Clinical course of breast cancer patients with osseous metastasis treated with combination chemotherapy

Between July 1973 and December 1979, 1171 patients with meta static breast cancer were treated with doxorubicin‐containing chemotherapy. Of those patients, 195 had osseous metastases only. Upon initial diagnosis, 48% had osteolytic metastases; 13% had osteoblastic metastases; 38% had mixed metastases; and 1% had diffuse osteoporosis without any obvious bone destruction. The most common sites of involvement were the dorsal spine (62%), lumbosacral spine (72%), and pelvis (79%). Objective response to chemotherapy was observed in 59% of patients; complete responses were noted in 7%, and partial responses in 52%. The median survival was 28 months (range, 1–118 months). The median time lapse between the start of chemotherapy and disease progression was 14 months (range, 1–109 months). In 32 patients who responded to the treatment, chemotherapy was discontinued after 2 years, and their median duration of continued remission without evidence of progressive disease was 14 months. Two of the 32 patients were still in remission at 39 and 75 months after the completion of therapy. The incidence of pathological fractures was 57%; the most common sites were the spine, which sustained compression fractures, and the ribs. The incidences of hypercalcemia and spinal cord compression due to metastases were 19% and 10%, respectively.