A New Risk Stratification Assessment To Lymph Node Metastasis Of Thyroid Papillary Carcinoma

PurposeCervical lymph node metastasis is a vital factor associated with local recurrence in papillary thyroid carcinoma (PTC). Tumor size is used in the staging of PTC as it represents the tumor load. This study compares two methods of tumor size assessment to predict tumor behavior in. the relationship between size and cervical node involvement for patients with PTC.MethodsOne thousand and eighty-four patients who underwent initial thyroid surgery and had a pathological diagnosis of PTC between 2012 and 2014 at The Second Affiliated Hospital Zhejiang University School of Medicine were included in this study. Cervical lymph node metastasis (LNM) risk was analyzed according to the clinicopathological features. For each patient with multifocal disease, two tumor size estimates were used: (1) the dominant focus size, and (2) the aggregate size which was calculated as the sum of the maximal diameter of all tumor foci.ResultsTwo hundred and ninety-four (27.1%) patients had multifocal cancer lesions and of them 49.0% had cervical LNM compared with 38.1% with unifocal disease (P=0.001). When tumor diameter of 1.0cm to 4.0cm performance LNM there was a significant difference (p=0.001); and when the tumor ≤1.0cm and >4.0cm, was not significantly different (≤1.0cm, p=0.188;> 4.0cm, p=1.000). When according to the total diameter of the tumor foci size classification, multifocality was not an independent risk factor for multifocal LNM’s (p=0.660); when compared to a single lesion foci of PTC and the overall diameter matched multifocal PTC, multifocal PTC not showed a higher risk of lymph node metastasis (p=0.188). Useing total diameter assess tumor size and using AJCC criteria from multifocal PTC,the found 199 cases of minor cancers (≤1cm) may strike out 96 cases (48.2%), one case of T3 tumors (> 4.0cm) increased to 7 examples.ConclusionMultifocality, together with aggregate tumor size is a more accurate predictor of node status and, by inference, tumor behavior in the relationship between tumor size and cervical node involvement.The use of aggregate dimension significantly increased the tumor size and reclassified significant numbers of multifocal PTCs at a more advanced T stage. This aggregate dimension took account of all tumor foci and predicts LNM risk at a proportion that was identical with size-matched, unifocal tumors.