Malignant mesothelioma: current status and perspective in Japan and the world

Multi-institutional survey of malignant pleural mesothelioma patients in the Hokushin region

BACKGROUND

Malignant pleural mesothelioma (MPM) is a major occupational and environmental neoplasm. The purpose of this study was to validate the clinical and epidemiological factors, diagnosis, and initial treatment among MPM patients in the Hokushin region.

METHODS

We surveyed retrospective data from 152,921 cancer patients in 22 principal hospitals.

RESULTS

A total of 166 MPM cases were newly diagnosed. These patients consisted of 136 men and 30 women, with a median age of 69 years. We estimated the incidence rate for MPM to be 0.55 cases per 100,000 person-years in this study. The ratio per 100,000 population-years was 0.39 in Fukui, 0.60 in Ishikawa, 1.02 in Toyama and 0.35 in Nagano. Forty-five patients were discovered when diagnosed incidentally in patients under observations for other diseases. Forty-six cases were diagnosed as localized disease, while 13 had accompanying regional lymph node metastasis. Furthermore, 44 cases showed infiltration into adjacent organs. A histo-cytological diagnosis was made in 164 cases (98.8%). A surgical approach, chemotherapy, and radiotherapy were performed for 33, 88, and 6 patients, respectively, while 44 patients (26.5%) received best supportive care. Multimodality therapy was conducted in just 3.0% of the MPM patients CONCLUSION: MPM has a tragically rapid progression if discovered under observations for other diseases. Workers in health-related fields should be on high alert for aggressive MPM. Better evaluation and multi-disciplinary approaches to MPM in these regions are needed to optimize multimodality therapy.

Japanese Current Status of Curative-Intent Surgery for Malignant Pleural Mesothelioma

BACKGROUND

Few reports about surgical outcomes in malignant pleural mesothelioma (MPM) were based on reliable nationwide databases. Here we analyzed the incidence, surgical outcome, and operative risk factors using Japanese nationwide database.

METHODS

Characteristics and perioperative data from 622 patients who underwent curative-intent surgery for MPM between January 2014 and December 2017 were recorded from National Clinical Database of Japan. We analyzed the incidence, surgical outcomes, and risk factors for surgical complications after two surgical procedures (extrapleural pneumonectomy, EPP; and pleurectomy/decortication, P/D).

RESULTS

During 4 years, EPP was performed in 279 patients and P/D in 343. EPP was more frequently performed in less-MPM-experienced institutions, while P/D was more frequently performed in well-MPM-experienced institutions (P < .001), especially in high-volume centers with more than 10 cases during this period. P/D was more frequently performed, especially in high-volume centers. The morbidity rates were 45.2% in EPP and 35.9% in P/D. Heart failure and pneumonia were most frequent in EPP, while prolonged air leakage was most frequent in P/D. Thirty-day- and in-hospital mortality rates were 1.1% and 3.2% (EPP) and 1.2% and 3.2% (P/D), respectively. Regression analyses revealed that higher age (>65 years) was associated with operative complications in EPP (odds ratio, OR: 3.56 [1.26-8.56]), whereas no risk factor was observed in P/D.

CONCLUSIONS

In Japanese nationwide annual database, P/D was more frequently performed, especially in high-volume centers. Morbidity was higher in EPP than P/D; however, the mortality rates were quite low in Japan regardless surgical procedures.

Malignant Pleural Mesothelioma with Bone Marrow Metastases

A 64-year-old man with the bone marrow metastasis due to malignant pleural mesothelioma (MPM) was diagnosed with anemia, leukoerythroblastosis, thrombocytopenia, and lower back pain. A bone marrow biopsy demonstrated infiltrative malignant mesothelioma lesions in the bone marrow. The patient died within 15 days of the detection of the bone marrow involvement. Physicians should consider performing a bone marrow biopsy to diagnose bone marrow metastasis and treat patients with palliative chemotherapy at an earlier phase of the disease. To our knowledge, this is the first report of an MPM patient having bone marrow metastasis with anemia, leukoerythroblastosis, and thrombocytopenia.

