The impact of previous abdominal surgery on colorectal cancer patients undergoing laparoscopic surgery.

The current study aimed to investigate whether previous abdominal surgery (PAS) could affect the outcomes of colorectal cancer (CRC) surgery. We conducted the search strategy in three databases (PubMed, Embase, and the Cochrane Library) from inception to May 26, 2022. The short-term and long-term outcomes were compared between the PAS group and the non-PAS group. Odds ratios (ORs) and 95% confidence intervals (CIs) were pooled up. Stata (V.16.0) software was used for data analysis. We included 34,827 patients from 14 studies in the current study. After pooling up all the data, we found that there were higher proportions of overall complications (OR = 1.12, I2 = 4.65%, 95% CI 1.03 to 1.23, P = 0.01), ileus (OR = 1.96, I2 = 59.74%, 95% CI 1.12 to 3.44, P = 0.02) and mortality (OR = 1.26, I2 = 0.00%, 95% CI 1.11 to 1.42, P = 0.00) in the PAS group than the non-PAS group. Patients with a history of PAS had higher risks of overall complications and death following CRC surgery. However, it did not appear to significantly affect the short-term outcomes apart from ileus. Surgeons should raise awareness of patients with a history of PAS, and take steps to reduce postoperative complications and mortality.

Artificial intelligence-assisted endoscopic ultrasound in the diagnosis of gastrointestinal stromal tumors: a meta-analysis.

BACKGROUND AND AIMS: Endoscopic ultrasonography (EUS) is useful for the diagnosis of gastrointestinal stromal tumors (GISTs), but is limited by subjective interpretation. Studies on artificial intelligence (AI)-assisted diagnosis are under development. Here, we used a meta-analysis to evaluate the diagnostic performance of AI in the diagnosis of GISTs using EUS images. METHODS: PubMed, Ovid Medline, Embase, Web of science, and the Cochrane Library databases were searched for studies based on the EUS using AI for the diagnosis of GISTs, and a meta-analysis was performed to examine the accuracy. RESULTS: Overall, 7 studies were included in our meta-analysis. A total of 2431 patients containing more than 36,186 images were used as the overall dataset, of which 480 patients were used for the final testing. The pooled sensitivity, specificity, positive, and negative likelihood ratio (LR) of AI-assisted EUS for differentiating GISTs from other submucosal tumors (SMTs) were 0.92 (95% confidence interval [CI] 0.89-0.95), 0.82 (95% CI 0.75-0.87), 4.55 (95% CI 2.64-7.84), and 0.12 (95% CI 0.07-0.20), respectively. The summary diagnostic odds ratio (DOR) and the area under the curve were 64.70 (95% CI 23.83-175.69) and 0.950 (Q* = 0.891). CONCLUSIONS: AI-assisted EUS showed high accuracy for the automatic endoscopic diagnosis of GISTs, which could be used as a valuable complementary method for the differentiation of SMTs in the future.

Role of postoperative adjuvant radiotherapy for locally advanced laryngeal cancer: a meta-analysis.

BACKGROUND: Studies have shown mixed results on the role of postoperative adjuvant radiotherapy (PORT) in surgically managed locally advanced laryngeal cancer. OBJECTIVES: The aim of this study is to review and investigate the role of PORT in patients with locally advanced laryngeal cancer using meta-analysis. MATERIALS AND METHODS: Relevant studies were searched using PubMed and eligible information has been extracted. Then, meta-analysis of hazard ratio (HR) was performed to evaluate the role of PORT in locally advanced laryngeal cancer. RESULTS: This meta-analysis included 7 published studies containing 2007 patients. For overall survival (OS), patients of locally advanced laryngeal cancer who were treated with PORT have a combined hazard ratio (HR) of 0.67 with 95%CI (0.56, 0.79), compared to those who were not treated with PORT, which was significantly associated with better survival. PORT was also associated with a better disease-free survival (DFS) and local control rate (LCR) in patients with locally advanced laryngeal cancer. The pooled HR and 95%CI for DFS and LCR were 0.72 (0.53, 0.99) and 0.29 (0.09, 0.99), respectively. CONCLUSIONS AND SIGNIFICANCE: This study suggested that PORT could improve the survival of patients with surgically managed locally advanced laryngeal cancer.

