The use of platelets as a clinical tool in oncology: opportunities and challenges

Platelets are small circulating anucleated cells mainly involved in thrombosis and hemostasis processes. Moreover, platelets play an active role in tumorigenesis and cancer progression, stimulating angiogenesis and vascular remodelling, and protecting circulating cancer cells from shear forces and immune surveillance. Several reports indicate that platelet number in the blood circulation of cancer patients is associated with prognosis and response to treatment. However, the mechanisms of platelets "education" by cancer cells and the crosstalk between platelets and tumor are still unclear, and the role of "tumor educated platelets" (TEPs) is achieving growing interest in cancer research. TEPs are a biological source of cancer-derived biomarkers, especially RNAs that are protected by platelets membrane from circulating RNases, and could serve as a non-invasive tool for tumor detection, molecular profiling and evolution during therapy in clinical practice. Moreover, short platelet lifespan offers the possibility to get a snapshot assessment of cancer molecular profile, providing a real-time tool. We review and discuss the potential and the clinical utility, in terms of cancer diagnosis and monitoring, of platelet count together with other morphological parameters and of the more recent and innovative TEP profiling.

Prognostic role of preoperative circulating systemic inflammatory response markers in primary breast cancer: meta-analysis

BACKGROUND

Circulating markers of the systemic inflammatory response are prognostic in several cancers, but their role in operable breast cancer is unclear. A systematic review and meta-analysis of the literature was carried out.

METHODS

A search of electronic databases up to August 2020 identified studies that examined the prognostic value of preoperative circulating markers of the systemic inflammatory response in primary operable breast cancer. A meta-analysis was carried out for each marker with more than three studies, reporting a HR and 95 per cent confidence interval for disease-free survival (DFS), breast cancer-specific survival (BCSS) or overall survival (OS).

RESULTS

In total, 57 studies were reviewed and 42 were suitable for meta-analysis. Higher neutrophil-to-lymphocyte ratio (NLR) was associated with worse overall survival (OS) (pooled HR 1.75, 95 per cent c.i. 1.52 to 2.00; P < 0.001), disease-free survival (DFS) (HR 1.67, 1.50 to 1.87; P < 0.001), and breast cancer-specific survival (BCSS) (HR 1.89, 1.35 to 2.63; P < 0.001). This effect was also seen with an arithmetically-derived NLR (dNLR). Higher platelet-to-lymphocyte ratio (PLR) was associated with worse OS (HR 1.29, 1.10 to 1.50; P = 0.001) and DFS (HR 1.58, 1.33 to 1.88; P < 0.001). Higher lymphocyte-to-monocyte ratio (LMR) was associated with improved DFS (HR 0.65, 0.51 to 0.82; P < 0.001), and higher C-reactive protein (CRP) level was associated with worse BCSS (HR 1.22, 1.07 to 1.39; P = 0.002) and OS (HR 1.24, 1.14 to 1.35; P = 0.002).

CONCLUSION

Current evidence suggests a role for preoperative NLR, dNLR, LMR, PLR, and CRP as prognostic markers in primary operable breast cancer. Further work should define their role in clinical practice, particularly reproducible thresholds and molecular subtypes for which these may be of most value.

Prognostic significance of the combination of preoperative red cell distribution width and platelet distribution width in patients with gastric cancer

BACKGROUND

Platelet distribution width (PDW) and red cell distribution width (RDW) are readily obtainable data, and are reportedly useful as prognostic indicators in some cancers. However, their prognostic significance is unclear in gastric cancer (GC).

METHODS

We enrolled 445 patients with histopathological diagnoses of gastric adenocarcinoma who had undergone curative surgeries.

RESULTS

According to the optimal cut-off value of PDW and RDW by receiver operating characteristic (ROC) analysis, we divided patients into PDW^High (≥ 16.75%), PDW^Low (< 16.75%), RDW^High (≥ 14.25%), and RDW^Low (< 14.25%) subgroups. Overall survival (OS) was significantly worse in patients with PDW^High than in those with PDW^Low (P = 0.0015), as was disease specific survival (P = 0.043). OS was also significantly worse in patients with RDW^High than in those with RDW^Low (P <  0.0001), as was disease specific survival (P = 0.0002). Multivariate analysis for OS revealed that both PDW and RDW were independent prognostic indicators. Patients were then given PDW-RDW score by adding points for their different subgroups (1 point each for PDW^High and RDW^High; 0 points for PDW^Low and RDW^Low). OS significantly differed by PDW-RDW score (P <  0.0001), as did disease specific survival (P = 0.0005). In multivariate analysis for OS, PDW-RDW score was found to be an independent prognostic indicator.

CONCLUSIONS

The prognosis of GC patients can be precisely predictable by using both PDW and RDW.

