What happened, in summary

A 61-year-old woman was admitted in June 2019 with profound fatigue, shortness of breath, severe anaemia, and recurrent gastrointestinal bleeding. Her haemoglobin fell as low as 39 g/L, and she required more than 30 units of red blood cells. Investigations found acquired haemophilia A caused by an inhibitor against factor VIII. Imaging also revealed a 6.1 by 3.7 cm right hilar lung mass, mediastinal lymphadenopathy, bilateral adrenal metastases, and intra-abdominal lymphadenopathy. Biopsy of the left adrenal lesion confirmed extensive-stage small cell lung cancer, with weak synaptophysin staining and a Ki-67 greater than 90%.

The immediate priority was control of bleeding. Prednisone 60 mg daily was combined with recombinant activated factor VII and porcine recombinant factor VIII. The factor VIII inhibitor became undetectable by 12 August, and prednisone was tapered off by mid-September. Once clinically stable, she began carboplatin, etoposide, and atezolizumab. The inhibitor remained suppressed and the bleeding did not recur.

More than a year after presentation, she had completed chemotherapy and remained on maintenance atezolizumab. She also completed thoracic radiation and prophylactic cranial irradiation. The small cell lung cancer remained in remission for a year. She later developed autoimmune myasthenia gravis and received intravenous immunoglobulin. She died after developing aseptic meningitis. Imaging one month before her death still showed stable lung cancer, making the fatal event a treatment-related neurologic complication rather than documented cancer progression.