Predictive factors of central lymph node metastasis in papillary thyroid carcinoma

PURPOSE: The aim of this study was to evaluate the correlation between central lymph node (CLN) metastasis and clinicopathologic characteristics of papillary thyroid cancer (PTC). In addition, we investigated the incidence and risk factors for contralateral CLN metastasis in unilateral PTC. This study suggests the appropriate surgical extent for CLN dissection. METHODS: A prospective study of 500 patients with PTC who underwent total thyroidectomy and prophylactic bilateral CLN dissection was conducted. RESULTS: Of 500 patients, 255 had CLN metastases. The rate of CLN metastasis was considerably higher in cases of younger patients ( or =1 cm) (P = 0.019; OR, 4.440) and with ipsilateral CLN metastasis (P = 0.047; OR, 2.613). CONCLUSION: Younger age (<45 years old) and maximal tumor size greater than 1 cm were independent risk factors for CLN metastasis. Maximal tumor size greater than 1 cm and presence of ipsilateral CLN macrometastasis were independent risk factors for contralateral CLN metastasis. Therefore, both CLN dissections should be considered for unilateral PTC with a maximal tumor size greater than 1 cm or presence of ipsilateral CLN macrometastasis.

Medullary and Papillary Thyroid Carcinoma as a Collision Tumor: Report of Five Cases / 대한내분비외과학회지

Medullary thyroid carcinoma and papillary thyroid carcinoma are different subtypes of thyroid carcinoma. The concomitant occurrence of medullary thyroid carcinoma and papillary thyroid carcinoma as a collision tumor is rare. We describe five cases of medullary and papillary thyroid carcinoma as a collision tumor. Four women and one man underwent thyroidectomy for treatment of thyroid cancer. Collision tumor was then detected by histopathologic finding. Genetic testing, point mutation of the BRAF gene or mutation of the RET gene was performed in three cases. However, only one case had point mutation of the BRAF gene. Exact diagnosis of this uncommon event is important because the strategies for treatment of papillary thyroid carcinoma and medullary thyroid carcinoma are different.