Is the growth of breast carcinoma regulated by the axillary nodes?

The morphology of the axillary lymph nodes removed in connection with primary surgical treatment of 60 patients with infiltrating breast carcinoma is reported. The reactions in the nodes from patients presenting in the first 6 months of the year are shown to differ from those presenting later. The mean tumour diameters were also greater in the second period. The nodal changes at this time were characterized, in the node-negative, by germinal centre proliferation and a mixed sinus reaction or sinus catarrh. These reactions were less marked in node-positive cases. The morphological changes described indicate that immunological mechanisms are involved. It is suggested that they may regulate the growth of the primary. The possibility that they are subject to seasonal variation is discussed.