Postoperative paraneoplastic factor VIII auto-antibodies in patients with solid tumours

Paraneoplastic FVIII antibodies may occur concurrent with the diagnosis or at various times after diagnosis and treatment of cancer. Between 2002 and 2009, we observed two patients with acquired haemophilia A due to an FVIII auto-antibody, which appeared 4 and 5 months after uncomplicated cancer surgery. We aimed to evaluate if such an association of cancer surgery and FVIII antibody formation has been observed previously. We retrieved all published case reports of cancer-associated FVIII auto-antibodies from PubMed for the period 1950-2010. The search in the literature revealed 13 patients in whom a FVIII inhibitor developed after uncomplicated surgery for cancer and a bleeding-free time interval of up to 6 months; 11/15 patients had abdominal cancers (five colon cancer, four pancreatic cancer, gastric cancer and choledochus carcinoma one each). The median time period between surgery and antibody detection was 3 months (1 week-6 months). In most cases, the antibody titre was low (median: 14 BU mL⁻¹, range: 1.7-64 BU mL⁻¹). Immunosuppressive treatment was successful in most of the cases - nine of the treated patients reached a sustained CR of the antibody after a median time of 3 months. Postoperative paraneoplastic FVIII inhibitors may be regarded as a special, not yet recognized subgroup of acquired FVIII antibodies. They share some characteristics with postpartum FVIII inhibitors with regard to the latency period between the triggering event and the appearance of the antibody, and between the usually low antibody titres and their good response to immunosuppressive treatment.