The 12 specimens of histologically proven cystic papillary carcinoma diagnosed by fnab as atypical exhibited similar nuclear features i e nuclear enlargement fine chromatin and nuclear grooves as observed in many of the benign thyroid cysts. Despite the conspicuous absence of some classic features of papillary rcc the diagnosis of low grade papillary rcc was not. 12 nuclear grooves one of the most touted features of papillary rcc were common in only 2 of our papillary rcc cases they were rare in 6 and altogether absent in 7 cases but were seen in 25 of other tumors.
Although formation of incis is linked to nuclear grooves they seldom exist together. Intranuclear cytoplasmic inclusion inci and nuclear grooves in fine needle aspiration fna smears of papillary thyroid carcinoma ptc represent cytoplasmic invaginations into the nucleus. It is also the predominant cancer type in children with thyroid cancer and in patients with thyroid cancer who have had previous radiation to the head.
It occurs more frequently in women and presents in the 20 55 year age group. Papillary thyroid cancer or papillary thyroid carcinoma is the most common type of thyroid cancer representing 75 percent to 85 percent of all thyroid cancer cases. Nuclear grooves and inclusions are important diagnostic features of cancer although intranuclear inclusions are seen in normal epithelial cells 1 in fact nuclear inclusions are commonly found in some benign and malignant tumors including papillary thyroid carcinoma hepatocellular carcinoma melanoma paraganglioma meningioma and pituitary adenoma 2 it is speculated that the nuclear.
Nuclear grooves were also observed in two of the 113 non ptc cases 1 8 both of which were colloid nodules one with extensive hurthle cell change. Among the ptc cases grooved nuclei were found in all 11 100 intranuclear inclusions in nine 82 papillary fragments in seven 64 and psammoma bodies in two 18. Ovarian tumors including brenner tumors adult granulosa cell tumors and transitional cell tumors.
It is a characteristic feature of papillary thyroid carcinoma but has also been seen in other types of thyroid neoplasms as well as in non neoplastic thyroid lesions. It can be present in. A nuclear groove is an invagination of the nuclear envelope in the longitudinal axis.
A quantitative assessment for nuclear grooves was made based on counting 500 follicular cells in hematoxylin and eosin h e stained and may grünwald giemsa mgg stained smears. Such grooves were seen in 100 of papillary carcinoma and in 75 100 of other thyroid disorders but their number was strikingly higher in papillary carcinoma.
