Clinical and Prognostic Features of Erionite-Induced Malignant Mesothelioma

Abstract

This review analytically examines the published data for erionite-related malignant pleural mesothelioma (E-MPM) and any data to support a genetically predisposed mechanism to erionite fiber carcinogenesis. Adult patients of age ≥18 years with erionite-related pleural diseases and genetically predisposed mechanisms to erionite carcinogenesis were included, while exclusion criteria included asbestos- or tremolite-related pleural diseases. The search was limited to human studies though not limited to a specific timeframe. A total of 33 studies (31042 patients) including 22 retrospective studies, 6 prospective studies, and 5 case reports were reviewed. E-MPM developed in some subjects with high exposures to erionite, though not all. Chest CT was more reliable in detecting various pleural changes in E-MPM than chest X-ray, and pleural effusion was the most common finding in E-MPM cases, by both tests. Bronchoalveolar lavage remains a reliable and relatively less invasive technique. Chemotherapy with cisplatin and mitomycin can be administered either alone or following surgery. Erionite has been the culprit of numerous malignant mesothelioma cases in Europe and even in North America. Erionite has a higher degree of carcinogenicity with possible genetic transmission of erionite susceptibility in an autosomal dominant fashion. Therapeutic management for E-MPM remains very limited, and cure of the disease is extremely rare.

Different Erionite Species Bind Iron into the Structure: A Potential Explanation for Fibrous Erionite Toxicity

“…Interestingly, Ballirano et al [48] showed that both erionite-Na from Rome (OR, USA) and woolly erionite-K from Durkee (OR, USA) could fix Fe(II) into the structure through ion-exchange involving mainly Na. Further, the amount of Fe(II) bound by sample in this study [330 (20) nmol/mg] is comparable with that acquired, under the same experimental conditions, by erionite-Na from Rome (OR, USA) [262(1) nmol/mg]. These data are relevant considering the reported higher selectivity of erionite for Ca with respect to Na [68,69], and provide evidence of a strong tendency of Fe(II) to enter the erionite structure, due to its relatively high ionic potential, which exceeds that of the common extra-framework cations [50].…”

“…Inhalation of fibrous erionite has shown to be correlated with diseases like those already known from exposure to asbestos [14,15]. In particular, high rates of malignant mesothelioma were reported, since the 1970s, in three villages of Cappadocia, Turkey [16][17][18][19][20]. In vivo and in vitro studies indicated that fibrous erionite is significantly more tumorigenic than chrysotile asbestos and amphibole asbestos [21][22][23][24][25][26].…”

Epidemiology of Environmental Exposure and Malignant Mesothelioma

“…There were five cohort studies that investigated cases of MM survival. 30,33,34,59,60 Nine studies used a case-control design, 29,[33][34][35][36]44,51,60,64 two of which were nested case-control studies. 44,60 There were two risk assessment studies that used modeling approaches to estimate MM mortality 58 and incidence.…”

Erionite Studies in Custer National Forest

“…Average annual precipitation is around 15 inches (380 mm). (101) There is an average of 19.7 days per year with at least 0.01 inches of precipitation according weather data collected from 1981 to 2010 from the NOAA National Climatic Data Center. (104) According to the 2010 U.S. Census Bureau, Harding County has a total area of 2,678 square miles and a population of 1,255.…”

“…Erionite is an acicular zeolite and it has been shown that people exposed to erionite have a higher risk to develop malignant mesothelioma (MM) than people exposed to all the other mineral fibers that are currently exposure regulated in the United States. (101) Although erionite does not have the same extensive and various commercial applications as the other regulated asbestos fibers and is rarely found in the environment, disturbance of natural-occurring erionite at specific sites may generate airborne fibers with similar or even worse health effects as the well-known asbestos fibers.…”