Asbestos-related cancers in Brazil.

Since Brazil is a major producer, consumer and exporter of asbestos, monitoring the occurrence of asbestos-related diseases is crucial. Whereas other asbestos-related cancers are multifactorial in origin, the major risk factor for mesothelioma is asbestos. In many countries, the occurrence of this malignancy in the population reflects the use of asbestos in the economy. In Brazil, nevertheless, data on mesothelioma are limited and their quality has not been verified. Mortality from mesothelioma (C45 in the 10th revision of the International Classification of Diseases – ICD-10) and from pleural cancer (C38.4) in 1980-2010 has been described 1 but incidence data provided by Brazilian Population Based Cancer Registries (PBCR) have received little attention. Data from the PBCR are collected in a public domain databank: SisBasepop 2. Six of them exhibited adequate quality criteria for inclusion in the latest update 3 of Cancer Incidence in 5 Continents (CI5). These cover residents in the cities of Aracaju, Belo Horizonte, Cuiabá, Fortaleza, Goiania and São Paulo, with an overall population of 17.9 million (less than 10% of the total population of the country). According to CI5, in 2003-2007, the pool of these registries collected a total of 82 cases of mesothelioma (51 men and 31 women) and 59 cases of cancer of the pleura not specified as mesotheliomas (35 men and 24 women). Around 75% of cases were collected by the São Paulo city PBCR, the largest in the country. For both mesotheliomas and other pleural cancers, all annual rates (age-standardized on the world population; ASR) are less than 2 per million inhabitants. For the sake of comparison, corresponding rates for mesothelioma in the pool of Italian Cancer Registries were 18.4 in men and 5.1 in women, whereas rates for pleural cancer were respectively 2.3 and 0.9 (Crocetti E. Letter to Benedetto Terracini, 03/Feb/2015). In Brazilian registries, 89% of mesotheliomas and 80% of pleural cancers were histologically confirmed, and 11% and 7% were Death Certificates (DC) only 3. Histologically verified cases in Italy were 97% and 35 % while DC only were 0.1% and 8% (Crocetti E. Letter to Benedetto Terracini, 03/ Feb/2015). Thus, the available data provide some information on the probability for a registered case to be a “false positive”. The sensitivity of Brazilian cancer registries in the detection of mesothelioma cases (i.e. the complementary to “false negatives”) is more difficult to estimate. C38.4 cancers are problematic. A French study has estimated that 86% of “pleural cancers” were in fact mesothelioma 4. Similar findings were obtained from a study in the UK 5. It is reasonable to believe that this also happens in Brazil. International comparisons on the burden of asbestos-induced cancer have considered jointly C38-4 and C45 6. In-