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Patterns of lymph node involvement in relation to hypotheses about the modes of spread of Hodgkin's disease

Two hypotheses have been put forward to account for the patterns of lymph node involvement observed in Hodgkin's disease. The Rosenberg‐Kaplan (R‐K) hypothesis suggests that spread of this disease is by tumor cell transport along contiguous lymphatic channels to adjacent lymph nodes, the cells travelling predominantly against the normal direction of lymph flow. The Smithers (S) hypothesis suggests that tumor induction may take place in one lymph node after another either through the influence of circulating initiators when localization depends on the susceptibility of different lymph node groups, or by tumor cell transport along lymphatics predominantly in the normal direction of lymph flow. These hypotheses have different implications for treatment and may be partially tested by comparing the predictions they make with the distributions of the disease observed. Such an analysis shows that the S hypothesis could account for the observations made.