Clinical Analysis of 76 Cases of Differentiated Thyroid Isthmic Carcinoma after Operation

Objective: To investigate the clinicopathological features and surgical treatment of differentiated thyroid isthmus carcinoma. Methods: The clinical data of 76 patients with differentiated thyroid isthmus cancer diagnosed and operated in our hospital from January 2015 to January 2019 were retrospectively analyzed. Results: 16 cases of single focus, 60 cases with unilateral or bilateral multiple lesions, 76 patients. Bilateral thyroidectomy and bilateral CLN dissection were performed in 57 cases, unilateral thyroidectomy plus isthmus resection plus lateral total resection and bilateral central lymph node dissection in 17 cases. 2 cases underwent bilateral thyroidectomy plus bilateral CLN dissection plus unilateral neck lateral lymph node dissection. Lymph node metastasis occurred in 42 cases and lymph node metastasis in 40 cases, including 16 cases of unilateral central lymph node metastasis, 24 cases of bilateral central lymph node metastasis, and 2 cases with lateral cervical lymph node metastasis. 16 cases of single isthmus thyroid cancer, unilateral CLNM in 7 cases (43.75%), bilateral CLNM in 4 cases (25%), no metastasis in 5 cases (31.25%), and no lateral lymph node metastasis. Hypocalcemia occurred in 7 cases and temporary hoarseness occurred in 3 cases, which returned to normal within 3 - 6 months. All 76 patients were followed up. No permanent hypoparathyroidism, cervical lymph node recurrence, distant metastasis or death occurred in all patients. Conclusion: The treatment of differentiated thyroid isthmic carcinoma should be based on the pathological diagnosis, with bilateral thyroidectomy and bilateral CLN dissection as the main treatment. For patients with single focus, diameter ≤ 1 cm and low-risk group, if the above reasons are excluded, isthmus + unilateral gland resection and bilateral central lymph node dissection are feasible.