A method for evaluating regional effects of cytotoxic drugs on proliferating cells in lymph nodes.

Tin powder, injected into both hindfeet of rats, caused intense proliferation of the plasma cell series in the draining lymph nodes. The hyperplasia was evaluated by weight and by histology of the nodes. This simple, rapidly executed model was used to evaluate the delivery of locally injected cytotoxic drugs to regional lymph nodes. Inhibition of hyperplasia was compared to both internal controls (contralateral node) and external controls. Mitoxantrone and methotrexate, injected locally according to certain doses and schedules, were effective in reducing the lymph node hyperplasia with little or no systemic effects. This model should assist in the evaluation of drugs, schedules, and adjuvants that might be used in the regional treatment of lymph node hyperplasia or metastic neoplasia.