Cytologic comparison between growing and non-growing benign thyroid nodules evaluated using two different growth criteria

Aim: Thyroid nodules are frequent in the adult population. They are clinically important because of 5-10% risk of cancer. Thyroid fine needle aspiration biopsy is the first choice for diagnosing cancer in the nodule. It is suggested that biopsy-proven benign thyroid nodules should be followed up clinically and if they grow, re-biopsy should be performed. However, certain growth criteria have not been defined yet. In many studies using different growth criteria, significant risk for cancer in growing thyroid nodules was not demonstrated.Method: We retrospectively reviewed thyroid fine needle aspiration records of all patients seen in Dokuz Eylül University Hospital between January 2006 and June 2009. Growth follow-up of the nodules which had second thyroid fine needle aspiration biopsy were evaluted using two different growth criteria (at least 50% increase in nodule maximal diameter and at least 20% increase in nodule diameter with a minimum increase in two or more dimensions of at least two milimeter). Cytologic results were compared using two different criteria.Results: From a total of 4217 thyroid nodules, we evaluated the cytologic results of the benign thyroid nodüles which had follow up biyopsies. There is no significant difference in cytological results between the growing group (n:43) which have at least 50% increase in maximal nodule diameter and the non growing group (n:136)(p:1,00). Likewise, using the growth criteria of at least 20% increase in nodule diameter with a minimum increase in two or more dimensions of at least two milimeter, there was no significant difference in cytological results between growing (n:47) and non growing (n:70) benign thyroid nodüles(p:0,7).Conclusion: According to two different growth criteria used in our study, growth of a benign nodule is not an additional risk factor for cancer.Key words: Tyroid nodule, growth, thyroid fine needle aspiration biyopsy.