title: Could Tumor Size Be A Predictor for Papillary Thyroid Microcarcinoma: a Retrospective Cohort Study.
abstract: BACKGROUND
  Central lymph node metastasis(CLNM) is common in papillary thyroid microcarcinoma (PTMC). The aim of this study was to define the pathohistologic risk grading based on surgical outcomes.
  
  
  METHODS
  Statistical analysis was performed to figure out the optimal cut-off values of size in preoperative ultrasound images for defining the risk of CLNM in papillary thyroid microcarcinoma. Receiver operating characteristic curves (ROC) studies were carried out to determine the cutoff value(s) for the predictor(s). All the patients were divided into two groups according to the above size and the clinic-pathological and immunohistochemical parameters were compared to determine the significance of findings.
  
  
  RESULTS
  The optimal cut-off value of tumor size to predict the risk of CLNM in papillary thyroid microcarcinoma was 0.575 cm (area under the curve 0.721) according to the ROC curves. Significant differences were observed on the multifocality, extrathyroidal extension and central lymph node metastasis between two groups which were divided according to the tumor size by the cutoff values. Patients in two groups showed different positive rate and intensity of Ki67.
  
  
  CONCLUSIONS
  The size of PTMC in ultrasound images are helpful to predict the aggressiveness of the tumors, it could be an easy predictor for PTMC prognosis and assist us to choose treatment.
authors.affiliation: Department of General Surgery, Shanghai General Hospital of Nanjing Medical University, Nanjing Medical University, Shanghai, China E-mail : jimwsy@sina.com.
authors.forename: Min
authors.initials: M
authors.lastname: Wang
authors.forename: Wei-Dong
authors.initials: WD
authors.lastname: Wu
authors.forename: Gui-Ming
authors.initials: GM
authors.lastname: Chen
authors.forename: Sheng-Long
authors.initials: SL
authors.lastname: Chou
authors.forename: Xue-Ming
authors.initials: XM
authors.lastname: Dai
authors.forename: Jun-Ming
authors.initials: JM
authors.lastname: Xu
authors.forename: Zhi-Hai
authors.initials: ZH
authors.lastname: Peng
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor; D002291:Carcinoma, Papillary / Q000473:pathology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007124:Immunoenzyme Techniques; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D012372:ROC Curve; D012307:Risk Factors; D013964:Thyroid Neoplasms / Q000473:pathology*; D047368:Tumor Burden; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor