The authors assess prevalence of anemia in a population of patients anticipating radiation therapy. They also characterize the anemia and determine its relationship to stage, inflammation, and mortality. Blood counts were recorded for 81 of 103 patients surveyed during August 1988. When available, iron studies were used to characterize anemia. Stage, treatment, and 3-year mortality were obtained from tumor registry data. Many patients had anemia of chronic disorders. Therefore, 16 adults with solid tumors anticipating radiation therapy were evaluated with complete blood counts, iron studies, chemistries, erythropoietin, and measures of inflammation. Of 81 patients, more than half were anemic. Thirteen of 17 patients with anemia and with iron studies had anemia of chronic disorders. Two-thirds of patients with anemia had advanced cancer, versus one third of patients without anemia. Twice as many patients with anemia compared with those without anemia died within 3 years. Of 16 patients studied intensively, 4 had anemia, advanced cancer, and died within 6 months, whereas all 12 patients without anemia lived longer. The 4 patients with anemia had an elevated iron index (7.95), erythrocyte sedimentation rate (86 mm per hour), and C-reactive protein (4.48 mg/dL) versus those of 12 patients without anemia and 10 volunteers. Erythropoietin levels were not different significantly among groups. Anemia indicated a poor prognosis during and before radiotherapy, and anemia of chronic disorders was associated with advanced cancer and a short survival rate.