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A4109 - Sleeping Beauty: A Case of a 15-Year-Old Pulmonary Epithelioid Hemangioendothelioma
Author Block: J. Loeb1, U. Chaddha1, W. Elatre2, C. Chang3; 1Pulmonary and Critical Care, University of Southern California, Los Angeles, CA, United States, 2Pathology, University of Southern California, Los Angeles, CA, United States, 3Pulmonary Critical Care and Sleep Medicine, University of Southern California, Keck School of Medicine, Los Angeles, CA, United States.
Introduction: Pulmonary epithelioid hemangioendothelioma (PEH) is a rare low-grade tumor of endothelial cell origin which often presents as a solitary lung nodule. Initially described in 1982 as an “Intravascular Broncho-Alveolar Tumor”, they are often misdiagnosed as benign lesions due to the fact that the size seldom changes over a span of two years. We present a case of PEH which was undiagnosed for 15 years despite multiple pulmonary clinic visits and serial imaging. Case Report: A 74 year-old healthy female presented for a lingular pulmonary nodule that was first discovered incidentally on a self-purchased whole body computed tomography (CT) scan in 2003. At that time, the nodule measured only 3 mm. Because there was no change in size over the course of two years, her pulmonologist reassured her that she did not have cancer and no further followup was necessary. The question resurfaced again in 2015 when she presented to the emergency room with gastroenteritis. A CT scan was performed and incidentally discovered that this nodule was now over 2 cm. She went to see a new pulmonologist who ordered a PET scan and then told her a tissue biopsy was not necessary. Despite her asymptomatic course, the patient worried about the “spots” in her lungs and decided to seek a second opinion at our facility. After review of her old scans, a new PET scan was performed which showed that the lesion had grown to the size of 2.8x2.0 cm (SUV 4.5). In addition, there was a suspicious 1x1.8 cm nodule in the right lower lobe with an (SUV 2.0). A CT-guided biopsy was performed and revealed PEH. The patient was offered dual wedge resections, and is currently considering her options. Discussion: Owing to its extremely low prevalence and indolent growth rate, PEHs are often missed in the differential diagnosis of a solitary pulmonary nodule. It is typically seen as multiple small unilateral or bilateral perivascular nodules which may not always be FDG-avid. Diagnosis is established by immunohistochemical staining for endothelial markers. Because of its rarity, there are no definitive treatment guidelines. However, given its propensity to invade surrounding structures with increasing size over time, surgical resection is typically recommended with a median survival of greater than 10 years. Pulmonologists should be aware of this possible diagnosis, especially as growth occurs outside of the 2-year Fleischner Guideline window.