Breast cancer therapy response detected early

A decrease in circulating tumor cells (CTCs) shows that chemotherapy is working in patients with metastatic breast cancer, according to the results of a Georgetown University study reported at the 2007 San Antonio Breast Cancer Symposium. Periodic measurement of CTCs can indicate how well chemotherapy is working, allowing doctors to switch patients to a more effective course of treatment if there is poor treatment response. The study results for the first 54 of a planned group of 100 patients were presented at the Symposium. CTC measurements were taken before treatment began and again 3 to 4 weeks later following the first completed cycle of chemotherapy. Blood samples continued to be collected every 3 to 4 weeks throughout the patients’ treatment. Researchers said that after following the women for as long as 2 years while comparing CTC levels with the findings of X-rays, CT scans and other conventional tests, they found that women with higher CTC levels (compared with women with less than 5 CTCs per 7.5 ml) has a 5-fold increased risk of disease progression. “We don’t necessarily need new drugs,” said principal investigator Dr. Minetta C. Liu. “We just need to use the old ones in a smarter way. By measuring CTCs, we can see right away if the drug is working or not and limit toxicity.”