New Approach for Interpreting Changes in Circulating Tumour Cells (CTC) for Evaluation of Treatment Effect in Metastatic Breast Cancer

Abstract

Aim: Attempts have been made to use CTC values for interpretation of treatment response and to guide change of chemotherapy by using a static cut-off of 5 CTC to stratify patients in favourable or unfavourable responders. We propose a new approach to interpret treatment effect using significant changes in CTC values (SCV-limits1) as grouping parameter for responders and non-responders to chemotherapy among metastatic breast cancer (mBC) patients. Method: CTC were analysed using the CellSearch System in blood from 47 mBC patients before the start of new chemotherapy and before the third cycle of therapy. The new and old approach to interpret changes in CTC values were compared in relation to progression free survival (PFS). Results: The new approach using significant CTC change (P = .032) and the old approach using static cut-off (P > .001) correlated significantly with PFS using a cohort of 47 patients. Conclusion: We propose a new approach to interpret significant changes between baseline and follow-up CTC values as a tool for assessing treatment effect in mBC. Our approach stratified patients in new risk groups that were stratified significantly with respect to PFS. More patients are needed to balance the size of the risk groups for better comparison to the existing approach based on a 5 CTC cut-off.

Circulating tumor cell status monitors the treatment responses in breast cancer patients: a meta-analysis

“…Finally, 50 studies were eligible for meta-analysis (Fig. 1)4591112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657.…”

Cut-Off Analysis of CTC Change under Systemic Therapy for Defining Early Therapy Response in Metastatic Breast Cancer

“…The data also pointed to a better prognosis for patients in whom CTC-status became negative after therapy, but this was less convincing, especially for PFS. Horn et al demonstrated the prognostic relevance of a significant change value of the CTC count between baseline and three therapy cycles to define a CTC evaluation method for the low and medium risk groups [35]. This method allows to also take initially CTC negative patients into account for CTC decrease.…”

Highly Selective Capture Surfaces on Medical Wires for Fishing Tumor Cells in Whole Blood

“…1,3 Enrichment, detection and counting of CTCs is very important because it allows for statistical predictions concerning the overall survival time and the response of patients to anticancer therapies. 6 While enrichment and counting is already a big step forward, molecular information and how the cells will respond to therapeutic efforts is still locked away inside them. Consequently, to obtain this information, a prerequisite for any personalized cancer drugs that target selected pathways, analytical downstream processes after cell isolation are needed.…”

“…Thus, information on the extent of the circulation of these cells is of great interest, especially at early stages in tumor development. CTC invasion into the blood can occur during any stage of tumor development, but it might even be provoked by diagnostic or therapeutic procedures (e.g., palpation, biopsy, surgery, drugs). , Enrichment, detection and counting of CTCs is very important because it allows for statistical predictions concerning the overall survival time and the response of patients to anticancer therapies . While enrichment and counting is already a big step forward, molecular information and how the cells will respond to therapeutic efforts is still locked away inside them.…”