STUDIES ON ENDOSCOPIC LOCAL INJECTION OF AN ANTICANCER AGENT INTO EXPERIMENTAL CANINE STOMACH CANCER

Abstract

In order to establish a topical chemotherapy against stomach cancer, the following experiments were performed.1. Adriamycin (ADM) solutions were injected through an endoscope into the submucosal space along the lesser curvature of normal canine stomachs. The dogs were sacrificed at various time intervals after initial injection and the concentration levels of ADM in the tissue were measured for fundamental study. ADM levels in the tissue at the gastric wall where the drug had been injected were one hundred times or more higher than in cases which had received ADM intravenously. At the regional lymph nodes along the lesser curvature, the ADM level was almost equal to that in the gastric wall where the drug had been injected.2. Stomach cancers were induced in 4 dogs by oral administration of N-ethyl-N'-nitro-N-nitrosoguanidine. One milliliter of ADM, 1 mg/ml was injected directly into 3 lesions in 2 dogs endoscopically. Total doses of ADM were 4 to 15 mg against each tumor. Two out of 3 tumors were almost completely reduced by this procedure, but minute cancer nests still remained histologically. One lesion among those treated was not reduced in size, but severe degeneration was observed histologically. No complication has occurred in these two dogs. One milliliter of ADM, 10 mg/ml was injected into 6 lesions in 2 dogs. Total doses were 2.5 to 10 mg against each tumor. Three lesions disappeared completely, and the other three lesions were markedly reduced in size. Three of 6 elevated cancers completely disappeared, but remnant cancers were observed in all of 3 depressed cancers treated by this therapy. Ulceration occurred in 5 out of 6 lesions. Perforation was observed in one of the five ulcerations. No lymph node metastasis was found in any of 4 dogs.It was indicated that endoscopic local injection of ADM against stomach cancer was effective to some extent in curing not only the primary lesion but also its lymph node metastases.