The "sugar" clear cell tumor of the lung-clinical presentation and diagnostic difficulties of an unusual lung tumor in youth.

A case of the "sugar" clear cell tumor of the lung in a 16-year-old boy is presented. The course of the disease with general symptoms, never reported before, highlights diagnostic difficulties of an extremely rare lung tumor in youth. The boy presented with daily spikes of unexplained high fever of 6 weeks' duration with features of hypochromic microcytic anemia, elevated erythrocyte sedimentation rate, C-reactive protein, alpha(2)- and beta-globulins, and elevated platelet count. The lung tumor was a yellow, circumscribed mass confined to the sixth segment of the left lung. Histological examination revealed the tumor composed of cells with clear cytoplasm with large content of glycogen, with no signs of necrosis, and immunoreactive for HMB-45, but not for cytokeratin, LCA, CD34, and CD68. The performed thoracotomy and segmentectomy were both diagnostic and curative.