We examined the density of tumor enhancement onintravenous digital subtraction angiography (IV-DSA) in patients withbreast cancer in relation to disease-free survival. Thesubjects of the present study consisted of 103patients with invasive ductal carcinoma measuring 5 cmor less treated from July 1988 to September1993. In the 103 patients, 15 had distantmetastasis. The region of interest was set inthe areas enhanced by IV-DSA of the breast.The maximum density (MAX) was calculated by thetime-density curve. When the patients were divided accordingto three classes of MAX, i.e., 0–5.0 pixels(group A, n=23), 5.1–9.0 pixels (groupB, n=50), 9.1 pixels or more(group C, n=30), disease-free survival washighest in group A followed by group Band C, respectively. The disease-free survival rate ingroup C was significantly lower than that ofgroup A or B (p < 0.05). Thus,high values of MAX were associated with lowrates of disease-free survival. Since the value ofMAX was found to be independent from otherprognostic factors by multivariate analysis, these results indicatethat MAX has a close correlation with metastasisor recurrence of breast cancer, making IV-DSA apromising prognostic factor.