Endocrine Abstracts

JOINT1943

Introduction: Papillary thyroid carcinoma (PTC), originating from follicular epithelial cells, accounts for over 90% of thyroid cancers. In contrast, medullary thyroid carcinoma (MTC) arises from the parafollicular cells, and is characterized by the production of calcitonin. The simultaneous occurrence of PTC and MTC is a rare phenomenon and occurs in less than 1% of thyroid tumors. Therefore, it is crucial to conduct further research on the outcomes of concurrent PTC and MTC.

Case: A 72-year-old female had been monitored for 3 years due to nodular thyroid disease and subclinical hyperthyroidism. Hashimoto’s thyroiditis and Graves’ disease were excluded. Thyroid ultrasound There are hypoechoic nodules in the upper part of the thyroid (1.7 x 1.1 cm) and in the isthmus (0.7 cm). Fine-needle aspiration biopsy (FNAB) was performed. Thyroid scintigraphy with 99mTc "Cold" nodule in the thyroid gland. Cytological examination Not possible to rule out a tumor. Treatment In 2018, the patient underwent thyroidectomy and neck lymphadenectomy. Levothyroxine 100 mg/day for replacement maintains stable euthyroidism. Microscopic examination Papillary thyroid microcarcinoma pT1a / Medullary thyroid carcinoma pT1b. No mutations were found in KRAS codons 12/13, 61, 117, 146, or in NRAS codons 12/13, 59-61, 117, 146. Genetic consultation No known pathogenic or potentially pathogenic mutations in the RET gene, nor mutations of unknown clinical significance or likely benign sequence alterations were detected. Laboratory tests Pre-surgery calcitonin level was measured at 17.1 pmol/l. The following markers were monitored for the evaluation of recurrence post-surgery: CEA, calcitonin, thyroglobulin, and anti-Tg. All values remained within the reference range. Follow-up The patient undergoes annual oncological surveillance for thyroid carcinoma recurrence, including neck, chest, and abdomen imaging. No metastasis or recurrence has been observed. Neck ultrasound shows no pathological changes.

Conclusions: The concurrent occurrence of PTC and MTC in a single patient is exceptionally rare. Therefore, this case provides valuable insights into the management of simultaneous thyroid malignancies, emphasizing the importance of early detection and long-term follow-up to monitor for recurrence or metastasis.