The effect of phlorhizin on tumors in animals

Abstract

In 1914 Benedict and Lewis 1 reported the cure of malignant tumors in rats by the induction of glycosuria by phlorhizin. During the past few months similar experiments have been carried on in the laboratory of the Crocker Fund, using the same tumor—Buffalo rat sarcoma—and a progressively growing, highly malignant mouse carcinoma. In addition, seven mice bearing spontaneous tumors have been treated. The treated animals were kept on a diet of meat and lard, as in the experiments of Benedict and Lewis. The rats received subcutaneously 0.003 gram phlorhizin in olive oil, and the mice 0.001 gram, at two or three day intervals; and the collected urines were examined frequently at the end of the second or third day after injection, and found to give positive Fehling reaction.

Treatment was begun seventeen days after inoculation with the tumor, except in the cases of a few animals which were treated on the tenth day, and of a few which were first rendered diabetic and then inoculated. None of the tumors at the beginning of treatment had reached the size of the largest tumors reported cured by Benedict and Lewis.

Of the rats, there were alive twenty-four days after inoculation and seven days after beginning of treatment, 81 treated animals and 89 controls. Of the treated rats, 37 per cent. showed partial or subsequently complete absorption, while 58 per cent. of the controls had undergone spontaneous absorption. The largest tumor to disappear was among the controls and measured 26 × 14 mm. The largest growth noted occurred among the animals rendered diabetic before inoculation.

The laboratory stock of Buffalo rat sarcoma for the past fifteen months, representing over five hundred tumors, has showed 40 per cent. spontaneous absorption.