In a study presented at the 35th Congress of the European Society for Medical Oncology（肿瘤学） (ESMO), Dr Giovanni Bernardo from Fondazione Maugeri in Pavia, Italy, presented results that suggested it may be possible to identify subsets（子集合） of metastatic（转移性的，变形的） breast cancer patients who are likely to respond to subsequent lines of chemotherapy（化学疗法） . Dr Bernardo's group analysed data from 980 women treated with chemotherapy for metastatic breast cancer in their centre between 1992 and 2006.

They found that the median overall survival grew progressively smaller for each successive chemotherapy regimen（养生法，政体） the patients were given. The time to treatment failure also shortened as each new regimen was tried, from a median of 9.2 months for first-line therapy, to 7.8 and 6.4 months for the second and third-line drugs. Beyond the third line, there was no significant decrease in the medial time to treatment failure for each successive therapy.

The researchers found that only one factor they analysed affected a patient's overall survival time. That factor was the time to treatment failure for each line of chemotherapy. In other words, the more benefit one type of therapy offered, the more benefit the subsequent therapy was likely to offer.

"The implications of our analysis for clinical practice concern the possibility of deciding which patients should be offered a third- or successive chemotherapy line, considering that there are multiple treatment options available today for metastatic disease, and increasing numbers of patients ask for more options when a particular treatment fails," said Dr Bernardo.