Pulmonary Epithelioid Hemangioendothelioma: A Rare and Diagnostically Challenging Tumor in a Young Age

Pulmonary epithelioid hemangioendothelioma (PEH) is a rare and unpredictable vascular tumor of the lung, often presenting with an uncertain prognosis. While it is generally considered to exhibit borderline malignancy, it can sometimes progress aggressively. Diagnosing PEH can be particularly difficult both clinically and histopathologically, as it often mimics a variety of neoplastic and inflammatory conditions, leading to delayed recognition and treatment. An increased level of clinical suspicion is essential for accurate diagnosis. We report a 23-year-old male initially misdiagnosed with empyema and tuberculosis, who presented with progressive respiratory symptoms. Imaging revealed bilateral pulmonary nodules and right lower lobe collapse. Diagnosis was confirmed through transbronchial cryobiopsy and immunohistochemistry, showing tumor cell positivity for CD31, CD34, and ERG. Despite treatment with cyclophosphamide and sorafenib, the patient's condition deteriorated rapidly, resulting in death. This case emphasizes the rarity and diagnostic challenges of PEH. A multidisciplinary approach combining histological evaluation and immunohistochemical testing is crucial for establishing the correct diagnosis.