Factors predictive of papillary thyroid micro-carcinoma with bilateral involvement and central lymph node metastasis: a retrospective study

Abstract

BackgroundThe optimal resection extent for papillary thyroid microcarcinoma (PTMC) remains controversial. The objective of the study was to investigate risk factors of bilateral PTMC and central lymph node metastasis (CLNM) to guide surgical strategies for PTMC patients.MethodsWe retrospectively reviewed 211 PTMC patients who underwent total thyroidectomy (TT) and 122 clinical lymph node-negative (cN0) cases that underwent prophylactic central lymph node dissection (CLND) between 2010 and 2011. The frequency, pattern, and predictive factors for bilateral PTMC and CLNM in these patients were studied using univariate and multivariate analysis with respect to the following variables: age, gender, extrathyroidal extension (ETE), T stage, with Hashimoto thyroiditis (HT), tumor size and multifocality based on final pathology, and preoperative evaluation using ultrasonography (US).ResultsFifty-four of 211 (25.6%) patients had bilateral PTMC. In multivariate analysis, multifocality (P < 0.001, OR = 23.900) and tumor size ≥7 mm (P = 0.014, OR = 2.398) based on US were independent predictive factors for bilateral PTMC which was also independently associated with multifocality (P < 0.001, OR = 29.657) and tumor size ≥7 mm (P = 0.005, OR = 2.863) based on final pathology. Among 122 cN0 patients who underwent prophylactic CLND, we found 49.2% of patients had CLNM. CLNM was independently associated with men, age <50 years and tumor size ≥7 mm based on final pathology or preoperative US.ConclusionsTT should be considered for PTMC patients who are found multifocality and tumor size ≥7 mm based on preoperative US. CLND need be considered in cN0 patients who are men, aged <50 years or tumor size ≥7 mm based on preoperative US.

E-cadherin expression and cell proliferation in the primary tumor and metastatic lymph nodes of papillary thyroid microcarcinoma

“…Several studies reported that the presence of clinical lymph node metastasis in PTMC was one of the most important prognostic indicators, whereas others demonstrated that pathological lymph node metastasis identified following prophylactic dissection did not significantly affect patient prognosis. Pathological lymph node metastasis from PTMC was found in a range of 26-56% (15)(16)(17)(18)(19)(20). The reason(s) for the difference between clinical and pathological lymph node metastasis have not been fully elucidated.…”

Five Top Stories in Thyroid Pathology

“…Extrathyroidal extension and lymph node metastasis have been shown to be important predictors of locoregional recurrence in PTMC. 56,57 In some studies, 58-60 extrathyroidal extension has been reported in up to 52% of PTMCs. In our experience, extrathyroidal extension was seen relatively more commonly in microcarcinoma located at the periphery, involving the pseudocapsule of the thyroid gland.…”

“…In our experience, extrathyroidal extension was seen relatively more commonly in microcarcinoma located at the periphery, involving the pseudocapsule of the thyroid gland. Niemeier et al 61 56 …”

Papillary thyroid microcarcinoma

“…По данным литерату-ры, метастатическое поражение лимфоузлов было выявлено в 25-30% случаев [34,[43][44][45][46][47][48].…”

“…Несколько исследователей сообщили, что наличие метастазов в лимфатические узлы при микрокар-циномах является одним из наиболее важных про-гностических факторов, тогда как другие считают, что поражение лимфатических узлов существенно не влияет на прогноз пациента. Метастатическое пора-жение лимфоузлов при микрокарциномах было вы-явлено в 26-56% случаев [43][44][45][46][47][48].…”