LAUSR

NTRK3 (although fusion of exon 4 of ETV6 with exon 14 of NTRK3 has been reported in salivary gland secretory carcinoma). In the few cases of secretory carcinoma of the thyroid in which the fusion breakpoints have been evaluated, the fusion has involved exon 4 of ETV6 and exon 14 of NTRK3. Thus, these findings indicate that even in the presence of an ETV6–NTRK3 fusion, other morphological features to differentiate PTC from secretory carcinoma must be considered; moreover, the clinical history must be reviewed to ensure that the patient does not have a salivary gland or breast primary. In summary, we describe a case of primary secretory carcinoma of the thyroid with increased proliferative activity and tumour necrosis. Differentiating secretory carcinoma from PTC is crucial both for prognostication and treatment purposes. Our patient is currently being treated with concurrent chemotherapy (taxol and carboplatin) and external beam radiation; however, therapy with a pan-Trk inhibitor could be considered in the future depending on the clinical course of disease.