The Efficacy Of Diagnosing Metastatic Cancer Using Cellsearch System: A Meta-Analysis

Background: As a new technology, CellSearch system count the circulating tumor cells in peripheral circulation. Several studies have investigated the value of this system. We conducted the meta-analysis to evaluate the efficacy of diganosing metastatic cancer using CellSearch system.Methods: A comprehensive search was performed in PUBMED, EMBASE and Cochrane Library et al, to retrieve relevant studies on detecting circulating tumor cells in peripheral blood of patients with metastatic carcinoma using CellSearch System. Articles selection and data extraction were carried out by two reviewers independently. Data on accuracy of included studies were extracted for further heterogeneity exploring, statistical pooling and SROC (summary receiver operating characteristics) analyzing using the MetaDiSc1.4 software. Source of heterogeneity was explored via regression analysis and sensitivity analysis, subsequently, it was solved by subset analysis.Results: Seven studies met our inclusion criteria, with 1983 persons involved. The heterogeneity (except for threshold effect) was found in these studies. The pooled accuracy indicators like sensitivity, specificity, and diagnostic odds ratio (DOR) were 0.42 (95% CI: 0.40-0.45), 0.96 (95% CI: 0.94-0.98), and 29.27 (95% CI: 10.69-80.12), respectively. The positive likelihood ratio (PLR) and negative likelihood ratio (NLR) were 15.10 (95%CI 3.92-58.20) and 0.47 (95%CI 0.37-0.59).The area under of SROC curve was 0.74 and the Q index was 0.69. The result of regression analysis expressed that various types of cancer cause heterogeneity mainly, and the heterogeneity can be improved after subset analysis.Conclusions: The efficacy of diagnosing metastatic cancer using CellSearch System is middling. This technology would be used as assisted diagnosis index of metastatic cancer, and also be used as a tool of monitoring metastatic cancer for continued researches in therapy and prognosis. As a new technology, CellSearch System needs more tests, which is designed rigorously and target independent cancer. Especially, the high detection ratio indicate the research value in the field of prostate cancer.