[The distribution of B-lymphocytes in lymphoepithelial tissues as well as in tumors of the neck-, nose-, and throat region derived from lymphoreticular and lymphoepithelial tissues (author's transl)].

B-Lymphocytes carrying IgG-, IgM,- and IgA-surface receptors were estimated by fluorescence microscopy in the palatine tonsil of 50 patients aged 3 to 18 years as well as in 44 patients with various types of malignant lymphoms and lymphoepithelial carcinomas. Hyperplastic tonsillartissue contains large numbers of B-cells with a marked variability in concentration (4-30% IgG-cells, medium 12,9%;6-36 IgM-cells, medium 23.4%;3-38% IgA cells, medium 20.8%). There appears to exist an age-dependent increase in IgM-cells and an increase in IgG-and IgA-cells in patients with numerous recurrent infections of the upper respiratory tract. Malignant lymphomas can be grouped into three main categories: Such with a predominance of one B-cell line (above 75-80% of one immunological cell type); these include primarily malignant lymphomas of the well differentiated lymphocytic type (IgM and IgA receptors). Secondly, such with a significant decrease in B-cells (below 10%) which include primarily malignant lymphomas of the poorly differentiated lymphocytic type. Thirdly, such with an increased B-cell content but with more than one cell line participating in cell proliferation. The latter ones comprise certain cases of Hodkin's lymphomas. Lymphoepithial carcinomas are charactersized by a significant decrease in total B-cell content, except for IgE- and IgD-cells which were not investigated. The results show that the immunologic classification of malignant lymphomas correlates only to a certain degree with the morphologic classification; i.e. the same morphologic type of tumor may possess different immunologic characteristics. Since the immunologic characteristics may reflect a certain functional potential of these tumors as well as probably a certain kind of immunologic incompetence prior to tumor development, it is suggested, that future morphologic investigations of malignant lymphomas and lymphoepithelial carcinomas are combined with immunologic classifications.