Original ArticlesHemangioblastoma-like Clear Cell Stromal Tumor of the Lung A Clinicopathologic and Immunohistochemical Study of 5 CasesLindholm, Kaleigh E. MD*; Moran, Cesar A. MD†Author Information *Department of Pathology, The University of Colorado, Aurora, CO †Department of Pathology, The University of Texas, MD Anderson Cancer Center, Houston, TX Conflicts of Interest and Source of Funding: The authors have disclosed that they have no significant relationships with, or financial interest in, any commercial companies pertaining to this article. Correspondence: Cesar A. Moran, MD, Department of Pathology, MD Anderson Cancer Center, 1515 Holcombe Boulevard Houston, TX 77030 (e-mail: [email protected]). The American Journal of Surgical Pathology: June 2020 - Volume 44 - Issue 6 - p 771-775 doi: 10.1097/PAS.0000000000001429 Buy Metrics Abstract Five cases of an unusual primary benign stromal tumor designated as hemangioblastoma-like clear cell stromal tumor of the lung are presented. The patients are 4 women and 1 man between the ages of 39 and 52 years of age (average: 45.5 y). The patients presented with nonspecific symptoms of cough, chest pain, or dyspnea. None of the patients had any prior history of malignancy or tumor elsewhere. Diagnostic imaging showed the presence of an intrapulmonary tumor. Lobectomy was performed in all 5 patients. Grossly, the tumors were well-demarcated but not encapsulated with focal areas of hemorrhage without necrosis. Histologically, low power examination showed a cellular proliferation alternating with discrete dilated vessels reminiscent of a vascular neoplasm. Higher magnification showed medium-sized cells with clear cytoplasm arranged in sheets and cords. Mitotic activity and marked cellular atypia were not present. A wide panel of immunohistochemical studies was performed including epithelial, neural, muscle, vascular, and neuroendocrine markers, all of which showed negative staining. Tumor cells showed positive staining for vimentin. In 2 cases, fluorescence in situ hybridization for the solitary fibrous tumor was performed and was negative. Clinical follow-up in 3 patients showed no evidence of recurrence. The cases herein presented highlight an unusual benign stromal tumor of the lung, which needs to be considered in the differential diagnosis of tumors with a clear cell and vascular appearance. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.