Malignant pleural mesothelioma: diagnostic value of medical thoracoscopy and long-term prognostic analysis

BACKGROUND

Malignant pleural mesothelioma (MPM) is marked by its difficult diagnosis and poor prognosis. Medical thoracoscopy (MT) is an effective and safe procedure for the diagnosis of exudative pleural effusions and many factors associated with poor prognosis of MPM. We conducted this study to investigate the value of MT for diagnosing of MPM and to identify prognostic factors for MPM patients.

METHODS

From July 2005 through June 2014, a total of 833 patients with undiagnosed pleural effusions underwent MT and pleural biopsies were taken. Clinical data of all patients with MPM were retrospectively analyzed, and those with complete follow-up data were analyzed for prognostic factors.

RESULTS

Eventually, MPM was the final diagnosis in 40 patients. Diagnostic efficiency of MT for MPM was 87.5%, since diagnosis of MPM failed to be established in 5 patients during the initial MT. Median survival was 17.1 mo (95% confidence interval: 13.6-20.7 mo). MT findings of pleural adhesion and plaques were adverse prognostic factors for MPM. In addition, old age, male gender, smoking history, histological type, poor staging, no treatment, low total protein level in pleural fluid, and computed tomographic findings such as pulmonary consolidation or infiltration, mediastinal lymphopathy, pulmonary mass or nodules, and pleural nodularity were also poor prognostic factors for MPM.

CONCLUSIONS

MT is safe with a high positive rate in the diagnosis of MPM, and pleural adhesion and plaques seen under MT may be the adverse prognostic factors for MPM. Multiple clinical characteristics can affect the survival of MPM patients.

Prospective registry database of patients with malignant mesothelioma: directions for a future Japanese registry-based lung cancer study

Background

The International Association for the Study of Lung Cancer, in collaboration with members of the International Mesothelioma Interest Group (IMIG), developed a large international database and TNM-based system to study malignant pleural mesothelioma (MPM). However, this database has some limitations since it was a retrospective study and it was based predominantly on surgical cases. The Japanese Joint Committee of Lung Cancer Registry (JJCLCR) employs a project of prospective registry database of patients in Japan with MPM in order to clarify MPM's epidemiology, current management practices, and prognosis and also to investigate the potential capabilities to target the best patients for therapy.

Methods

Tumor stage is described using the 7th and 8th versions of IMIG staging system. This prospective cohort study has been conducted from April 1, 2017 to March 31, 2019.

Discussion

We will analyze the data in this registry to determine the most recent outcomes and trends related to MPM treatment in Japan. The present prospective study is expected to validate the 8th version of IMIG staging system, and to investigate whether tumor thickness is a reliable T-descriptor.

Trial registration

ClinicalTrials.gov Identifier: UMIN 000024664.

Extrapleural pneumonectomy or pleurectomy/decortication for malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is associated with a very poor prognosis. Unlike other solid tumors, any type of planned surgery for MPM would be cytoreductive rather than radical. There are two types of surgery for MPM. Extrapleural pneumonectomy (EPP) involves en bloc resection of the lung, pleura, pericardium, and diaphragm. Pleurectomy/decortication (P/D) is a lung-sparing surgery that removes only parietal/visceral pleura. In comparison with EPP, P/D is theoretically less radical but is associated with less perioperative mortality/morbidity and less postoperative deterioration of cardiopulmonary function. It still remains unclear which surgical technique is superior in terms of the risk/benefit ratio. In this context, selection between EPP and P/D has been a matter to debate.

