Background: Detecting circulating tumor cells (CTCs) has become a new strategy for predicting the prognosis of cancer patients. However, limited systematic research evidence is available for the detection of CTCs in various gastrointestinal tumors such as esophageal cancer (EC), colorectal cancer (CRC) and gastric cancer (GC). This topic was addressed to assess the prognostic significance of CTCs in gastrointestinal tumors. Methods: We conducted a literature search according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist (from November 20, 2021). We performed a meta-analysis using the random effects model and Review Manager 5.3 software (The Cochrane Collaboration, Copenhagen, Denmark) according to the inclusion and exclusion criteria, data extraction and evaluation methods. Results: Twenty-four articles met the inclusion criteria for this study, and they included 3803 EC, CRC and GC patients, including 1189 CTC-positive and 2462 CTC-negative cases. The meta-analysis showed that the presence of CTCs was associated with worse OS (HR = 2.05, 95% CI = 1.75–2.40, P = .060) and PFS (HR = 2.27, 95% CI = 1.79–2.89, P < .001). Further meta-regression and subgroup analyses showed that CTC-positive patients also showed worse OS and PFS in different subgroups. Conclusion: Our meta-analysis suggests that detecting CTCs in peripheral blood may be an important tool for improving the prognosis of patients with gastrointestinal tumors. Moreover, CTCs detection results could be used to develop personalized treatment plans in the future.

Background: This study aimed to compare the clinical efficacy and safety of microwave ablation (MWA) and radiofrequency ablation (RFA) for the treatment of spinal metastases. Methods: A literature search was performed using the PubMed, Web of Science, and Cochrane Library databases according to the PRISMA statement (as of September 20, 2022). Two independent investigators screened articles based on the inclusion and exclusion criteria and included studies with primary outcomes of pain relief, tumor control, and complications. Article quality was assessed using the Risk Of Bias In Non-randomized Studies of Interventions tool. Results: Sixteen articles were finally included in this study, including 630 patients with spinal metastases, with ages ranging from 51.4 to 71.3 years. Of these, 393 (62.4%) underwent MWA and 237 (37.6%) underwent RFA. After MWA and RFA treatment, visual analog scale scores significantly decreased, and the local tumor control rates were all above 80%. Complications were reported in 27.4% of patients treated with MWA compared with 10.9% of patients treated with RFA. Conclusion: The results of this systematic review suggest that MWA alone or in combination with surgery and RFA in combination with other modalities may improve pain caused by primary tumor metastasis to the spine, and MWA alone or in combination with surgery may have better local tumor control. However, MWA appears to result in more major complications than RFA in combination with other treatment modalities.