To investigate the ultrasonographic and clinicopathological features of follicular thyroid cancer (FTC).

Seventeen patients diagnosed with FTC in the Ultrasonography Department of Nanjing Gaochun people′s Hospital between June 15, 2019 and December 31, 2022 were included to summarize the characteristics of ultrasonography, histopathology and gene testing results after fine needle aspiration cytology (FNAC) examination.

The lesions in 17 patients had an average length diameter of (31.23±15.44)mm. Uneven echo and no microcalcification were visible on ultrasound. The maximum diameter of the mass exceeded than 25 mm in 76.47% (13/17) of the patients, 88.24% (15/17) of the patients could see the blood signal in the mass, 70.59% (12/17) of the patients had sparse blood signal, and 82.35% (14/17) of the patients had no surrounding sound halo. The patients received a focal elastic imaging score of (2.53±0.76) points. Histopathological findings revealed that the mass had invaded the capsule and extended outside of the capsule in each case. Immunohistochemical analysis showed that all instances were positive for thyroid transcription factor 1 (TTF) and negative for calcitonin. Nine individuals had the post FNAC gene mutation detection, while the B-Raf proto-oncogene serine/threonine kinase (BRAF) mutation was negative. In these patients, 6 patients had telomerase reverse transcriptase (TERT) gene mutation detection, of which 5 were positive.

Postoperative pathological examination is considered the gold standard for the diagnosis of FTC. However, the combination of FNAC and TERT detection can enhance the preoperative diagnostic accuracy of FTC.