Human regional tumour lymph nodes: alterations of micro-architecture and lymphocyte subpopulations.

Axillary lymph nodes draining mammary carcinoma showed an alteration of both micro-architectue and lymphocyte subpopulations. Lymph nodes with a normal or increased T and/or B lymphocyte compartment (assessed by histology) had a low incidence of nodal tumour spread, whilst hypocellularity of the T- or B-lymphocyte-dependent areas was associated with a significant increase in metastatic invasion. Tumour-draining lymph nodes, in particular the more proximal ones, were often enlarged, spherical and tense due to an increased cellular content, predominatly B lymphocytes and their various subsets. The increased number and percentage of B lymphocytes was associated with follicular hyperplasia and prominent germinal centres. Lymph nodes with a prominent paracortex tended to have a higher ratio of T to B lymphocytes than nodes with a hypocellular paracortical area, but in many instances both the T- and B-lymphocyte-dependent areas were increased. There was no correlation between a particular axillary-node lymphocyte subpopulation pattern (assessed by surface markers) and the size, degree of necrosis, inflammatory infiltrate or histologic type of breast carcinoma, or the presence of metastatic node invasion.