The C-cell
hyperplasia of the thyroid gland is recognized as precursor to
medullary carcinoma, particularly in multiple endocrine
neoplasias, however it can be associated with hypercalcemic states and follicular tumours as well. The authors analysed 46 of their cases with Hashimoto's and/or
lymphocytic thyroiditis from the immunohistological point of view with the aim of determining to what extent is C-cell
hyperplasia associated with these pathological pictures. C-cell
hyperplasia was demonstrated on sections of intraoperative preparations with the immunoperoxidase method with anticalcitonin MoAb. Moderate, focal C-cell
hyperplasia was found in 17.4% (8 patients), extensive focal
hyperplasia similarly in 17.4% (8 patients). Diffuse C-cell
hyperplasia occurred in 1 case (2.2%). These results suggest the possibility that in the case of diffuse or more pronounced focal
hyperplasia the serum
calcitonin concentration of these patients is also elevated. Further clinical and pathological studies are needed to find out whether there is some pathogenetic relationship between
chronic lymphocytic thyroiditis and C-cell
hyperplasia or whether the finding is coincidental, and to establish what degree of C-cell
hyperplasia is associated with elevated serum
calcitonin levels. This relationship has been unknown until the present time, whereas it can be of great clinical significance, in part because of the changes in serum
calcitonin levels, in part for screening out the
MEN IIa type and working out the operating strategy.