Sinonasal hemangiosarcoma following juvenile occupational exposure to formaldehyde when breeding farm animals

Hemangiosarcomas are heterogeneous malignancies possibly originating in any part of the body, rare in humans. The web of causation of human hemangiosarcomas remains poorly understood, to date, except for subsets of cases which have been recognized in a well-defined causal correlation to vinyl chloride or to ionizing radiation. In 2005, the International Agency for Research on Cancer ranked formaldehyde as a human carcinogen, causally related to both nasopharyngeal cancers and acute non-lymphocytic leukemias; at the time, the evidence in favor of a causal relationship of formaldehyde to sinonasal cancers was stated as "limited". In 2024, an umbrella review reported a significantly increased risk for sinonasal cancers among formaldehyde-exposed workers.

A sinonasal hemangiosarcoma affecting an Italian male born in 1957, diagnosed in 2022, was reported to the Italian National Registry of Sino-Nasal Cancers (ReNaTuNS); the patient's occupational history revealed a remote exposure to formaldehyde, used as a disinfectant, when breeding farm animals, from 1967 to 1976. No previous reporting has been found about a possible association between formaldehyde and sinonasal non-epithelial cancers.

Formaldehyde is, in our opinion, a suitable candidate to be considered for playing a causal role in the causation of the neoplasm; formal studies are required to test the hypothesis.