Introduction <p>Kaposiform haemangioendothelioma (KHE) is a rare, borderline, vascular tumour occurring mostly during childhood. Literature provides reports of KHE in various body regions. To the best of our knowledge, this is the first report of an endonasal KHE. Expert panels recommend systemic pharmacotherapy as first line treatment. In this case, physicians opted for surgical excision of the tumour instead. This report presents therapeutic challenges in this unique case and the succesful course of treatment.</p> Main symptoms/clinical findings <p>The newborn patient presented with saturation drops below 80% SpO₂ while breastfeeding, and recurrent episodes of bloody nasal secretions. Endoscopy showed a large, obstructing and highly vascularized tumour in the right nasal cavity. In imagery, the tumour extended from the olfactory fossa to the nasal floor and eroded the bony border of the medial orbit.</p> Main diagnoses/therapeutic interventions/outcomes <p>In summary of the findings, physicians assumed teratoma or glioma as working diagnosis. During surgery, extensive haemorrhage required the transfusion of approximately 50% of the patient`s total blood volume. Following a satisfactory recovery, the patient was discharged five days after surgery. The patient presented well and tumour free in all follow-up examinations. Histopathological examination confirmed Kaposiform haemangioendothelioma as tumour entity.</p> Conclusion <p>KHE in the upper airway can pose serious life-threats to newborns. Risks associated with diagnostic examination should be weighed up against the accepted level of uncertainty in treatment process decisions. Including caregivers in treatment decisions is recommendable. Despite the absence of KMP, haemorrhage can require transfusion of erythrocyte concentrates. Managing extensive haemorrhage requires preparation, equipment and skill.</p>