Prognostic value of stem-like circulating tumor cells in patients with cancer: a systematic review and meta-analysis

Despite increasing interest in the study of circulating tumor cells (CTC) subsets, especially epithelial-mesenchymal transition (EMT) and stem cells subsets of CTC that play a key role in tumor recurrence and metastasis, there is no evidence from meta-analyses that shows the correlation between stem-like CTCs and prognosis in cancer patients. Thus, we performed a meta-analysis to assess its prognostic value. Sixteen articles were screened by searching the PubMed, Embase, Cochrane, China National Knowledge Internet (CNKI) and Wanfang databases. The hazard ratio (HR) and 95% confidence interval (95% CI) extracted from each article were summarized. Patients with positive stem-like CTCs in peripheral blood had significantly shorter overall survival (OS, HR: 2.58, 95% CI 1.76–3.79, P < 0.00001), progression-free survival (PFS, HR: 2.21, 95% CI 1.26–3.89, P = 0.006) and disease-free survival (DFS, HR: 2.53, 95% CI: 1.12–5.70, P = 0.03). This study provides the first meta-analysis evidence for the prognostic value of stem-like CTCs, demonstrating that these cells are associated with poor prognosis in cancer patients. Systematic review registration CRD42022322062