Prognostic role of pretreatment thrombocytosis on survival in patients with cervical cancer: a systematic review and meta-analysis

Abstract

Background This meta-analysis summarized the prognostic role of an elevated platelet count before treatment on survival outcomes in patients with cervical cancer. Methods The PubMed, Embase, and Cochrane library electronic databases were systematically searched for studies reporting the effect estimates with 95% confidence intervals (CIs) of pretreatment thrombocytosis on survival from the database inceptions to December 2018. The pooled hazard ratios (HRs) with 95% CIs for overall survival (OS), progression-free survival (PFS), and recurrence-free survival (RFS) were calculated using random-effects models. Results Nineteen retrospective studies that recruited 6521 patients with cervical cancer were eligible for this study. The summary results indicated that an elevated platelet count was significantly associated with a poor OS (HR 1.50; 95% CI 1.19–1.88; P = 0.001), PFS (HR 1.33; 95% CI 1.07–1.64; P = 0.010), and RFS (HR 1.66; 95% CI 1.20–2.28; P = 0.002). Sensitivity analysis indicated that the pooled PFS was variable after sequential exclusion of individual studies. The predictive value of pretreatment thrombocytosis on OS differed according to the publication year ( P = 0.039), country ( P = 0.013), and sample size ( P = 0.029), and the role of pretreatment thrombocytosis on PFS could be affected by the study quality ( P = 0.046). Conclusion The findings of this study indicated that an elevated platelet count before treatment was associated with poor OS, PFS, and RFS. These results require further verification in large-scale prospective studies. Electronic supplementary material The online version of this article (10.1186/s12957-019-1676-7) contains supplementary material, which is available to authorized users.

Prognostic Significance of Clinicopathological Factors Influencing Overall Survival and Event-Free Survival of Patients with Cervical Cancer: A Systematic Review and Meta-Analysis

“…Furthermore, we studied additional prognostic factors, such as age, cell type, hemoglobin level, histological grade, leukocytosis, NLR, PLR, SCCA level, thrombocytosis, tumor grade, and tumor volume. The above-mentioned results could be explained as follows: (1) The incidence of CC varies among different age-based groups, and the FIGO stage of CC also significantly differs among various age-based groups [ 2 ]; (2) Compared with squamous cell carcinoma, patients with adenocarcinoma may tend to have other extracervical spread, associating with a poor prognosis of CC patients [ 171 ]; (3) The hemoglobin level is significantly correlated to the tumor size and infiltrative phenotypes of tumors [ 172 , 173 ]; Moreover, the hemoglobin level may act as a surrogate marker of tumor hypoxia, which is significantly associated with resistance to radiotherapy [ 174 ]; (4) Histological grade, tumor grade, and tumor volume are significantly correlated to tumor extension and invasion, which may influence the prognosis of CC patients; (5) Leukocytosis in CC patients is associated with a poor prognosis, which may be related to a poor response to radiation therapy [ 100 ]; (6) Increased NLR is markedly associated with a large tumor size, advanced clinical stage, and positive LNI, resulting in shorter OS and EFS [ 15 ]; (7) Elevated PLR can induce inflammatory cytokines and chemokines, promoting the progression of cancer cells [ 175 ]; (8) Increased SCCA concentration can reflect the degree of cell proliferation for patients with CC [ 176 ]; and (9) Cancer treatment can induce thrombocytosis, cytokines or growth factors, receptors, and downstream effectors, playing an important role in the prognosis of CC [ 177 ].…”

Platelet-Derived GARP Induces Peripheral Regulatory T Cells—Potential Impact on T Cell Suppression in Patients with Melanoma-Associated Thrombocytosis

“…There has been an emerging role of platelets in the immunomodulation of cancer patients. Recent studies have indicated that platelets are present in the tumor microenvironment, and cancer-associated thrombocytosis has been linked to the promotion of metastasis, invasiveness, and tumor development and thus to poor clinical outcome in different tumor entities [4,43]. Tumors constantly activate the coagulation pathways, resulting in the generation of thrombin and consequently chronic platelet activation.…”

Thrombocytosis as a Biomarker in Type II, Non-Endometrioid Endometrial Cancer

“…Thrombocytosis as a clinical predictor of worse outcomes has been demonstrated across the gynecologic cancer continuum. In patients with cervical cancer, elevated platelets levels have been associated with worse recurrence free and overall survival, more advanced stage, larger tumors, and greater likelihood of treatment failure [ 19 , 20 , 21 ]. Among patients with epithelial ovarian cancer, thrombocytosis may be present in up to 62.5% of patients [ 22 ].…”