[Ultrastructural classification of tumor cells (based on the example of human squamous cell lung cancer)]

Ultrastructural classification of tumour cells of human neoplasms is suggested on the basis of ultrastructural examination of 110 lung squamous cell carcinomas. All tumour cells may be subdivided into two groups: the tumour cells of the first group show the ultrastructural organ- and (or) tissue specific features; the tumour cells of the second group do not exhibit such features. The tumour cells of the 1st group may be represented by one, two or several different types. The tumour cells of both groups, depending on the intracellular organelles development, may belong to one of the following three types: 1) rich in organelles, 2) with moderate number of organelles and 3) poor in organelles. All the tumours on the whole should be divided into three varieties: the first variety--the number of the 1st group cells dominate; the second variety--the number of cells of the 1st and the 2nd group is the same; the third variety--the 2nd group cells dominate. The structural-functional alterations of tumour cells (change of nuclei and other organelles) should be fixed in every case. The proposed classification reflects the diagnostic needs of electron microscopy.