The thermographic findings of 191 patients with Satges I-III breast cancer were retrospectively evaluated to determine the prognostic indicators of disease-free survival in both the whole study population and in each histological stage. The angioarchitecture of 75 breast cancer specimens was subsequently examined morphometrically using an immunohistochemical method, and was then compared with the extent of increase in the temperature at the tumor site. The extent of increase in the temperature was more closely related to the prognosis than was the thermal pattern. In stage II cancer (n=57), patients with lesions that showed a temperature increase > 1.5℃ had a poorer prognosis than the patients with hypothermic regions. (p<0.05). The range of skin temperature elevation at the tumor site correlated with the vascular changes in the skin above the tumor rather than with changes within or around the tumor in all of the patients. The increase in temperature above a tumor was concluded to be useful for assessing the prognosis and the grade of malignancy of breast cancer. The skin blood flow was also suggested to have the closest relationship with thermographic findings and the extent of the increase in blood flow to be a prognostic indicator for breast cancer.