Association between Different Variants of Papillary Thyroid Carcinoma and Risk-Group According to AMES (Age, Metastasis, Extent and Size) Classification System
Somboon Keelawat MD*, Ubon Poumsuk, Associate Degree of Science*
Affiliation : * Department of Pathology, Faculty of Medicine, Chulalongkorn University
Objective : To study the association between cell variants of papillary carcinoma and AMES (Age, Metastasis,
Extent and Size) risk classification.
Materials and Methods : One hundred and twenty-one cases of papillary thyroid carcinomas were subclassified
for cell type and risk-groups according to AMES classification system. Correlations between both variables
are evaluated.
Results : Among different cell variants of papillary carcinoma, solid cell pattern has the highest proportion of
high-risk tumor classified by the AMES criteria, comprising 75% followed by tall cell subtype with 33.3% of
high risk patients. Conventional papillary carcinoma has only 8.3% of high-risk group. Follicular and
encapsulated variants as well as microcarcinoma (< 1 cm) are all categorized as low-risk neoplasms.
Conclusion : The present study indicates that there is association between cell variants and AMES prognostic
index. The authors, therefore, emphasize the importance of cell variants in predicting the prognosis of papil-
lary carcinoma.
Keywords : Papillary thyroid carcinoma, Cell variants, AMES