Prognostic Value of Preoperative Mean Platelet Volume and a Predictive Nomogram in Oral Squamous Cell Carcinoma Patients Based on Real-World Data

Objective

We aimed to identify new prognostic factors of oral squamous cell carcinoma (OSCC) among platelet-related parameters, establish a survival prediction model to predict the survival status of OSCC patients, and analyze the therapeutic effect of neoadjuvant chemotherapy on OSCC patients on the basis of real-world data.

Materials and Methods

The real-world data of patients with OSCC confirmed by pathologic examination at Cancer Hospital from January 2011 to January 2015 and May 2017 to January 2020 were collected. We analyzed clinicopathologic factors using a Cox regression analysis, the Kaplan-Meier method, and propensity score matching (PSM).

Results

The multivariate Cox regression analysis of not only validated the traditional prognostic factors such as tumor site, neural invasion, poor differentiation, and tumor-node-metastasis (TNM) stage but also identified a new prognostic factor, preoperative mean platelet volume (MPV) for overall survival (OS, HR, 0.47; 95% CI: 0.25–0.89, P = 0.020). A nomogram was created to predict the probability of 3-year and 5-year OS. We found that neoadjuvant chemotherapy improved OS in patients with OSCC.

Conclusion

Preoperative MPV, being associated with female, neoadjuvant chemotherapy, and advanced stage (Stage III and IV), may be a new prognostic factor for OS of patients with OSCC. The nomograms provided useful prediction for OS in OSCC patients. Neoadjuvant chemotherapy may improve the OS of patients with OSCC.

Elevated Platelet Count Predicts Poor Prognosis in Breast Cancer Patients with Supraclavicular Lymph Node Metastasis

Background

More and more studies show that platelets are closely related to the occurrence and development of tumors. This study aims to explore the predictive value of peripheral blood platelet count on the prognosis of breast cancer patients with ipsilateral supraclavicular lymph node (ISLN) metastasis.

Methods

Eighty-five breast cancer patients with ISLN metastasis in the Affiliated Cancer Hospital of Zhengzhou University were collected retrospectively in this study. Chi-square test was used to analyze the correlation between clinical pathological data and platelet count. DFS rate was estimated by K-M curve and Log Rank test was performed. Univariate and multivariate Cox regression were used to determine the prognostic value of platelets. Time-dependent Cox regression was used to further analyze the correlation between peripheral blood platelets and prognosis to determine the stability of the results.

Results

The pathological complete response rate of ISLN after neoadjuvant chemotherapy (NAC) was 51.8%. Platelet count was correlated with PR status of breast cancer at first visit (P=0.01). After a median follow-up of 30 months, multivariate Cox analysis showed that high platelet count (HR=3.18, 95% CI=1.13–8.93, P=0.028), premenopausal status (HR=0.40, 95% CI=0.17–0.97, P=0.043), and ISLN pathological failure (HR=0.25 95%, CI=0.10–0.62, P<0.01) were associated with poor prognosis. K-M curve analysis showed that the prognosis of patients with a high platelet count was worse than that of patients with low platelet count (HR=5.32, 95% CI=2.41–11.75, P<0.01). To further verify the stability of this result, multivariate time-dependent Cox model also suggested that higher platelet level was related to poor prognosis (HR=1.009, 95% CI=1.003–1.016, P<0.01). Meanwhile, menopausal status (HR=0.32, 95% CI=0.14–0.76, P=0.01) and sPCR (HR=0.29, 95% CI=0.12–0.70, P=0.01) were also independent predictors of DFS.

Conclusion

Platelets have important predictive value for the prognosis of breast cancer patients with ISLN metastasis, which indicates that platelet count can be used to distinguish high-risk patients so as to obtain clinical benefits.

Combined PLT and NE to predict the prognosis of patients with locally advanced cervical cancer

Cervical cancer is one of the most common tumors in women. Neutrophils (NEs) and platelets (PLTs) are components of cells in circulating blood. NEs are one of the components of white blood cells (WBCs), accounting for the vast majority of WBCs, recognized as one of the indicators of inflammation. PLTs are associated with thrombosis and inflammation. Both of them play an important role in tumor growth and metastasis. According to pre-radiotherapy PLT and NE media levels, we divided the patients into three groups: PLT and NE both high levels group, single high level group and both low group. By using COX regression models and nomogram, a prognostic model for patients was established. Both high levels of pre-radiotherapy PLT and NE group or high levels of post-radiotherapy PLT and NE group were correlated with worst overall survival (OS) compared with the other two groups. PLT and NE were correlated with outcomes of the patients with locally advanced cervical cancer.