Preclinical Evaluation of Chimeric Antigen Receptor-Modified T Cells Specific to Epithelial Cell Adhesion Molecule for Treating Colorectal Cancer.

Chimeric antigen receptor-modified T cells (CAR-T cells) have emerged as a promising cancer immunotherapy for solid tumors. Epithelial cell adhesion molecule (EpCAM) is overexpressed in a variety of tumors and is recognized as a biomarker for circulating tumor cells and cancer stem cells, representing an attractive target for adoptive T-cell immunotherapy. This study generated third-generation CAR-T cells with redirected specificity to EpCAM (EpCAM CAR-T) by lentiviral vector. The study demonstrated that EpCAM CAR-T cells can elicit lytic cytotoxicity to target cells in an EpCAM-dependent manner and secrete cytotoxic cytokines, including interferon gamma and tumor necrosis factor alpha. Furthermore, adoptive transfer of EpCAM CAR-T cells significantly delayed tumor growth and formation in xenograft models. In addition, the safety evaluation showed that CAR-T cells have no systemic toxicity in mice. The data confirmed the antitumor ability and safety of CAR-T cells targeting EpCAM and may provide a new target for CAR-T cell therapies in treating solid tumors.

Endoscopic ultrasound elastography in the diagnosis of pancreatic masses: A meta-analysis.

BACKGROUND AND AIMS: Endoscopic ultrasound (EUS) elastography is a novel non-invasive technique that can be used for distinguishing benign from malignant pancreatic masses. However, the studies have reported widely varied sensitivities and specificities. A meta-analysis was performed to assess the performance of EUS elastography for the differentiation of benign and malignant pancreatic masses. METHODS: All the eligible studies were searched by PubMed, Medline, Embase, and the Cochrane Library. Sensitivity, specificity, positive likelihood ratio (LR), negative LR, and area under the curve (AUC) were calculated to examine the accuracy. RESULTS: A total of nineteen studies which included 1687 patients were analyzed. The pooled sensitivity and specificity for the diagnosis of malignant pancreatic masses were 0.98 (95% confidence interval [CI] 0.96-0.99) and 0.63 (95% CI 0.58-0.69) for qualitative EUS elastography, 0.95 (95% CI 0.93-0.97) and 0.61 (95% CI 0.56-0.66) for quantitative EUS elastography, respectively. The positive and negative LR were 2.60 (95% CI 1.84-3.66) and 0.05 (95% CI 0.02-0.10) for qualitative EUS elastography, 2.64 (95% CI 1.82-3.82) and 0.10 (95% CI 0.06-0.16) for quantitative EUS elastography, respectively. The summary diagnostic odds ratio (DOR) and the AUC were 60.59 (95% CI 28.12-130.56) and 0.91 (Q* = 0.842) for qualitative EUS elastography, 30.09 (95% CI 15.40-58.76) and 0.93 (Q* = 0.860) for quantitative EUS elastography. CONCLUSIONS: Our meta-analysis shows that both qualitative and quantitative EUS elastography have high accuracy in the detection of malignant pancreatic masses, which could be used as a valuable complementary method to EUS-FNA for the differentiation of pancreatic masses in the future.

5-Azacytidine promotes invadopodia formation and tumor metastasis through the upregulation of PI3K in ovarian cancer cells.

