An 80-year-old woman comes to the clinic with a painless left submandibular tumour that has been present for 2 months and has experienced progressive growth and increased consistency. It is not accompanied by constitutional syndrome. The patient's only history was renal lithiasis and arterial hypertension. Physical examination revealed a left submandibular mass approximately 4 cm in diameter, hard in consistency, adherent to deep planes, which did not cause pain on palpation. There were no alterations in cervical mobility or facial expression. In the intraoral examination there was no inflammation of the floor of the mouth or Wharton's canal. An ultrasound-guided fine needle aspiration puncture-fine needle aspiration (FNA) was performed, which was reported as a carcinoma of undetermined nature. An MRI scan was requested and the report was compatible with a heterogeneous left submaxillary mass, with internal necrosis, measuring 3 × 4 × 3 cm, which had imprinted on the floor of the mouth, with no conclusive signs of infiltration of the supra-hyoid musculature and which respected the mandibular bone cortex.

With the diagnosis of malignant tumour of the submaxillary gland, a type III left functional cervical dissection was performed, including the hypoglossal nerve, the digastric muscle and the marginal branch of the left facial nerve, with a reaming of the left mandibular medial aspect.
Histological analysis of the specimen shows a neoplastic proliferation with infiltrative borders, growing in nests and cords, consisting of cells with large cytoplasm and plasmacytoid and epithelioid morphology. The nuclei are atypical with moderate pleomorphism, prominent nucleolus and 11 mitoses/10 high magnification fields. The cells are arranged within a hyalinised stroma. Extensive areas of necrosis and foci of squamous differentiation are seen. No ductal structures are seen. The immunohistochemical study shows that the neoplastic cells are positive for CKAE1/AE3, actin, calponin, p63, S-100 protein and GFAP, and negative for CEA. The proliferative index (Ki67) is 25%. The tumour is completely resected and the distance to the nearest resection margin is less than 1 mm. The lymph nodes are negative for malignancy. This report is compatible with the diagnosis of myoepithelial carcinoma of the submaxillary gland pT3-N0, MX.
Following a multidisciplinary consensus, postoperative radiotherapy was decided. The total dose of radiotherapy received was 60 Gy, divided into 30 sessions.
The patient is being followed up in outpatient clinics 3 years after the surgery and, after serial control MRI and CT scans, no signs of tumour recurrence or metastasis were observed.