The combination of platelet count and lymphocyte to monocyte ratio is a prognostic factor in patients with resected breast cancer

Many inflammation indicators have been reported to be related with patient outcomes in various cancers. Previous studies have evaluated the combination of platelet (PLT) and lymphocyte to monocyte ratio (COP-LMR) as a systemic inflammatory marker for prognostication in lung cancer, yet its prognostic role among breast cancer patients remains unclear.In the present study, a total of 409 breast cancer patients with surgical resection were retrospectively investigated. The receiver operating characteristic (ROC) curve was used to choose the optimal cut-off value of PLT and lymphocyte to monocyte ratio (LMR). Patients were classified into 3 groups according to the score of COP-LMR, and its relationship with various clinicopathological factors and breast cancer prognosis were further evaluated.The ROC curve analysis showed that COP-LMR had a higher area under the ROC curve for the prediction of 5-year disease-free survival and overall survival than PLT or LMR alone. Multivariable analysis showed that an elevated COP-LMR was an independent predictor of poor disease-free survival (P = .032) and overall survival (P = .005). Subgroup analysis revealed that COP-LMR was still significantly associated with prognosis in both luminal A and luminal B subtypes.Preoperative COP-LMR is a potential prognostic factor in breast cancer patients who underwent surgery.

Motivation for Launching a Cancer Metastasis Inhibition (CMI) Program

Metastatic cancers impose significant burdens on patients, affecting quality of life, morbidity, and mortality. Even during remission, microscopic metastases can lurk, but few therapies directly target tumor cell metastasis. Agents that interfere with this process would represent a new paradigm in cancer management, changing the 'waiting game' into a time of active prevention. These therapies could take multiple forms based on the pathways involved in the metastatic process. For example, a phenome-wide association study showed that a single nucleotide polymorphism in the gene TBXA2R is associated with increased metastasis in multiple primary cancers (P = 0.003), suggesting clinical applicability of TBXA2R antagonists. Emerging data related to the role of platelets in metastasis are concordant with our sense that these pathways present significant opportunities for therapeutic development. However, before real progress can be made toward clinical targeting of the metastatic process, foundational work is needed to define informative measures of critical elements such as circulating tumor cells and tumor DNA, and circulatory vs. lymphatic spread. These challenges require an expansion of team science and composition to obtain competitive funding. At our academic medical center, we have implemented a Cancer Metastasis Inhibition (CMI) program investigating this approach across multiple cancers.

Elevated platelet distribution width predicts poor prognosis in hepatocellular carcinoma

BACKGROUND

Previous studies have demonstrated that platelets play an important role in growth, invasion, and angiogenesis of a variety of tumors. Nevertheless, the prognostic role of platelet indices in hepatocellular carcinoma (HCC) has not been explored. The aim of this study was to explore the association between platelet indices and prognosis in HCC.

METHOD

A total of 260 patients with HCC between January 2009 and December 2015 were retrospectively analyzed. The optimal platelet distribution width (PDW) cutoff value is identified by the receiver operating characteristic curve (ROC) curve. The relationship between PDW and clinicopathological features was assessed. The prognostic effects of PDW were assessed by using the Kaplan-Meier method and Cox regression model.

RESULT

Elevated PDW level was significantly associated with portal hypertension, vascular invasion, and Child-Pugh grade. In addition, survival curve indicates that patients with high PDW levels have a worse prognosis than patients with low PDW levels (P< 0.001). Multivariate Cox regression analysis identified PDW as an independent factor of prognosis in HCC patients (hazard ratio: 4.460, 95% confidence interval: 2.308-8.619, P< 0.001).

CONCLUSION

Elevated PDW may be a novel marker for predicting the prognosis of HCC, but further research is needed to validate our conclusions.

Comparison of clinical utilities of the platelet count and platelet-lymphocyte ratio for predicting survival in patients with cervical cancer: a single institutional study and literature review

Objective

To compare the clinical utilities of the platelet count and platelet-lymphocyte ratio (PLR) for predicting survival in patients with cervical cancer.

Results

Multivariate analyses demonstrated that thrombocytosis and elevated PLR were found to be independent prognostic factors for progression-free survival (PFS, P = 0.0077, P = 0.044) and overall survival (OS, P = 0.025, P = 0.019) in separate Multivariate analyses. In the ROC analysis, the platelet count showed a significantly greater area under the ROC curve (AUC) value than that of PLR for predicting patient recurrence (0.5941 versus 0.5331, p = 0.018) and survival (0.6139 versus 0.5468, p = 0.029). In patients without thrombocytosis, elevated PLR correlated with shorter survival (PFS, P = 0.041; OS, P = 0.017). In contrast, PLR in patients with thrombocytosis did not provide prognostic information. We divided patients into 3 prognostic groups using platelet counts and PLR: high-risk (thrombocytosis with any PLR); intermediate-risk (elevated PLR without thrombocytosis); low-risk (none of the above), which allowed for individualized and accurate survival estimates.

