Abstract
Objective : The aim of this report is to establish an algorithm for cytological diagnosis of thyroid follicular lesions and to propose a new reporting system.
Study Design : We reviewed the preoperative fine needle aspiration cytology findings of 78 cases of follicular adenoma and 40 cases of follicular carcinoma resected in Kuma Hospital from January to December 2011.
Results : The incidences of overlapping follicles, three-dimensional small follicles accounting for more than 50% of the small ones, trabecular pattern, nuclei more than twice in size than that of the neutrophils and hyperchromasia were statistically significantly higher in the follicular carcinoma cases than in the follicular adenoma cases. Of the follicular carcinoma cases, 32.0% showed one of the above findings, 60.9% showed two, 42.9% showed three, 62.5% showed four and 100% showed all five of the above findings.
Conclusion : We have proposed an algorithm for cytological diagnosis of thyroid follicular lesions and a reporting system. As it is cytologically difficult to distinguish, between follicular adenoma and follicular carcinoma, we think that the goal in the reporting of thyroid follicular lesions is not the histological diagnosis, but the recommendation for clinical management.
