Primary pleural mesotheliomas in south India: a 25-year study

Cytological diagnosis of malignant mesothelioma: A case series

Background:

Mesotheliomas are neoplasms of the serosal lining of the body cavities. Diagnosis requires a multimodal approach of clinical findings, cytology, and histopathology with immunohistochemistry (IHC). The published sensitivity of cytology for diagnosing mesothelioma ranges from 30% to 75%.

Aim and Objectives:

This study aimed to calculate the incidence of malignant mesothelioma (MM) at our institute and to study the cytological features of MM.

Materials and Methods:

A retrospective study of pleural, peritoneal, and pericardial fluids submitted at our institute was done. The duration of the study was 8 years (2011–2019). Apart from examining Giemsa smears, a panel of immunocytochemical (ICC) and cell block immunohistochemical (IHC) markers was applied to achieve the diagnosis. These included calretinin, mesothelin, CK5/6, Hector Battifora mesothelial cell antibody (HBME), WT1, MOC31, CK7 and CK20. Histopathological correlation was done wherever possible.

Result:

In the present study, we compiled four cases of MM over 8 years diagnosed on serous effusion cytology and confirmed by immunocytochemistry (ICC)/cell block immunohistochemistry (IHC)/biopsy. This indicates a rare incidence of MM. The Cytological features of MM were studied.

Conclusion:

The diagnosis of MM is difficult, especially cytologically. It was found to be a rare entity in the malignant cases diagnosed on effusion cytology.

A case from India of pleural malignant mesothelioma probably due to domestic and environmental asbestos exposure: a posthumous report

India is the largest consumer of asbestos in the world. There is no report from India of mesothelioma related to asbestos. The case is a 42-year-old man who died of pleural mesothelioma. He was exposed to asbestos domestically and from the environment since birth. Two of his close family members worked in a factory that used asbestos. The living quarter of the family was within the premises of the factory. Asbestos waste was strewn on the grounds surrounding the quarters. After decades of legal battles by workers and families exposed to asbestos, Indian courts have ordered remedial measures and compensation to people, who are exposed to asbestos at work and the environment. Mesothelioma, currently in epidemic proportions in the west where asbestos production was banned in the 1990s, could rise to alarming levels in the next decades in India if the legal remedial measures are not implemented soon.

Malignant mesothelioma: A histomorphological and immunohistochemical study of 24 cases from a tertiary care hospital in Southern India

BACKGROUND

Malignant mesotheliomas are histologically heterogeneous neoplasms. Definite diagnosis requires a varied panel of immunohistochemical (IHC) markers to differentiate these from histological mimics. Only a few case series have been reported in the Indian literature where mesotheliomas have been analyzed on routine histology and IHC.

AIM

To evaluate the histological features of malignant mesothelioma and to elucidate the best possible immunomarker combination useful in different scenarios.

MATERIALS AND METHODS

A total of 24 cases of malignant mesotheliomas of different sites encountered over a 6-year period were retrospectively analyzed with regard to their histomorphology and IHC findings.

RESULTS

The pleura was the most common site of involvement (16 cases) followed by peritoneum (5 cases) and pericardium (3 cases). Epithelioid mesothelioma was the most common histological type (15 cases, 62.5%) followed by sarcomatoid (5 cases, 20.84%), deciduoid (2 cases, 8.34%), and 1 case each of desmoplastic and biphasic mesothelioma. Among the mesothelial markers, WT1 was positive in 17 of 20 (85%) cases and calretinin was positive in 20 of 21 (95.23%) cases. D2-40 and CK5/6 were positive in all cases where they were studied. Adenocarcinoma markers TTF-1, napsin A, and CEA had very high negative predictive value in ruling out mesothelioma.

CONCLUSION

The differential diagnosis of mesotheliomas varies with histological type and tumor location. Judicious use of various combinations of IHC markers in different situation has been highlighted in this article.

Global trends in mortality from malignant mesothelioma: Analysis of WHO mortality database (1994-2013)

BACKGROUND AND OBJECTIVE

Little is known about the extent to which asbestos use ban has affected global trends in malignant mesothelioma. This study investigated recent global mortality trends of malignant mesothelioma.

METHODS

Data were collected from International Agency for Research on Cancer/World Health Organization mortality database to examine age-standardized, gender-specific mortality rates for malignant mesothelioma (ICD10-C45). Cross-sectional mortality rates (2009-2013) as well as trends over time (1994-2013) were also reported. Gender-specific annual percent change (APC) was calculated to examine trends over time for each country.

RESULTS

Among the 30 countries with highest mesothelioma mortality in men, there is almost 10-fold variation in mortality rates during 2009-2013 ranging from 6.25 per 100 000 for United Kingdom to 0.64 per 100 000 in Portugal; whereas, among the 30 countries with highest mesothelioma mortality in women, there is a 4-fold variation in mortality rates during 2009-2013 ranging from 1.08 per 100 000 for United Kingdom to 0.26 per 100 000 in Ireland. Mortality rates were higher in men compared to women in 32 out of 35 evaluable countries. Among males and over the last 10 years of covered years, mesothelioma mortality was significantly declining in 9 countries (United Kingdom, Sweden, France, Germany, Netherlands, Canada, United States, Australia, and New Zealand); whereas, it was significantly rising in 5 countries (Poland, Spain, China-Hong Kong, Japan, and Republic of Korea). In the remaining countries, APC was stable. Among females and over the last 10 years of covered years, mesothelioma mortality was significantly declining in 1 country only (Italy); whereas, it was significantly rising in 3 countries (Poland, Argentina, and Republic of Korea). In the remaining countries, APC was stable.

CONCLUSIONS

There is a worldwide variability in the burden and trends of mesothelioma mortality; and despite the ban on asbestos in many countries, mesothelioma still represents an important cause of mortality.

Malignant pleural mesothelioma

Malignant mesothelioma is one of the rare tumors of pleura. One such case in a 57-year-old male, who presented with hemorrhagic pleural effusion and had no history of asbestos exposure, is reported here. The rarity, unusual presentation, and implications are discussed.

Asbestos ban in India: challenges ahead

Rapidly industrializing India is described by the International Monetary Fund as a young, disciplined, and vibrant economy with a projected growth of 6.7% for 2005. The total workforce of 397 million has only 7% of workers employed in the organized sector with construction, where asbestos exposure is prevalent, employing 4.4%. The domestic production of asbestos declined from 20,111 tons in 1998-1999 to 14,340 tons in 2002-2003. The imports from Russia and Canada increased from 61,474 tons in 1997-1998 to 97,884 tons in 2001-2002. The production of asbestos cement products went up from 0.68 million tons in 1993-1994 to 1.38 million tons in 2002-2003. The asbestos industry has been delicensed since March 2003. The number of asbestos-based units stood at 32, with the western state of Maharashtra having the largest number. According to official figures, the industry employs 8000 workers. The occupational exposure standard is still 2 fibers/mL, worse still, mesothelioma is not recognized as an occupational disease. The latest cancer registry data have no information on mesothelioma. The health and safety legislation does not cover 93% of workers in the unorganized sector where asbestos exposures are extremely high. Workers remain uninformed and untrained in dealing with asbestos exposure. Enforcement agencies are not fully conscious of the risks of asbestos exposure. Industrial hygiene assessment is seldom carried out and pathologists do not receive training in identifying mesothelioma histopathologically. The lack of political will and powerful influence of the asbestos industry are pushing India toward a disaster of unimaginable proportion.