The high incidence of metastasis accounts for most of the lethality of ovarian cancer. Invadopodia are small, specialized types of machinery that degrade the extracellular matrix and are thus involved in the invasion and metastasis of cancer cells. The formation of invadopodia is regulated by both genetic and epigenetic factors. However, the ways by which methylation/demethylation regulates the dynamics of invadopodia in ovarian cancer are largely unknown. In this study, we found that the inhibition of methylation by 5-AZ (5-Azacytidine) increased the formation of invadopodia and enhanced degradation of the extracellular matrix in ovarian cancer cells. In mouse xenograft models, treatment with 5-AZ increased the number of metastatic nodules, which suggests an elevated potential for metastasis by demethylation. Further investigation indicated that the inhibition of methylation elevated the transcription of PIK3CA and upregulated genes involved in the PI3K-AKT signaling pathway. In addition, this induction likely occurs though the epigenetic regulation of PIK3CA because analyses of the DNA methylation level of the PIK3CA promoter region found that 5-AZ treatment decreased the methylation of CpG islands in SKOV3 and A2780 cells. Our study demonstrated that epigenetic factors regulate the metastatic potential of ovarian cancer cells and provide rationale for therapies that inhibit PI3K- invadopodia-mediated metastasis.

Bevacizumab Addition in Neoadjuvant Treatment Increases the Pathological Complete Response Rates in Patients with HER-2 Negative Breast Cancer Especially Triple Negative Breast Cancer: A Meta-Analysis.

BACKGROUND: Neoadjuvant therapy is administered to breast cancer patients as an induction process before surgery or radiotherapy to reduce tumor size. Human epidermal growth factor receptor-2 (HER-2) negative breast cancer lacks effective standard target therapy. Bevacizumab has a controversial role in the treatment of breast cancer and we conduct a meta-analysis to evaluate the value of adding bevacizumab in neoadjuvant regimen. METHODS: Potentially eligible studies were retrieved using PubMed, EMBASE and Medline. Clinical characteristics of patients and statistical data with pathological complete response (pCR) data were collected. Then a meta-analysis model was established to investigate the correlation between administration of bevacizumab in neoadjuvant therapy and pCR rates in HER-2 negative breast cancer. RESULTS: Seven eligible studies and 5408 patients were yielded. The pCR rates for "breast" or "breast plus lymph node" were similar. In subgroup analysis, we emphasized on patients with triple-negative breast cancer (TNBC). In the criterion of "lesions in breast" the pooled ORs was 1.55 [1.29, 1.86], P<0.00001 and regarding to the evaluation criterion of "lesions in breast and lymph nodes", the pooled ORs was 1.48 [1.23, 1.78], P<0.0001, in favor of bevacizumab administration. CONCLUSION: According to our pooled results, we finally find that bevacizumab addition as a neoadjuvant chemotherapy component, for induction use with limited cycle to improve the pCR rates and patients may avoid long-term adverse event and long-term invalid survival improvement. Especially in subgroup analysis, pCR rates could be improved significantly and physicians could consider bevacizumab with caution. As patients could avoid the adverse event caused by long-term using of bevacizumab, long-term quality of life improvement may be achieved, especially in TNBC.

Establishing guidelines for CAR-T cells: challenges and considerations.

T cells, genetically modified by chimeric antigen receptors (CAR-T), are endowed with specificity to a desired antigen and are cytotoxic to cells expressing the targeted antigen. CAR-T-based cancer immunotherapy is a promising therapy for curing hematological malignancy, such as acute lymphoid leukemia, and is promising for extending their efficacy to defeat solid tumors. To date, dozens of different CAR-T cells have been evaluated in clinical trials to treat tumors; this necessitates the establishment of guidelines for the production and application of CAR-T cells. However, it is challenging to standardize CAR-T cancer therapy because it involves a combination of gene therapy and cell therapy. In this review, we compare the existing guidelines for CAR-T cells and discuss the challenges and considerations for establishing guidance for CAR-T-based cancer immunotherapy.

Hurdles of CAR-T cell-based cancer immunotherapy directed against solid tumors.

