Problems Encountered in the Diagnosis of Encapsulated Follicular Variant of Papillary Thyroid Carcinoma and the Morphological Diagnostic Criteria
The encapsulated follicular variant of papillary thyroid carcinoma constitutes the most common source of consultation material in thyroid pathology. We present our five consecutive cases to illustrate this issue. The diagnosis of the encapsulated follicular variant of papillary thyroid carcinoma is considerably controversial. These tumors are encapsulated neoplasms and have the nuclear features of papillary thyroid carcinoma. Although the criteria were described for the diagnosis, a considerable subjectivity is present among the pathologists. Therefore, the categories of "well differentiated carcinoma" and "well differentiated tumor of uncertain malignant potential" were included in the diagnostic spectrum of these neoplasms. Five consecutive cases with encapsulated and follicular growth pattern showing nodular thyroid lesion were included in the study. Morphological and clinical features of the cases were evaluated on the basis of preoperative cytology, postoperative pathology and clinical data. The age of the cases ranged from 34 to 55 years. Three of the cases were female, two cases were man. The size of the dominant tumoral nodules ranged from 1.5 to 4 cm. Three cases were diagnosed as encapsulated follicular variant of papillary thyroid carcinoma, while two cases were evaluated as well differentiated unknown malignant potential in the postoperative histopathologic study. We discuss the criteria of diagnosis, histological features and the diagnostic difficulties of these encapsulated and follicular growth pattern showing thyroid lesions with the accompanying literature.
Problems Encountered in the Diagnosis of Encapsulated Follicular Variant of Papillary Thyroid Carcinoma and the Morphological Diagnostic Criteria
The encapsulated follicular variant of papillary thyroid carcinoma constitutes the most common source of consultation material in thyroid pathology. We present our five consecutive cases to illustrate this issue. The diagnosis of the encapsulated follicular variant of papillary thyroid carcinoma is considerably controversial. These tumors are encapsulated neoplasms and have the nuclear features of papillary thyroid carcinoma. Although the criteria were described for the diagnosis, a considerable subjectivity is present among the pathologists. Therefore, the categories of "well differentiated carcinoma" and "well differentiated tumor of uncertain malignant potential" were included in the diagnostic spectrum of these neoplasms. Five consecutive cases with encapsulated and follicular growth pattern showing nodular thyroid lesion were included in the study. Morphological and clinical features of the cases were evaluated on the basis of preoperative cytology, postoperative pathology and clinical data. The age of the cases ranged from 34 to 55 years. Three of the cases were female, two cases were man. The size of the dominant tumoral nodules ranged from 1.5 to 4 cm. Three cases were diagnosed as encapsulated follicular variant of papillary thyroid carcinoma, while two cases were evaluated as well differentiated unknown malignant potential in the postoperative histopathologic study. We discuss the criteria of diagnosis, histological features and the diagnostic difficulties of these encapsulated and follicular growth pattern showing thyroid lesions with the accompanying literature.
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