According to a new study published in the Journal of Clinical Oncology, the identification of disseminated tumor cells (DTCs) in the bone marrow indicates high-risk patients insufficiently treated with adjuvant chemotherapy consisting of 5-fluorouracil, epirubicin, and cyclophosphamide.
Knowing that DTCs in the bone marrow predict survival during the early stages of breast cancer, researchers sought to investigate the role of DTC in identifying patients with breast cancer insufficiently treated with adjuvant chemotherapy and to determine if DTC monitoring during secondary treatment can predict survival.
Researchers identified 1,066 patients with early breast cancer who had received six cycles of 5-fluorouracil, epirubicin, and cyclophosphamide and a DTC result 8 to 9 months after chemotherapy. Of those, 7.2% had DTCs present in their bone marrow and 72 patients then went on to receive docetaxel. Patients with DTCs following docetaxel treatment had a significantly decreased disease-free interval compared with patients with no DTCs following treatment (HR, 7.58; 95% CI, 2.3 to 24.7).
Patients treated with docetaxel who had no DTCs after treatment had a similar disease-free interval compared with patients with no DTCs at 1 to 2 or 8 to 9 months after initial adjuvant chemotherapy. The findings suggest that the presence of DTC identifies patients at high-risk for relapse following adjuvant chemotherapy and DTC monitoring following secondary treatment was associated with improved survival.
This study explores the use of DTCs for identification of patients insufficiently treated with adjuvant therapy so they can be offered secondary adjuvant treatment and the subsequent surrogate marker potential of DTCs for outcome determination.
DTC status identifies high–risk patients after FEC chemotherapy, and DTC monitoring status after secondary treatment with docetaxel correlated strongly with survival. This emphasizes the potential for DTC analysis as a surrogate marker for adjuvant treatment effect in breast cancer.