Robust data: the essential foundation of a revised staging system for pleural mesothelioma

Establishment of predictive nomogram and web-based survival risk calculator for malignant pleural mesothelioma: A SEER database analysis

Background

Malignant pleural mesothelioma (MPM) is an uncommon condition with limited available therapies and dismal prognoses. The purpose of this work was to create a multivariate clinical prognostic nomogram and a web-based survival risk calculator to forecast patients’ prognoses.

Methods

Using a randomization process, training and validation groups were created for a retrospective cohort study that examined the Surveillance, Epidemiology, and End Results (SEER) database from 2010 to 2015 for individuals diagnosed with MPM (7:3 ratio). Overall survival (OS) and cancer-specific survival (CSS) were the primary endpoints. Clinical traits linked to OS and CSS were identified using Least Absolute Shrinkage and Selection Operator (LASSO) Cox regression analysis, which was also utilized to develop nomogram survival models and online survival risk calculators. By charting the receiver operating characteristic (ROC), consistency index (C-index), calibration curve, and decision curve analysis (DCA), the model’s performance was assessed. The nomogram was used to classify patients into various risk categories, and the Kaplan-Meier method was used to examine each risk group’s survival rate.

Results

The prognostic model comprised a total of 1978 patients. For the total group, the median OS and CSS were 10 (9.4-10.5) and 11 (9.4-12.6) months, respectively. As independent factors for OS and CSS, age, gender, insurance, histology, T stage, M stage, surgery, and chemotherapy were chosen. The calibration graphs demonstrated good concordance. In the training and validation groups, the C-indices for OS and CSS were 0.729, 0.717, 0.711, and 0.721, respectively. Our nomogram produced a greater clinical net benefit than the AJCC 7th edition, according to DCA and ROC analysis. According to the cut-off values of 171 for OS and 189 for CSS of the total scores from our nomogram, patients were classified into two risk groups. The P-value < 0.001 on the Kaplan-Meier plot revealed a significant difference in survival between the two patient groups.

Conclusions

Patient survival in MPM was correctly predicted by the risk evaluation model. This will support clinicians in the practice of individualized medicine.

The eighth TNM classification for malignant pleural mesothelioma

In 2016, the International Association for the Study of Lung Cancer (IASLC) published a number of revisions of the seventh edition of the tumor, node and metastasis (TNM) classification for malignant pleural mesothelioma (MPM). The purpose was to establish a set of recommendations for the eighth edition of the TNM staging system. A large number of patients were included in the IASLC database and subsequently analysed to determine new definitions for the components of the TNM classification. A number of important changes were introduced for the T component. Survival analysis of the different T categories showed no significant difference in categories T1a and T1b. This has resulted in a collapse of categories T1a and T1b into one category T1. In addition, tumor thickness was also significantly associated with overall survival. The descriptors for the N components have been redefined as well for the eighth TNM classification. A major revision is the removal of category N3 in the N component. Both intrapleural and extrapleural (N1 and N2 in the seventh edition) are now combined into a single category N1. Lymph nodes that were previously categorized as N3 are now considered N2. For the M component, no redefinition has been published. However, a recommendation has been made to only consider M1 involvement as stage IV disease. This is in contrast to the seventh edition in which T4 and N3 disease were considered stage IV as well. In conclusion, a number of important revisions for the eighth TNM classification of MPM have been published as a result of this IASLC project. This type of large-scale and international joint efforts are key in establishing effective staging systems. Research into using tumor thickness as a prognostic instrument will be an important part of any future editions of the TNM classification.

The revised staging system for malignant pleural mesothelioma based on surveillance, epidemiology, and end results database

BACKGROUND

Several staging systems for MPM have been introduced. However, none of them provide perfect survival stratification among heterogeneous patients. The aim of this population-based cohort study was to propose adjustments to current staging system for malignant pleural mesothelioma (MPM).

METHODS

We retrieved MPM data from Surveillance, Epidemiology, and End Results database (1973-2014). Kaplan-Meier method was derived to examine the prognostic effects of tumor, lymph node, metastasis and histology features. Proportional hazards models guided adjustments to stage groupings. The accuracy of staging systems at predicting survival was evaluated by concordance index and bootstrap resampling.

RESULTS

A total of 1110 MPM cases were extracted from SEER. T stage failed to demonstrate survival difference between adjacent categories with the exception of T3 versus T4 (P < 0.001). Patients in M0 had better prognosis than those in M1 (P < 0.001). Exploratory analyses suggested important survival difference for single-versus multiple-site M1 cases (P < 0.001), but not for different metastatic sites (P = 0.286). Histology subtype was a significant prognostic indicator (P < 0.001). Regrouping of TNM and histology combinations resulted in the best concordance index (0.683), compared with UICC 2010 (0.578) and IASLC 2016 (0.585) staging systems. The revised staging system also improved patients distribution (IA:33.8%, IB:17.0%, II: 20.7%, IIIA:10.6%, IIIB: 6.8%, IV:11.1%). Log-rank analyses and calibration plots both demonstrated the new stage achieved optimal survival prediction and discrimination.

