Nuclear grooves - How specific are they?

OBJECTIVE: To study the significance of nuclear grooves in thyroid and extr athyroid benign and malignant lesions. STUDY DESIGN: In this retrospective study, 26 cases were selected randomly, consisting of papillary carcinoma of the thyroid (7), papillary adenocarci noma (9), normal cervical smear (5) and benign bronchioalveolar lavage (BAL ) (5). In all cases hematoxylin and eosin- and Papanicolaou-stained smears were studied for nuclear grooves. RESULTS: Except for one case of papillary adenocarcinoma, nuclear grooves w ere discernible ill all cases. The highest number of nuclear grooves was se en iii normal cervical smears, followed by papillary carcinoma of the thyro id, papillary adenocarcinoma and BAL smears. CONCLUSION: The number of grooves did not correlate with either benign or m alignant conditions. These findings cast serious doubt about the diagnostic significance of nuclear grooves. Probably nuclear grooves are nonspecific findings and should be considered only in association with other diagnostic features.