[Experimental study on lymphatic spread in subcutaneously inoculated cancer with special reference to surgery and...

Two strains of ascitic tumor (AH109A, AH272 ) were subcutaneously injected into the foot of normally feed and protein deficient rats to study lymphatic spread of cancer. Survival and incidence of lymphatic metastases were determined following surgery for tumor-inoculated rats. In the normally fed rats, tumor cells were always demonstrated in popliteal lymph nodes 2 hours after AH109A inoculation. Sixty-seven percent survival was obtained in the control rats with amputation of the foot 2 hours after AH109A inoculation whereas 100% survival was obtained in the protein deficient rats with the similar treatment. Moreover 100% survival was achieved in both groups when foot amputation with popliteal lymphadenectomy was performed. On the other hand, no survival was obtained, and obvious distant lymph nodes metastases were observed in the rats in which the popliteal lymph node was excised prior to AH109A inoculation. Similar results were obtained after surgery in the AH272 inoculated rats. These findings suggest that the regional lymph nodes serve as a mechanical and functional barrier against the early spread of cancer cells within the lymphatic systems.