Between 1958 and 1985, 107 patients with nonmetastatic inflammatory breast cancer (IBC) received radiotherapy as all or part of initial treatment at the Mallinckrodt Institute of Radiology. For this review, the diagnosis of IBC was made on the basis of either clinical or histopathologic criteria. Fifteen factors of potential prognostic significance were evaluated, by both univariate and multivariate analysis. For relapse-free survival, univariate analysis suggested prognostic value for initial tumor size, discrete versus diffuse tumor mass, adjuvant chemotherapy, and mastectomy. In the multivariate analysis, the independent prognostic factors, in order of significance, were mastectomy, diffuse versus discrete tumor mass, and race (marginal). For survival, univariate analysis suggested prognostic value for initial tumor size, diffuse versus discrete tumor mass, nodal stage, year of treatment, adjuvant chemotherapy, and mastectomy. In the multivariate analysis, the prognostic factors in order of significance were mastectomy and chemotherapy (marginal). The diagnostic selection group showed no prognostic value, suggesting that either clinical or histopathologic criteria justify the diagnosis of IBC. Our results appear to support a role for surgery as part of the combined modality approach to this disease.