Intravascular papillary endothelial hyperplasia (Masson's tumour) in the jejunum: A case report of unusual gastrointestinal bleeding.

Introduction: Intravascular papillary endothelial hyperplasia (IPEH), originally described by Pierre Masson in 1923, is a benign vascular lesion characterised by the reactive proliferation of endothelial cells. This tumour typically manifests on the fingers, head, neck, or trunk. However, involvement of other organ systems, including abdominal organs, is possible although exceedingly rare. Case presentation: A 57-year-old male patient presented to the emergency department with a 24-h history of recurrent light-headedness. The patient was haemodynamically stable, and physical examination showed no abdominal pain. Digital rectal examination unveiled melena. Initial blood analysis indicated a haemoglobin level of 10.5 g/dL. Comprehensive workup with abdominal computed tomography, upper and lower endoscopy, and gastrointestinal lumen MRI failed to yield significant findings. Discussion: On the fourth day of hospitalisation, persistent melena and transfusion of four units of blood triggered a new upper endoscopy. This endoscopy extended to the jejunum, revealing a submucosal lesion measuring 20 mm, situated approximately 40 cm distal to the ligament of Treitz. Due to ongoing intraluminal bleeding with decreased haemoglobin levels, a segmental jejunal resection was performed. Pathological examination confirmed the diagnosis of a completely resected submucosal IPEH. Conclusion: IPEH, also known as Masson's tumour, is an uncommon vascular lesion within the intestinal tract, occasionally resulting in persistent haemorrhage. The preferred treatment is total surgical resection, with a low likelihood of recurrence. Currently, postoperative surveillance is not recommended. To the best of our knowledge, no cases of recurrence have been documented for Masson's tumour localised in the gastrointestinal tract in the existing literature.