Figure 4From: Gastrointestinal metastasis from primary sarcomatoid carcinoma of the lung: a case report and review of the literatureMicroscopic appearance of the colonic lesion. (A) H & E, ×40. (B) Cytokeratin AE1/AE3 (CK AE1/AE3), ×200. (C) Vimentin, ×200. (D) Thyroid transcription factor-1 (TTF-1), ×200. The endoscopic colonic biopsy demonstrates sarcomatoid carcinoma. The carcinoma cells are positive for CK AE1/AE3, Vimentin, and TTF-1.Back to article page