ROLE OF NUCLEAR GROOVES IN THE DIAGNOSIS OF PAPILLARY THYROID-CARCINOMA - A QUANTITATIVE ASSESSMENT ON FINE-NEEDLE ASPIRATION SMEARS

Thirty-four cases of papillary thyroid carcinoma and 69 control cases consisting of 17 follicular neoplasms, 5 Hurthle cell neoplasms, 7 med ullary carcinomas, 6 thyrotoxic goiters, 19 chronic lymphocytic thyroi ditis cases, 3 subacute thyroiditis cases and 12 colloid goiter cases were studied for nuclear grooves. Such grooves were seen in 100% of pa pillary carcinoma and in 75-100% of other thyroid disorders, but their number was strikingly higher in papillary carcinoma. A quantitative a ssessment for nuclear grooves was made based on counting 500 follicula r cells in hematoxylin and eosin (H&E)-stained and May-Grunwald-Giemsa (MGG)-stained smears. In H&E-stained smears of papillary carcinoma th e number of cells with nuclear grooves (227.3+/-99.96 SD) was signific antly higher as compared to other thyroid disorders (P <.01 to <.001). Eighty-eight percent of papillary carcinoma had nuclear grooves in gr eater than or equal to 20% tumor cells, whereas none of the other thyr oid diseases exceeded this level. In MGG-stained smears the number of cells with nuclear grooves (40.7+/-32.83 SD) was also significantly hi gher as compared to other thyroid disorders (P <.05 to <.001). Of papi llary carcinomas, 67.6% had >4% cells with nu clear grooves, whereas 0 -40% of other thyroid diseases exceeded this level. Nuclear grooves we re significantly higher in H&E-stained smears of papillary carcinoma a s compared to MGG-stained smears (P <.001). Based on this objective as sessment, nuclear grooves were a useful criterion in the diagnosis of papillary thyroid carcinoma in HG&E-stained smears but were not as rel iable in MGG-stained smears.