Materials and Methods

The baseline characteristics and clinical outcomes of cervical cancer patients were identified. Patients were grouped according to their pretreatment platelet counts or PLR, and clinicopathological characteristics and patient survival were then compared between these groups. The clinical utilities of the platelet count and PLR were compared using a time-dependent receiver operating characteristic (ROC) analysis.

Conclusions

Pretreatment thrombocytosis and elevated PLR were identified as independent predictors in cervical cancer patients. Platelet counts were superior to PLR for predicting the prognosis of uterine cervical cancer patients. Our prognostic model consisting of platelet counts and PLR offers individualized survival estimates.

Effectiveness of four inflammatory markers in predicting prognosis in 2374 women with breast cancer

OBJECTIVE

To analyze the association between four biomarkers and overall survival in patients with breast cancer (BC).

METHODOLOGY

This cohort study had a sample of 2374 women over the age of 18, diagnosed and treated in a single reference center for BC in Brazil, during the year 2008-2009. The following pretreatment indices were analyzed: neutrophil-lymphocyte ratio (NLR), a derived neutrophil-lymphocyte ratio (dNLR), absolute neutrophil count (ANC) and platelet-lymphocyte ratio (PLR). A descriptive analysis was performed using median (range) and absolute and relative frequency as categorical variables. Exploratory survival evaluation was performed using the Kaplan-Meier method and the log-rank test for comparison between survival curves, with a statistical significance level of 5%. The variables with p<0.20 were selected for inclusion in a multivariate Cox regression model, considering as statistically significant p<0.05.

RESULTS

After adjusting for clinical variables, the biomarkers associated with worse overall survival were NLR >5 (HR=1.66 95%CI 1.08-2.55; p=0.021) and PLR >300 (HR=1.82 95%CI 1.10-2.99; p=0.019). When stratified by molecular subtype, the independent markers related to death were PLR >300 for triple negative (HR 3.27 95%CI 1.38-7.76; p=0.007); NLR >5 (HR 2.47 95%CI 1.16-5.28; p=0.019), ANC >7500 (HR 1.84 95%CI 1.17-2.90; p=0.008) and dNLR >3 (HR 2.45 95%CI 1.29-4.66; p=0.006) for luminal.

CONCLUSION

NLR and PLR are independent markers of prognosis in BC. Further studies are needed in patients with overexpression of HER 2.

The pretreatment thrombocytosis may predict prognosis of patients with colorectal cancer: a systematic review and meta-analysis

AIM

Recently, several studies have reported that thrombocytosis may be associated with the poor prognosis of colorectal cancer (CRC). Nevertheless, their conclusions were still controversial. Results & methodology: We searched PubMed, Embase, Cochrane Library and Web of Science up to April 2016. A total of 30 studies including 9129 patients were included in this meta-analysis. Thrombocytosis had a close relationship with the poor overall survival of CRC compared with normal platelet counts, with the pooled hazard ratios being 1.89 (95% CI: 1.45-2.47; p < 0.00001) and 1.83 (95% CI: 1.33-2.53; p = 0.0002), with univariate and multivariate analyses, respectively.

DISCUSSION & CONCLUSION

This meta-analysis indicated that thrombocytosis may be a cost-effective and noninvasive indicator for poor prognosis of patients with CRC, especially for overall survival.

Safety and Efficacy of Trastuzumab Emtansine in Advanced Human Epidermal Growth Factor Receptor 2-Positive Breast Cancer: a Meta-analysis

Advanced or metastatic breast cancer is an incurable disease with high mortality rate worldwide and about 20% of breast cancers overexpress and amplify the human epidermal growth factor receptor 2 (HER2). Achievements in targeted therapy have benefited people during the past decades. Trastuzumab emtansine (T-DM1), a novel antibody-drug conjugate playing a powerful role in anti-tumor activity, not only blocks the HER2 signaling pathways, but also disturbs the microtubule dynamics. To access the efficacy and safety of T-DM1, we analyzed 9 clinical trials on T-DM1. Results showed that fatigue (0.604, 95% CI 0.551, 0.654), nausea (0.450, 95% CI 0.365, 0.537), increased transaminases (0.425, 95% CI 0.353, 0.500) and thrombocytopenia (0.383, 95% CI 0.322, 0.448) occurred more frequently in participants with single T-DM1. In controlled trials, increased transaminases (OR = 4.040, 95% CI 1.429, 11.427), thrombocytopenia (OR = 8.500, 95% CI 3.964, 18.226) and fatigue (OR = 1.288, 95% CI 1.041, 1.593) were statistically significant. Only thrombocytopenia appeared as severe adverse event (grade ≥ 3) in single-arm and control-arm studies. Meanwhile, T-DM1 stabilized cancer and prolonged life with notable improved progression-free survival (PFS) and overall survival (OS). In conclusion, it is a safe and effective agent in advanced or metastatic breast cancer, but should be carefully applied on patients with severe hepatic and neurological disease.