DISEASE CHARACTERISTICS: Refractory stage IV breast cancer Received high dose chemotherapy (HDC) with autologous or syngeneic peripheral blood stem cell transplantation (PBSCT) OR Stage IV breast cancer Failed to achieve complete response to HDC with autologous or syngeneic PBSCT at initial restaging following HDC No enrollment on protocol FHCRC-976, unless evidence of no response or progressive disease at initial restaging following transplantation Hormone receptor status: Not specified