A feasibility study of induction pemetrexed plus cisplatin followed by pleurectomy/decortication aimed at macroscopic complete resection for malignant pleural mesothelioma

A prospective multi-institutional study has been initiated in Japan to evaluate the feasibility of induction chemotherapy using pemetrexed plus cisplatin, followed by pleurectomy/decortication aimed at macroscopic complete resection in patients with resectable malignant pleural mesothelioma. The study was initiated on September 2012, for which 24 patients will be recruited over a period of 2 years. The primary endpoint is the macroscopic complete resection rate, regardless of the surgical technique employed (i.e. pleurectomy/decortication or extrapleural pneumonectomy). The secondary endpoints are the pleurectomy/decortication rate, macroscopic complete resection rate by pleurectomy/decortication, pulmonary function at 3 months after surgery, adverse events, treatment-related mortality, response rate to chemotherapy and 3-year overall survival rate.

Increased circulating miR-625-3p: a potential biomarker for patients with malignant pleural mesothelioma

INTRODUCTION

We investigated the ability of cell-free microRNAs (miRNAs) in plasma and serum to serve as a biomarker for malignant mesothelioma (MM).

METHODS

Using miRNA microarrays, we profiled plasma samples from MM patients and healthy controls. miRNAs with significantly different abundance between cases and controls were validated in a larger series of MM patients and in an independent series of MM patients using quantitative real-time polymerase chain reaction. Levels of candidate miRNAs were also quantified in MM tumor samples.

RESULTS

We compared cell-free miRNA profiles in plasma from MM patients with healthy controls. Reviewing 90 miRNAs previously reported to be associated with MM, we found that the levels of two miRNAs, miR-29c* and miR-92a, were elevated in plasma samples from MM patients. In addition, we identified 15 novel miRNAs present at significantly higher levels in the plasma of MM patients. Further analysis of candidate miRNAs by real time-quantitative polymerase chain reaction confirmed that one of them, miR-625-3p, was present in significantly higher concentration in plasma/serum from MM patients and was able to discriminate between cases and controls, in both the original and the independent series of patients. MiR-625-3p was also found to be up-regulated in tumor specimens from a group of 18 MM patients, who underwent extrapleural pneumonectomy.

CONCLUSION

Our data confirm the potential of miR-29c* and miR-92a as candidate tumor markers and reveal that miR-625-3p is a promising novel diagnostic marker for MM.

A case report of an extremely rare and aggressive tumor: primary malignant pericardial mesothelioma

Primary pericardial malignant mesothelioma (PMPM) is extremely rare with an incidence less than 0.0022%. It comprises 0.7% of all mesothelioma cases. To date, approximately 350 cases of pericardial mesothelioma have been reported in the literature. Its typical presentation is insidious, with nonspecific signs and symptoms, and usually results in constrictive pericarditis, cardiac tamponade and congestive heart failure either by a serous effusion or by direct tumorous constriction of the heart. With the exception of several case reports, the outcome is uniformly fatal, and patients typically die within six months of diagnosis. Here we report a 72-year-old Cauca -sian male with persistent pericardial and pleural effusion. He was diagnosed with PMPM after pericardectomy. He had only one cycle of chemotherapy with cisplatin and pemetrexed. He developed acute kidney injury as result of chemotherapy. He died 1 month after diagnosis and 6 months after the first symptoms.

Asbestos-induced cellular and molecular alteration of immunocompetent cells and their relationship with chronic inflammation and carcinogenesis

Asbestos causes lung fibrosis known as asbestosis as well as cancers such as malignant mesothelioma and lung cancer. Asbestos is a mineral silicate containing iron, magnesium, and calcium with a core of SiO₂. The immunological effect of silica, SiO₂, involves the dysregulation of autoimmunity because of the complications of autoimmune diseases found in silicosis. Asbestos can therefore cause alteration of immunocompetent cells to result in a decline of tumor immunity. Additionally, due to its physical characteristics, asbestos fibers remain in the lung, regional lymph nodes, and the pleural cavity, particularly at the opening sites of lymphatic vessels. Asbestos can induce chronic inflammation in these areas due to the production of reactive oxygen/nitrogen species. As a consequence, immunocompetent cells can have their cellular and molecular features altered by chronic and recurrent encounters with asbestos fibers, and there may be modification by the surrounding inflammation, all of which eventually lead to decreased tumor immunity. In this paper, the brief results of our investigation regarding reduction of tumor immunity of immunocompetent cells exposed to asbestos in vitro are discussed, as are our findings concerned with an investigation of chronic inflammation and analyses of peripheral blood samples derived from patients with pleural plaque and mesothelioma that have been exposed to asbestos.