Recent reports on the impressive efficacy of chimeric antigen receptor (CAR)-modified T cells against hematologic malignancies have inspired oncologists to extend these efforts for the treatment of solid tumors. Clinical trials of CAR-T-based cancer immunotherapy for solid tumors showed that the efficacies are not as remarkable as in the case of hematologic malignancies. There are several challenges that researchers must face when treating solid cancers with CAR-T cells, these include choosing an ideal target, promoting efficient trafficking and infiltration, overcoming the immunosuppressive microenvironment, and avoiding associated toxicity. In this review, we discuss the obstacles imposed by solid tumors on CAR-T cell-based immunotherapy and strategies adopted to improve the therapeutic potential of this approach. Continued investigations are necessary to improve therapeutic outcomes and decrease the adverse effects of CAR-T cell therapy in patients with solid malignancies in the future.

Targeting of cancer­associated fibroblasts enhances the efficacy of cancer chemotherapy by regulating the tumor microenvironment.

Cancer­associated fibroblasts (CAFs), key components of the tumor stroma, can regulate tumorigenesis by altering the tumor microenvironment in variety of ways to promote angiogenesis, recruit inflammatory immune cells and remodel the extracellular matrix. Using a murine xenograft model of colon carcinoma, the present study observed that oxaliplatin increased the accumulation of CAFs and stimulated the production of cytokines associated with CAFs. When oxaliplatin was combined with the small­molecule dipeptidyl peptidase inhibitor PT­100, which inhibits CAFs by targeting fibroblast activation protein (FAP), the accumulation of CAFs was markedly reduced, xenograft tumor growth was significantly suppressed and the survival of the mice increased, compared to those of mice treated with oxaliplatin or PT­100 alone. Furthermore, the xenograft tumor tissues of mice treated with oxaliplatin and PT­100 contained lower numbers of tumor­associated macrophages and dendritic cells, expressed lower levels of cytokines associated with CAFs and had a lower density of CD31+ endothelial cells. The present study demonstrated that pharmacological inhibition of CAFs improved the response to chemotherapy, reduced the recruitment of immune tumor­promoting cells and inhibited angiogenesis. Combining chemotherapy with agents which target CAFs may represent a novel strategy for improving the efficacy of chemotherapy and reducing chemoresistance.

Contrast-enhanced sonography for the identification of benign and malignant thyroid nodules: Systematic review and meta-analysis.

PURPOSE: The use of contrast-enhanced sonography (CEUS) has yielded promising results in the differentiation of thyroid nodules. We conducted this meta-analysis to assess its performance in identifying and distinguishing between benign and malignant thyroid nodules. METHODS: PubMed, Medline, Embase, and the Cochrane Library were searched for studies published through the end of December 2013. Sensitivity, specificity, positive and negative likelihood ratios, diagnostic odds ratio, and area under the curve were calculated. RESULTS: A total of 13 studies were included in this meta-analysis. For the diagnosis of malignant thyroid nodules worldwide, the overall mean rates of sensitivity and specificity of CEUS were 90% (95% confidence interval [CI], 88-93%) and 86% (95% CI, 83-89%), respectively. The summary diagnostic odds ratio was 52.83 (95% CI, 21.71-128.55), and the area under the curve for the summary receiver operating characteristic curve was 0.94 (95% CI, 0.90-0.98). CONCLUSIONS: This meta-analysis indicates that CEUS may be a valuable supplemental method, with high rates of sensitivity and specificity, to use for identifying and distinguishing between benign and malignant thyroid nodules.

Radiotherapy combined with chemotherapy versus radiotherapy alone for early stage nasal natural killer/T-cell lymphoma: a meta-analysis.

