title: Clinicopathological features for predicting central and lateral lymph node metastasis in papillary thyroid microcarcinoma: Analysis of 66 cases that underwent central and lateral lymph node dissection.
abstract: Currently the surgical approach for papillary thyroid microcarcinoma (PTMC), particularly the range of lymph node dissection, remains controversial. The present study aims to evaluate the risk factors for central and lateral lymph node metastasis (CLNM and LLNM) for appropriate clinical decision of neck lymph node dissection in PTMC. A total of 66 cases of PTMC that underwent unilateral or bilateral lobectomy plus prophylactic cervical lymph node dissection were collected for clinicopathological evaluation, including age, gender, tumor size, subtypes, extrathyroidal invasion, multifocality, calcifications, loss of cellular polarity/cohesiveness (LOP/C) in the invasive front, CLNM and LLNM, and retrospectively analysis. Univariate analysis revealed that LOP/C was significantly associated with CLNM (P=0.001) and LLNM (P<0.0001). The male gender was a risk factor of CLNM (P=0.04), while the age <45 years, tumor size >0.5 cm and multifocality were high-risk factors of LLNM (P=0.022, 0.044 and 0.005, respectively). Multivariable analysis revealed that LOP/C was significantly associated with CLNM [P=0.007, odds ratio (OR)=7.765, 95% confidence interval (CI)=1.773-33.996] and LLNM [P=0.029, OR=5.717, 95% CI=1.190-27.470]. Both multivariable analysis and χ2test revealed that CLNM was another important high-risk factor of LLNM (P=0.021, OR=5.444, 95% CI=1.290-22.969, χ2=17.867, P<0.001). The present study revealed that prophylactic central lymph node dissection is essential for PTMC surgery and that prophylactic lateral lymph node dissection is recommend for patients with LOP/C and CLNM, which can be performed by intraoperative frozen section pathological examination. This must be considered discreetly in the case of patients with age <45 years, tumor size >0.5 cm and multifocal lesions.
authors.affiliation: Department of Head and Neck, Affiliated Hospital of Shandong Medical Sciences, Jinan, Shandong 250031, P.R. China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Tao
authors.affiliation: Department of Head and Neck, Affiliated Hospital of Shandong Medical Sciences, Jinan, Shandong 250031, P.R. China.
authors.forename: Chongjie
authors.initials: C
authors.lastname: Wang
authors.affiliation: Department of Head and Neck, Affiliated Hospital of Shandong Medical Sciences, Jinan, Shandong 250031, P.R. China.
authors.forename: Liye
authors.initials: L
authors.lastname: Li
authors.affiliation: Department of Head and Neck, Affiliated Hospital of Shandong Medical Sciences, Jinan, Shandong 250031, P.R. China.
authors.forename: Haijun
authors.initials: H
authors.lastname: Xing
authors.affiliation: Department of Head and Neck, Affiliated Hospital of Shandong Medical Sciences, Jinan, Shandong 250031, P.R. China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Bai
authors.affiliation: Department of Head and Neck, Affiliated Hospital of Shandong Medical Sciences, Jinan, Shandong 250031, P.R. China.
authors.forename: Bing
authors.initials: B
authors.lastname: Han
authors.affiliation: Department of Pathology, Qilu Hospital, Jinan, Shandong 250012, P.R. China.
authors.forename: Zhiyan
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Department of Pathology, Affiliated Hospital of Shandong Medical Sciences, Jinan, Shandong 250031, P.R. China.
authors.forename: Xiangshan
authors.initials: X
authors.lastname: Yang
authors.affiliation: Department of Head and Neck, Affiliated Hospital of Shandong Medical Sciences, Jinan, Shandong 250031, P.R. China.
authors.forename: Shourong
authors.initials: S
authors.lastname: Zhu
keywords: central/lateral lymph node metastasis; loss of cellular polarity/cohesiveness; papillary thyroid microcarcinoma; prophylactic central lymph node dissection; prophylactic lateral lymph node dissection