Case Presentation
A seventy-four year old female patient was examined at the outpatient section of the Maxillofacial Surgery Department of the University of Verona Medical Center for a submandibular lump on the right side. The lump was hard, mobile, and essentially asymptomatic. Other laterocervical lesions were not detectable at the time of palpation. The patient underwent both an ultrasonography of the neck, which detected a hypoechogenic lesion in the right submandibular gland, and a fine needle aspiration cytology (FNAC), which uncovered numerous epithelial cells exhibiting oval nuclei with moderate pleomorphism arranged in irregular, packed clusters, at times cruciform and papillary. There were also numerous cells with foamy cytoplasm and eccentric nuclei; siderophages and isolated cells with cytoplasmic mucin vacuoles were less numerous. While there were some signs of mitosis, there were none of necrosis. All of these findings were compatible with a diagnosis of a low grade mucoepidermoid carcinoma.
The patient underwent a full body computed tomography (CT) (Figure 2) which uncovered a 6 mm (approximately) focal hypodense lesion of the right submandibular gland. The patient subsequently underwent total en bloc lesion resection and emptying of the right suprahyoid muscle.The postoperative course was uneventful. The histological analysis led to the diagnosis of a secretory carcinoma. The lymph nodes were cancer-free. The fluorescence in situ hybridazation (FISH) analysis using specific probes mapping the neurotrophic receptor tyrosine kinase (NTRK) NTRK-1, NTRK2 and NTRK3 chromosomal fusion regions identified a chromosomal rearrangement of the NTRK3 gene and the absence of a chromosomal rearrangment of mastermind Like Transcriptional Coactivator 2 (MAML-2) and Ewing sarcoma region-1 (EWSR1) genes. Histochemical analysis uncovered S100, 5D3, RN7, RCK108 protein and vimentin positivity. Routine postoperative test results were cancer-free and now, 12 months after the operation, the patient continues to be cancer-free (Figure 1a-b-c).