OBJECTIVE: To compare the efficacy of radiotherapy (RT) plus chemotherapy (CMT) versus RT alone for early stage nasal natural killer (NK)/T-cell lymphoma. METHODS: All the eligible studies were searched by PubMed, Medline, Embase and the Cochrane Library. The meta-analysis was performed to compare odds ratios (ORs) for overall survival (OS), disease-free survival (DFS) and progression-free survival (PFS). RESULTS: Eight studies were included in the meta-analysis. Chemotherapy group did not significantly differ from RT group. The pooled OR and 95% confidence interval (CI) for 1-year, 3-year, 5-year and 10-year OS was 1.25 [0.84, 1.87], 1.10 [0.76, 1.58], 0.83 [0.59, 1.17] and 1.05 [0.70, 1.56]. In addition, the combined OR and 95% CI for 5-year DFS and PFS were 0.96 [0.53, 1.73] and 0.71 [0.45, 1.12]. CONCLUSIONS: The current evidence suggests that CMT was not superior to RT alone. Radiotherapy may be still the main method in the treatment of early stage nasal NK/T-cell lymphoma.

Intensity-modulated radiation therapy versus 2D-RT or 3D-CRT for the treatment of nasopharyngeal carcinoma: A systematic review and meta-analysis.

OBJECTIVE: To compare clinical treatment outcomes and late toxicities of intensity-modulated radiation therapy (IMRT) with those obtained with two-dimensional radiation therapy (2D-RT) or three-dimensional conformal radiation therapy (3D-CRT) in nasopharyngeal carcinoma (NPC). MATERIALS AND METHODS: We searched all the eligible studies from the Cochrane Library, PubMed, Medline, and Embase. The meta-analysis was performed to compare odds ratio (OR) for overall survival (OS), tumor local control (LC), and late toxicities. RESULTS: A total of eight studies met the criteria to perform a meta-analysis including 3570 participants, with 1541 patients in the IMRT group and 2029 in the 2D-RT or 3D-CRT group. The IMRT group was associated with a better 5-year overall survival (OR=1.51; 95% confidence interval (CI) 1.23-1.87; p=0.0001), and tumor local control (LC) (OR=1.94; 95% CI 1.53-2.46; p<0.00001). According to CTCAE v3.0 (Common Terminology Criteria for Adverse Events) and RTOG/EORTC (Radiation Therapy Oncology Group/European Organisation for Research and Treatment of Cancer), the incidence of late xerostomia in those who received IMRT was significantly lower than that of the control group (OR=0.18; 95% CI, 0.07-0.46; p=0.0004). In addition, the radiation-induced chronic toxicities rate of trismus and temporal lobe neuropathy (TLN) were also significantly lower in the IMRT group than in the control group (OR=0.18; 95% CI 0.04-0.83; p=0.03; OR=0.44; 95% CI 0.28-0.69; p=0.0003, respectively). CONCLUSIONS: This systematic review and meta-analysis demonstrated that IMRT mayobtain a better antitumor effect, and significantly decrease the incidence of radiation-induced late toxicities in patients with NPC.

Down-regulation of MFG-E8 by RNA interference combined with doxorubicin triggers melanoma destruction.

The pathogenic mechanism of malignant melanoma involves the dynamic interplay of transformed cell and normal host cell, but cancer treatments always target each partition separately. In the tumor microenvironment, milk fat globule epidermal growth factor-8 (MFG-E8) is a secreted glycoprotein highly expressed in the vertical growth phase of melanoma, leading to tumor progression through coordinated αvß3 and αvß5 integrin signaling in tumor cells and host cells. Doxorubicin (Dox) is one of the most widely used antitumor drugs against a lot of solid tumors, including melanoma. In this work, Dox was used to combine with down-regulation of MFG-E8 by RNA interference (RNAi) in order to determine the synergistic effect of the antitumor activity in vivo. And the possible mechanisms were investigated. Results showed that combination group (MFG-E8 RNAi plus Dox) could inhibit the growth of melanoma more effectively than monotherapy or control groups. We found that the combination treatment induced more tumor cell apoptosis and inhibited more neovascularization than other groups. Moreover, this combination treatment attenuated CD4(+) CD25(+) Foxp3(+) Treg cells in tumor-infiltrating lymphocytes compared with other groups. Our findings suggested that MFG-E8 down-regulation enhanced the antitumor function of chemotherapy through coordinated cell apoptosis and immune-mediated mechanisms, which might be a feasible way for cancer therapy.

