Abstract
Clinical observations show that the morphological pattern of carcinoma at its advancing margin is an indication of its growth potential and is related to the prognosis of the patient. As an experimental approach to the factors determining the growth pattern of carcinoma, three transplantable mouse tumors (a spontaneous CM mammary carcinoma, Bashford carcinoma 63 and Ehrlich ascites tumor) were observed for their growth in the subcutaneous tissue of untreated recipients and of those treated with typhoid vaccine, prednisolone or chloroquine. In the untreated animals, each of these tumors exhibited a specific pattern of the advancing margin, the tendency toward infiltrative growth being greatest in Ehrlich ascites tumor and least in the mammary carcinoma. But, common to these three tumors, the treatment with typhoid vaccine led to a less infiltrating tendency of the advancing margin, as evidenced by better defined tumor boundaries and development of thicker and denser peritumoral connective tissues, and those with prednisolone or chloroquine to a little more infiltrating tendency than in the control. This suggests that the morphological pattern of tumor growth is not fully inherent to each tumor but subject to considerable change according to the condition of the host, probably reflecting the activity of the reticuloendothelial system.