Asbestos induces reduction of tumor immunity

Asbestos-related cancers such as malignant mesothelioma and lung cancer are an important issue in the world. There are many conflicts concerning economical considerations and medical evidence for these cancers and much confusion regarding details of the pathological mechanisms of asbestos-induced cancers. For example, there is uncertainty concerning the degree of danger of the iron-absent chrysotile compared with iron-containing crocidolite and amosite. However, regarding bad prognosis of mesothelioma, medical approaches to ensure the recognition of the biological effects of asbestos and the pathological mechanisms of asbestos-induced carcinogenesis, as well as clinical trials to detect the early stage of mesothelioma, should result in better preventions and the cure of these malignancies. We have been investigating the immunological effects of asbestos in relation to the reduction of tumor immunity. In this paper, cellular and molecular approaches to clarify the immunological effects of asbestos are described, and all the findings indicate that the reduction of tumor immunity is caused by asbestos exposure and involvement in asbestos-induced cancers. These investigations may not only allow the clear recognition of the biological effects of asbestos, but also present a novel procedure for early detection of previous asbestos exposure and the presence of mesothelioma as well as the chemoprevention of asbestos-related cancers.

[Current status and future direction of Japan's clinical trial for malignant pleural mesothelioma]

The feasibility and efficacy of trimodality therapy for malignant pleural mesothelioma (MPM) are still controversial mainly due to the lack of clinical evidence. Although three major clinical trials on this therapy have been recently reported from North America and Europe, it remains unclear whether results in Caucasian populations may be directly applicable to Asian populations. In this context, as a project of the "Comprehensive approach on asbestos-related diseases" supported by the "Special Coordination Fund for Promoting Science and Technology of MEXT, Japan", a prospective multi-institutional study has been planned to evaluate the feasibility of induction chemotherapy using pemetrexed plus cisplatin, followed by extrapleural pneumonectomy (EPP) and postoperative hemithoracic radiation in patients with resectable MPM. Primary endpoints are macroscopic complete resection rate by EPP and treatment-related mortality for trimodality therapy. The study was initiated in May 2008 and patient enrollment was finished in November 2010.

Survival and prognostic factors in malignant pleural mesothelioma: a retrospective study of 314 patients in the west part of Japan

OBJECTIVE

The objective in our study was to examine baseline and other characteristics associated with survival in patients with malignant pleural mesothelioma in Japan.

METHODS

Three hundred and fourteen patients with an adjudicated diagnosis of mesothelioma were examined. Survival was evaluated by the Kaplan-Meier method with the log-rank test. The Cox model was used to estimate the hazard ratio for the possible prognostic factors.

RESULTS

Of 314 patients, 223 (71%) died and only 40 (13%) were still alive at the end of the observation period starting from the day of diagnosis, while 51 (16%) were transferred to other hospitals or had the last health service contact before the end of the study period yielding the median survival of 308 days. In the multivariate analysis, age older than 70 years (hazard ratio = 2.17; 95% confidence interval, 1.36-3.46), non-epithelioid type (hazard ratio = 1.58; 95% confidence interval, 1.15-2.18), poor performance status (hazard ratio = 3.22; 95% confidence interval, 1.19-8.74), high white blood cell count (hazard ratio = 1.49; 95% confidence interval, 0.99-2.26) and high C-reactive protein level (hazard ratio = 1.80; 95% confidence interval, 1.06-3.06) were negatively associated with survival, after adjustment for other factors.

CONCLUSIONS

Some baseline conditions including old age, poor performance status, non-epithelioid type, high white blood cell count and high C-reactive protein level were determinants of poor survival of patients with malignant mesothelioma.