3D conformal radiotherapy combined with transcatheter arterial chemoembolization for hepatocellular carcinoma.

AIM: To compare transcatheter arterial chemoembolization (TACE) and 3D conformal radiotherapy (3D-CRT) with TACE monotherapy in hepatocellular carcinoma (HCC). METHODS: We searched all the eligible studies from the Cochrane Library, PubMed, Medline, Embase, and CNKI. The meta-analysis was performed to assess the survival benefit, tumor response, and the decline in α-fetoprotein (AFP) level. According to the heterogeneity of the studies, pooled OR with 95%CI were calculated using the fixed-effects or random-effects model. An observed OR > 1 indicated that the addition of 3D-CRT to TACE offered survival benefits to patients that could be considered statistically significant. Statistical analyses were performed using Review Manager Software. RESULTS: Ten studies met the criteria to perform a meta-analysis including 908 HCC participants, with 400 patients in the TACE/3D-CRT combination group and 508 in the TACE alone group. TACE combined with 3D-CRT significantly improved 1-, 2- and 3-year overall survival compared with TACE monotherapy (OR = 1.87, 95%CI: 1.37-2.55, P < 0.0001), (OR = 2.38, 95%CI: 1.78-3.17, P < 0.00001) and (OR = 2.97, 95%CI: 2.10-4.21, P < 0.00001). In addition, TACE plus 3D-CRT was associated with a higher tumor response (complete remission and partial remission) (OR = 3.81; 95%CI: 2.70-5.37; P < 0.00001), and decline rates of AFP level (OR = 3.24, 95%CI: 2.09-5.02, P < 0.00001). CONCLUSION: This meta-analysis demonstrated that TACE combined with 3D-CRT was better than TACE monotherapy for patients with HCC, which needs to be confirmed by large multicenter trials．

Microvessel density as a prognostic factor in bladder cancer: a systematic review of literature and meta-analysis.

BACKGROUND: Many studies have shown that microvessel density (MVD) could play a potential value as prognostic biomarkers of tumors. The aim of this systematic review and meta-analysis is to evaluate the association between MVD and survival in patients with bladder cancer. METHODS: Relevant literature was identified using PubMed and EMBASE. The eligible studies were assessed for quality using REMAPK (REporting recommendations for tumor MARKer prognostic studies (REMARK)). The patients' clinical characteristics and survival outcomes in eligible studies were extracted. And then, data were synthesized to evaluate the prognostic role of the MVD in bladder cancer with hazard ratio (HR), while the heterogeneity among studies was examined using the I^{2}. RESULTS: This meta-analysis included 10 eligible studies conducted between 1998 and 2011 dealing with bladder cancer. The combined HRs and 95% confidence interval [95% CI] for disease-free survival (DFS) was 2.24 [1.20,4.17], for overall survival (OS) was 1.16 [1.02,1.33] and 1.68 [1.15,2.45] for disease-specific survival (DSS).There was evidence heterogeneity between studies, and the disease stage was a key factor for heterogeneity in subgroup analysis. CONCLUSIONS: Our studies suggested that high MVD was significantly associated with poor survival and MVD could serve as a prognostic biomarker in patients with bladder cancer.

Matched-pair comparisons of stereotactic body radiotherapy (SBRT) versus surgery for the treatment of early stage non-small cell lung cancer: a systematic review and meta-analysis.

