease prior to the therapeutic intervention.
Outcomes: A 6-month follow-up reveals no sign of recurrence.
Takeaway lessons: Literature on this rare histopathological entity, as well as the differential diagnosis with the other malignant lesions of the salivary glands and the frequency of metastasis, were reviewed.