Toxic effects of grade 4 or higher were observed in four patients who received anastrozole alone (1.2%) and in five patients who received combination therapy (1.4%) (P = 1.00). The four observed grade 4 toxic effects among patients who received anastrozole alone were thrombosis or embolism, joint pain, thrombocytopenia, and dyspnea. Two patients receiving the combination
therapy had grade 4 toxic effects (thrombosis or embolism in one patient and neutropenia or lymphopenia in one patient). In addition, there were three deaths in the group that received combination
therapy: one patient, 80 years of age, died from diverticular perforation and heparin-induced thrombocytopenia with thromboembolism; one patient, 83 years of age, died from cerebrovascular
ischemia after septic shock associated with worsening disease; and one patient, 73 years of age, who had a Zubrod’s performance score of 2, died from a thromboembolism.