CONCLUSION

The revised staging system improved patients distribution and survival stratification for MPM.

A review of bevacizumab in the treatment of malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is an aggressive cancer with poor prognosis. Systemic chemotherapy is the primary treatment modality for the majority of patients. VEGF plays a key mitogen for MPM cells physiopathology. Bevacizumab, a monoclonal anti-VEGF antibody, was a rational approach to be tested in MPM. Based on the results of the Phase III IFCT-0701 mesothelioma avastin cisplatin pemetrexed study, cisplatin-pemetrexed-bevacizumab is now the accepted standard in France. The National Comprehensive Cancer Network guidelines have also included this combination as an option for standard front-line therapy. This review summarized the efficacy and safety data of bevacizumab in the treatment of patients with MPM.

Diagnostic tools and staging of malignant pleural mesothelioma

The diagnosis of malignant pleural mesothelioma remains challenging and should be based on both histologic evidence of invasion and immunohistochemical findings supportive of mesothelioma. Cytology is a controversial method of diagnosis, but may be a useful tool, particularly in the identification of other metastatic malignancies. Malignant pleural mesothelioma must be differentiated from benign, reactive mesothelial proliferations and other metastatic malignancies. Histologic analysis in conjunction with immunohistochemistry, electron microscopy, and limited molecular diagnostics are most useful in establishing a diagnosis. The staging of malignant pleural mesothelioma is most commonly performed using a TNM (tumor, node, metastasis) system proposed by the International Mesothelioma Interest Group.

Sarcomatoid mesothelioma: future advances in diagnosis, biomolecular assessment, and therapeutic options in a poor-outcome disease

Malignant pleural mesothelioma (MPM) is the most frequent pleural neoplasm, with asbestos exposure as one of the recognized carcinogen agents, causative in 80% of cases. The prognosis is poor; median survival of untreated cases is 6-9 months, with fewer than 5% of patients surviving 5 years. Sarcomatoid mesothelioma (SM) represents the subtype with the worst outcome and median survival ranging from 3.5 to 8 months. In the last few years, an accurate differentiation between the subtypes of MPM has become a crucial issue, due to differences in chemosensitivity and clinical outcome, and several studies have evaluated different immunohistochemical markers to better define the diagnosis. The different and worse outcome of patients with SM and, in general, nonepithelioid subtypes makes it intriguing to select these cases to better study the biomolecular profile in order to find factors linked to prognosis and/or predictive of therapeutic response. Considering recent studies on miRNA and genetic mapping, further investigation of this rare subtype might represent a field for basic and clinical-translational research providing for more tailored therapies.

Stratification of malignant pleural mesothelioma prognosis using recursive partitioning analysis

PURPOSE

Prognostic factors and complicated prognostic models have been proposed for malignant pleural mesothelioma (MPM). This study was designed to stratify MPM prognosis by using a simple model.

METHODS

Patients diagnosed with MPM in the past 10 years (n = 122) were examined retrospectively. Data on the presence of chest pain, performance status (PS), asbestos exposure, smoking status, white blood cell count (WBC), haemoglobin (Hb) concentration, platelet count (PLT), lactate dehydronate (LD), histology, stage, and date of death or censored status were collected. After the factors were examined in the univariate analysis, recursive partitioning analysis was performed.

RESULTS

Statistically significant factors related to survival were the type of histology, stage, PS, WBC, PLT, Hb concentration, and LD. Histology, stage, PS, and Hb concentration were used in multivariate analysis. Stage and Hb concentration showed good statistical significance, whereas PS was borderline significant. The survival analyses were stratified into five groups by PS, stage, Hb concentration, and chest pain using recursive partitioning analysis. Group A comprised patients showing the most favourable prognoses (PS 0-2 and Hb concentration >12.1 g dL(-1) or PS 0-2 and Hb concentration ≤12.1 g dL(-1) without pain), and group B comprised the remaining patients. The median overall survival in groups A and B was 563 days (95 % confidence interval [CI] 502-779) and 157 days (95 % CI 115-224), respectively (hazard ratio of 5.44 [3.46-8.53, P < 0.0001]).

CONCLUSIONS

The MPM patients with PS 0-2 and Hb concentration >12.1 or ≤12.1 g dL(-1) without chest pain had favourable prognoses.