Mutations in genes for perforin-dependent lymphocyte cytotoxicity are associated with haemophagocytic lymphohistiocytosis, a rare disease of severe hyperinflammation that typically becomes evident in early childhood. It has been suggested that individuals with hypomorphic biallelic mutations in genes associated with haemophagocytic lymphohistiocytosis are at increased risk of developing haematological malignancies. We aimed to assess whether relatives of patients with primary haemophagocytic lymphohistiocytosis (ie, heterozygous carriers of these mutated genes) were more likely to develop cancer.
In this retrospective cohort study, we used a multigeneration registry to identify relatives (parents and grandparents) of 79 Swedish children (