Limitations of preoperative cytology for medullary thyroid cancer: Proposal for improved preoperative diagnosis for optimal initial medullary thyroid carcinoma specific surgery

Abstract

Preoperative diagnosis of medullary thyroid carcinoma (MTC) is often difficult, given the poor sensitivity of fine-needle aspiration (FNA) cytology for MTC. This study investigates this issue and presents recommendations for improving preoperative diagnostic paradigms in MTC cases. Histopathologically confirmed MTC patients with preoperative cytologic assessment of index nodules were enrolled. FNA diagnosis, final pathology, and surgery details were collected. Out of 71 patients, 49 (69%) were diagnosed by FNA as either definitive MTC (35, 49%) or suspected MTC (14, 20%) and 22 (31%) patients had no indication of MTC on FNA. In a tertiary-care setting, one-third of subjects had an FNA interpretation that did not suggest the possibility of MTC. The limitations of preoperative diagnosis are especially problematic for MTC as they can cause delayed or incomplete treatment. Additional testing is proposed to improve preoperative diagnosis and surgical care of MTC patients.