Chemotherapy of disseminated breast cancer. Current status and prospects.

Chemotherapy once relegated to end stage patients has markedly improved with the use of combinations. Response rates with single agents have improved from 15 to 35%, to 50 to 70%, using combinations with an increase in complete response rates to about 25%. A series of four studies completed by the Eastern Cooperative Oncology Group over the past eight years typifies the improvement in response rates achieved by combinations as compared to single agents. Survival gain can be demonstrated for responders vs non-responders; however with current combinations, there is an apparent plateau in response rates (55 to 60%), durations of response (eight months) and survival for responders (18-22 months) as compared to survival of non-responders (six to eight months). Further improvement in response rates may occur by searching for new agents, combining hormonal and immunostimulation with chemotherapy or by sequencing non-crossresistant combinations. However, since most patients with breast cancer present with local or regional disease but go on to die of disseminated cancer, major improvements in survival are most likely to occur by treating this neoplasm as a systemic disease through cobmining effective local therapy with systemic treatments.