[Polarizing microscopic peculiarity of collagen in "minimal sclerosing carcinoma" of the thyroid].

Studies were conducted into 15 patients who had undergone surgery for various diseases, with twelve of them for established microcarcinoma as well as one each for advanced follicular carcinoma, diffuse sclerosing papillary carcinoma and fibroplastic thyroiditis. Differences in anisotropy of collagen were found to exist between tumour stroma and stroma removed from a tumour. These differences in double refraction of collagen are presumed to reflect specificity in organisation of the extracellular tumour matrix, different phases in formation of desmoplastic stroma as well as differences in invasiveness of the desmoplastic variants of thyroid microcarcinoma.