Paradigmenwechsel in der Beurteilung myeloischer und lymphatischer Neoplasien bei beruflicher Benzolexposition (BK-Ziffer 1303)

Abstract

Benzene-caused hematologic neoplasms may be recognized as an occupational disease (OD) according to the German ordinance on ODs. At present, the OD No. 1303 covers heterogeneous diseases and various chemical agents triggering these diseases. The members of the medical advisory board specializing in ODs within the Ministry of Employment and Social Affairs recently proposed excluding "diseases of the blood, the hematopoietic and lymphatic system caused by benzene" from OD No. 1303 and classifying them as a separate OD. Benzene is generally acknowledged as a cause of acute myeloid leukemia, proven by numerous epidemiologic studies. However, there is less epidemiologic evidence of its association with other hematologic neoplasms, notably non-Hodgkin's lymphoma (NHL). To clarify this issue, the experts evaluated international literature and concluded that all kinds of myeloid and lymphoid malignancies including their prestages can be caused by occupational benzene exposure. Hence, physicians should ask patients about occupational benzene exposure and report any kind of diagnosed hematologic neoplasms, including their prestages, as suspected OD. The advisory board considered that a dose range starting from 10 ppm-years (cumulative benzene exposure) is sufficient for a > 50% probability of causing leukemias according to the WHO classification, including chronic lymphatic leukemia, and the potential preleukemias aplastic anemia and myelodysplastic syndrome, but excluding chronic myeloid leukemia (CML). For NHL and myeloproliferative diseases (including CML) the present epidemiologic evidence is considered not to be sufficient to describe a precise dose-effect relationship.

Epigenetic Effects of Benzene in Hematologic Neoplasms: The Altered Gene Expression

“…As all hematopoietic tumors result from altered stem cells, some authors suggested that different types of myeloid and lymphoid tumors, comprising their pre-stages, can be provoked by occupational exposure to benzene [ 59 ]. Benzene and its metabolites cause harmfulness toward hemopoietic stem cells (HSCs), comprising short- and long-lasting injury to HSCs, and determine negative effects on the BM hematopoietic milieu [ 60 ].…”

Chronic hematologic manifestations of benzene exposure in fuel dispatchers

“…(18) En estudios previos describen que la exposición en dosis superiores a 10 ppm por año, es una cantidad suficiente para desarrollar alguna leucemia, debido a que representa hasta un 50 % de probabilidad de causar trastornos hematológicos, siendo los más comunes la leucemia linfocítica crónica, síndrome mielodisplásico, anemia aplásica, pero excluyendo la leucemia mieloide crónica. (19) Por lo que Hayes et al (20) demostraron que existían mayor riesgo de leucemia mieloide aguda, y otras alteraciones hematológicas tanto benignos como malignos, además de que existía posible riesgo de desarrollar cáncer hematopoyético cuando se encuentran expuestos a niveles por debajo de los ya establecidos (1 ppm). Por otra parte, los despachadores que se encontraban laborando 10 años o más desarrollan linfoma no Hodgkin (RR=4,2), mientras que la exposición continua a 25 ppm o superior se halló el síndrome mielodisplásico y leucemia no linfocítica aguda (RR=7,1).…”

Myelodysplastische Syndrome

“…Dies ist der Fall bei etwa 10 % der MDS-Patienten [5,6]. Eine berufliche Belastung mit organischen Lösungsmitteln, insbesondere Benzol über einen langen Zeitraum, erhöht ebenfalls das Risiko für die Entwicklung eines MDS [7]. Ggf.…”