Intravascular Papillary Endothelial Hyperplasia of the Chest Wall Misdiagnosed as a Malignancy on Fine Needle Aspiration
A 75-year-old male underwent a subtotal gastrectomy at 62 years of age. He was diagnosed as a well-differentiated adenocarcinoma confined to the gastric mucosa. He remained in good health until 3 years ago, at which time he noticed a 2 cm asymptomatic mass on the chest wall. The mass was situated 10 cm apart from the previous surgical scar. One week before hospital admission, he experienced pain at the site of the mass and was referred for further evaluation.\nThe clinical condition of the patient was good. Physical examination revealed a firm, smooth, round mass on the anterior chest wall. The size of the mass had not changed since initial presentation. The mass was initially presumed to be a lipoma or epidermal inclusion cyst on physical palpation. However FNA was necessary to rule out a metastatic adenocarcinoma originating from the stomach.\nThe FNA cytology showed low cellular smears containing a few cohesive sheets of polygonal pleomorphic cells with vesicular chromatin, prominent nucleoli, abundant dense cytoplasm, and cytoplasmic vacuoles. Scattered individual polygonal cells were also present in a hemorrhagic background (). Some fibrins were intermingled, and some of the cells showed long cytoplasmic processes suggestive of spindling. Pleomorphic polygonal cells were arranged in alveolar or glandular patterns that were suspected to be metastatic adenocarcinoma.\nThe pathologic findings of the excised mass showed a well-demarcated vascular lesion within the skeletal muscle associated with a hematoma. There was an anastomosing papillary core lined by plump endothelial cells. The papillae contained fibrin-like materials and the endothelial cells were pleomorphic with vesicular nuclei and prominent nucleoli (). Mitotic figures were not observed. The overall cellular features were similar to those observed in the aspirate smears. The cells showed diffuse strong cytoplasmic immunoreactivity for CD34 and factor VIII-related antigen, and were negative for cytokeratin, confirming the diagnosis of intravascular papillary endothelial hyperplasia.