PURPOSE: A population-based matched-pair comparison was performed to compare the efficacy of stereotactic body radiotherapy (SBRT) versus surgery for early-stage non-small cell lung cancer (NSCLC). METHODS: All the eligible studies were searched by PubMed, Medline, Embase, and the Cochrane Library. The meta-analysis was performed to compare odds ratios (OR) for overall survival (OS), cancer-specific survival (CSS), disease-free survival (DFS), local control (LC), and distant control (DC). RESULTS: Six studies containing 864 matched patients were included in the meta-analysis. The surgery was associated with a better long-term OS in patients with early-stage NSCLC. The pooled OR and 95% confidence interval (CI) for 1-year, 3-year OS were 1.31 [0.90, 1.91] and 1.82 [1.38, 2.40], respectively. However, the difference in 1-year and 3-year CSS, DFS, LC and DC was not significant. CONCLUSIONS: This systematic review found a superior 3-year OS after surgery compared with SBRT, which supports the need to compare both treatments in large prospective, randomized, controlled clinical trials.

Irradiated tumor cells of lipopolysaccharide stimulation elicit an enhanced anti-tumor immunity.

PURPOSE: Lipopolysaccharide (LPS) is a major component of the outer surface membrane of Gram-negative bacteria which has been proved an effective immune enhancer. Here, we investigated the anti-tumor effect of irradiated tumor cells that stimulated by LPS in mouse xenografts models. METHODS: Tumor cells were irradiated after stimulation with 1 µg/mL LPS for 48 h. The C57BL/6 mice were immunized subcutaneously with irradiated tumor cells. The anti-tumor effect of lymphocytes of immunized mice was investigated. The cytotoxicity of spleen lymphocytes from immunized mice was determined by a standard (51)Cr-release assay. The roles of immune cell subsets in anti-tumor activity were assessed by injected intraperitoneally with monoclonal antibodies. RESULTS: We observed that the vaccine of irradiated tumor cell with LPS-stimulated elicited a stronger protective anti-tumor immunity than other controls. Adoptive transfer of lymphocytes of immunized mice showed that the cellular immune response was involved in the anti-tumor effect. And this effect was achieved by activation of antigen-specific CD8(+) T cell response and reduction of myeloid-derived suppressor cells (MDSCs, Gr1(+) CD11b (+) ), which were confirmed by depletion of immune cell subsets and flow cytometry analysis. CONCLUSIONS: In summary, our study showed that stimulation of LPS was able to enhance anti-tumor immunity of vaccination with tumor cells after irradiation treatment, which might be a new strategy for cancer therapy.

Diagnostic accuracy of 18F-FDG-PET in patients with testicular cancer: a meta-analysis.

OBJECTIVE: Fluorine-18-fluorodeoxyglucose positron emission tomography (18F-FDG-PET) is a new technique for identifying different malignant tumors using different uptake values between tumor cells and normal tissues. Here we assessed the diagnostic accuracy of 18F-FDG-PET in patients with testicular cancer by pooling data of existing trials in a meta-analysis. METHODS: PubMed/MEDLINE, Embase and Cochrane Central Trials databases were searched and studies published in English relating to the diagnostic value of FDG-PET for testicular cancer were collected. The summary receiver operating characteristic (SROC) curve was used to examine the FDG-PET accuracy. RESULTS: A total of 16 studies which included 957 examinations in 807 patients (median age, 31.1 years) were analyzed. A meta-analysis was performed to combine the sensitivity and specificity and their 95% confidence intervals (CIs), from diagnostic odds ratio (DOR), positive likelihood ratios (PLR), negative likelihood ratio (NLR). SROC were derived to demonstrate the diagnostic accuracy of FDG-PET for testicular cancer. The pooled sensitivity and specificity were 0.75 (95% confidence interval (CI), 0.70-0.80) and 0.87 (95% CI, 0.84-0.89), respectively. The pooled DOR was 35.6 (95% CI, 12.9-98.3). The area under the curve (AUC) was 0.88. The pooled PLR and pooled NLR were 7.80 (95% CI, 3.73-16.3) and 0.31 (95% CI, 0.23-0.43), respectively. CONCLUSION: In patients with testicular cancer, 18F-FDG-PET demonstrated a high SROC area, and could be a potentially useful tool if combined with other imaging methods such as MRI and CT. Nevertheless, the literature focusing on the use of 18F-FDG-PET in this setting still remains limited.