Paraneoplastic acquired haemophilia A in extensive-stage small cell lung cancer (ES-SCLC) in the era of immunotherapy

Large Cell Neuroendocrine Carcinoma With Acquired Hemophilia A Diagnosed by Endobronchial Biopsy: A Case Report

Primary lung cancer with acquired hemophilia A is rare. We report a case of large cell neuroendocrine carcinoma (LCNEC) with acquired hemophilia A diagnosed by endobronchial biopsy. A 75-year-old male was admitted to our hospital due to severe anemia and multiple organ failure. Hematomas, prolonged activated partial thromboplastin time, decreased activity of factor VIII, and the presence of serum factor VIII inhibitors led to the diagnosis of acquired hemophilia A. Administration of recombinant activated factor VIII and steroid treatment resolved the coagulation abnormalities. Simultaneously, a CT scan showed a lung mass and an endobronchial biopsy confirmed the diagnosis of LCNEC. Although acquired hemophilia A can cause severe bleeding symptoms, a lung cancer diagnosis by bronchoscopy was possible under appropriate treatment of acquired hemophilia A.

Acquired Hemophilia as a Paraneoplastic Syndrome in a Patient With Small Cell Lung Carcinoma

This case report describes a 72-year-old female patient diagnosed with small cell lung carcinoma who was found to have elevated partial thromboplastin time (PTT) after reporting diarrhea and melanotic stool. Further investigations revealed the presence of a factor VIII inhibitor, possibly resulting from a side effect of immunotherapy or of possible paraneoplastic origin. The patient’s PTT remained elevated following a course of steroid treatment, raising the likelihood of paraneoplastic etiology. This case represents a rare paraneoplastic syndrome, with a previously unreported presentation of melanotic stool as opposed to an acute bleeding episode.