The significance of nuclear diameter in the biologic behavior of thyroid carcinomas: A retrospective study of 127 cases

The relationship between nuclear diameter and biologic behavior was studied in 127 cases of thyroid carcinoma. Using a sonic digitizer coupled to a minicomputer, nuclear diameters of 200 randomly selected cancer cells from each case (hematoxylineosin-stained paraffin sections) projected at x400 magnification were traced and averaged. A total of 25,400 measurements were made. The nuclear diameters varied from 4.7 to 13.1 μm. By analysis of variance, the nuclear diameters were significantly different ( p =0.0007) among the four types of thyroid cancers, being largest in the undifferentiated cancers (8.7±0.8 μm) and smallest in the medullary cancers (6.6±0.1 μm). Nuclear diameter was also significantly correlated with degree of tumor differentiation ( p =0.002), maximal tumor diameter ( p =0.03), mitotic rate ( p =0.002), and 5-year survival ( p p =0.04). No significant correlations were seen between nuclear diameter and duration of disease, sex, or age of the patient.