Analysis of prognostic factors for the indication of central lymphadenectomy in papillary thyroid carcinomas.

ABSTRACT

BACKGROUND: In this study we examined whether it was possible following preoperative parameters statistically significant correlation with the presence of metastatic lymph nodes in the papillary thyroid carcinoma. We conducted a retrospective study in a group of patients with a preoperative diagnosis of papillary carcinoma who underwent total thyroidectomy associated with routine lymphadenectomy of the central compartment (level VI). PATIENTS AND METHODS: The study group consisted of patients whose definitive histological lymph node examination was positive for metastasis (N1), and the control group comprised patients found negative for metastasis (N0). RESULTS: Tumour diameter had a significance at 10% level [Pr(>|z|) 0.056], thus indicating that increased tumour size results in a higher probability of being in group N1. The logistic regression revealed that variables with a significance at 5% level for the presence of metastatic lymph nodes in the central compartment (N1) were sex [Pr(>|z|) 0.019], overall patient age [Pr(>|z|) 0.012] and age >45 [Pr(>|z|) 0.022]. We performed a statistical analysis with the association of three preoperative variables (presence of ultrasound-revealed microcalcifications, presence of solid hypoechogenic nodule and type III vascularisation on echocolour-Doppler); this was found to result in a highly significant probability of entering into group N1. CONCLUSIONS: We found variables statistically significant for the presence of metastatic central compartment lymph nodes, including female sex, age >45 yrs and tumour diameter >1.5 cm. The association of papillary carcinoma with microcalcifications, solid hypoechogenic nodule structure and type III vascularisation on echocolour-Doppler also resulted in a statistically significant increase in the probability of positive level VI lymph nodes.