Background: Chemotherapy is a mainstay of tumor therapy, however, it is predominantly applied according to empirically developed recommendations derived from statistical relapse rates occurring years after the treatme...Background: Chemotherapy is a mainstay of tumor therapy, however, it is predominantly applied according to empirically developed recommendations derived from statistical relapse rates occurring years after the treatment in the adjuvant situation and from progression-free interval data in the metastatic situation, without any possibility of individually determining the efficacy in the adjuvant situation and with loss of time and quality of life in the metastatic situation if the drugs chosen are not effective. Here, we present a method to determine the efficiency of chemotherapeutic drugs using tumor cells circulating in blood as the part of the tumor actually available in the patient’s body for chemosensitivity testing. Methodology/Principal Findings: After only red blood cell lysis, omitting any enrichment (analogous to other blood cell enumeration methods, including rare CD34 cells), the white cells comprising the circulating epithelial tumor cells (CETC) are exposed to the drugs in question in different concentrations and for different periods of time. Staining with a fluorescence-labeled anti-epithelial antibody detects both vital and dying tumor cells, distinguishing vital from dying cells through membrane permeability and nuclear staining with propidium iodide. Increasing percentages of dying tumor cells are observed dependent on time and concentration. The sensitivity can vary during therapy and was correlated with decrease or increase in CETC and clinical outcome. Conclusions/Significance: Thus, we are able to show that chemosensitivity testing of circulating tumor cells provides real-time information about the sensitivity of the tumor present in the patient, even at different times during therapy, and correlates with treatment success.展开更多
Introduction: Monitoring the response of CETC to therapy in lung cancer allows early detection of patients at risk of progression. Analysis of the EGFR-gene amplification in these cells may help to characterize patien...Introduction: Monitoring the response of CETC to therapy in lung cancer allows early detection of patients at risk of progression. Analysis of the EGFR-gene amplification in these cells may help to characterize patients who might benefit from tyrosine kinase inhibitors. Methods: CETCs were quantified at least twice during treatment from blood of 52 patients with advanced non small cell lung cancer (NSCLC) using fluorescence labelled anti-EpCAM. EGFR-gene amplification was analysed in these cells with double probe (EGFR/CEP7) using FISH analysis. Results: Progression of the tumor was observed in 30 of the 52 patients (58%). With respect to changes in CETCs during therapy and progression free survival 31 patients showed a decrease in CETCs, 2 developing a single brain metastasis and 12 progressive disease;20 patients showed an increase in CETC more than twofold 16 of which developed progressive disease. The difference was highly significant (p=0.007 Fisher’s exact test) irrespective of age, sex, tumor size, pathological type and therapy. Kaplan-Meier progression free survival was significantly different between patients with decreasing and increaseing CETC (p=0.038). 5/20 patients tested were positive for EGFR amplification with 85-100% of EpCAM positive cells showing this chromosomal abnormality. One patient could be followed during therapy with increasing CETC during therapy with bevacizumab followed by relapse. He subsequently received erlotinib resulting in a decrease in CETC and is still free of progress after 516 days. Conclusions: These results show that peripherally circulating tumor cells in patients with advanced NSCLC are influenced by systemic chemotherapy and an increase in spite of therapy is a marker of aggressiveness of the tumor cells. Determination of the EGFR amplification might help to better treat part of these patients.展开更多
文摘Background: Chemotherapy is a mainstay of tumor therapy, however, it is predominantly applied according to empirically developed recommendations derived from statistical relapse rates occurring years after the treatment in the adjuvant situation and from progression-free interval data in the metastatic situation, without any possibility of individually determining the efficacy in the adjuvant situation and with loss of time and quality of life in the metastatic situation if the drugs chosen are not effective. Here, we present a method to determine the efficiency of chemotherapeutic drugs using tumor cells circulating in blood as the part of the tumor actually available in the patient’s body for chemosensitivity testing. Methodology/Principal Findings: After only red blood cell lysis, omitting any enrichment (analogous to other blood cell enumeration methods, including rare CD34 cells), the white cells comprising the circulating epithelial tumor cells (CETC) are exposed to the drugs in question in different concentrations and for different periods of time. Staining with a fluorescence-labeled anti-epithelial antibody detects both vital and dying tumor cells, distinguishing vital from dying cells through membrane permeability and nuclear staining with propidium iodide. Increasing percentages of dying tumor cells are observed dependent on time and concentration. The sensitivity can vary during therapy and was correlated with decrease or increase in CETC and clinical outcome. Conclusions/Significance: Thus, we are able to show that chemosensitivity testing of circulating tumor cells provides real-time information about the sensitivity of the tumor present in the patient, even at different times during therapy, and correlates with treatment success.
文摘Introduction: Monitoring the response of CETC to therapy in lung cancer allows early detection of patients at risk of progression. Analysis of the EGFR-gene amplification in these cells may help to characterize patients who might benefit from tyrosine kinase inhibitors. Methods: CETCs were quantified at least twice during treatment from blood of 52 patients with advanced non small cell lung cancer (NSCLC) using fluorescence labelled anti-EpCAM. EGFR-gene amplification was analysed in these cells with double probe (EGFR/CEP7) using FISH analysis. Results: Progression of the tumor was observed in 30 of the 52 patients (58%). With respect to changes in CETCs during therapy and progression free survival 31 patients showed a decrease in CETCs, 2 developing a single brain metastasis and 12 progressive disease;20 patients showed an increase in CETC more than twofold 16 of which developed progressive disease. The difference was highly significant (p=0.007 Fisher’s exact test) irrespective of age, sex, tumor size, pathological type and therapy. Kaplan-Meier progression free survival was significantly different between patients with decreasing and increaseing CETC (p=0.038). 5/20 patients tested were positive for EGFR amplification with 85-100% of EpCAM positive cells showing this chromosomal abnormality. One patient could be followed during therapy with increasing CETC during therapy with bevacizumab followed by relapse. He subsequently received erlotinib resulting in a decrease in CETC and is still free of progress after 516 days. Conclusions: These results show that peripherally circulating tumor cells in patients with advanced NSCLC are influenced by systemic chemotherapy and an increase in spite of therapy is a marker of aggressiveness of the tumor cells. Determination of the EGFR amplification might help to better treat part of these patients.
