ES02 SIGNIFICANCE OF LYMPH NODE MICROMETASTASES IN PAPILLARY THYROID CARCINOMA

Abstract

Purpose Management of nodal disease in papillary thyroid cancer (PTC) varies. The significance of micrometastases and their relationship to locoregional recurrence has not been well described. We set out to compare patients with micrometastatic nodal disease to those with macrometastases and those with no metastases. Our service follows a policy of routine central/recurrent nerve dissection and ipsilateral jugulocarotid node sampling for cases of PTC.Methodology One hundred and seventy patients who had surgery for PTC between January 1995 and December 2000 were included and split into three groups. Micrometastases (only micrometastatic disease), Macrometastases (any macrometastaic nodal involvement) and No metastases (absence of any nodal involvement). These three groups were compared for rates of locoregional disease recurrence and distant metastases.Results Contingency analysis showed that the Macrometastases group had a significantly higher rate of locoregional recurrence compared with both No metastases(Odds ratio 7.67, p < 0.0001) and Micrometastases groups (Odds ratio 9.212, p 0.0154). There was no difference between the No metastases and micrometastases groups (p 1.000), the p value suggesting the two groups were likely to be equivalent. Analysis revealed that distant disease was significantly more common in the Macrometastases group when compared to the No metastases group, (Odds ratio 25.09, p 0.0032)Conclusions Micrometastatic nodal disease associated with PTC does not lead to higher rates of locoregional recurrence or distant disease. These patients do not need completion neck dissection and have a low risk of locoregional recurrence.