Surgical chemotherapy against lymph node metastases: an experimental study.

Accompanying surgical resection of the primary tumor is removal of its drainage lymph nodes. However, all of the minute regional lymph nodes cannot be identified and some may be left behind. If a certain anticancer agent in the form of an emulsion is injected topically into the lymph nodes, it may suppress the lymphatic metastases. Domestic rabbits were used as experimental animals, because transplantable VX2 tumors are available. The vermiform appendix was selected as the transplantation site because of its rich supply of lymph follicles, simulating lymph nodes histologically, and because the path of lymph drainage is very simple. The drainage lymph node, which is located at the root of the appendix, was selected for study. The rate of transfer of bleomycin into lymph nodes and of its sustained release from the nodes was extremely enhanced by the use of a sphere-in-oil-type emulsion--more than two times higher than in the use of a W/O emulsion. Although prolongation of survival time did not take place in animals receiving the bleomycin solution topically or intravenously, five of the seven rabbits receiving the local administration of bleomycin as a sphere-in-oil or a water-in-oil emulsion, between which differences were not found in tumor effects, survived with complete reduction of the lymph node metastases.