Two Surgical Cases of Solitary Squamous Cell and Glandular Cell Mixed Papilloma of the Lungs

━━ Background. Solitary squamous cell and glandular mixed papilloma (mixed papilloma) is a histological subtype of papilloma, a rare, benign pulmonary epithelial tumor reported to undergo occasional malignant transformation. We herein present two surgical cases of mixed papilloma. Case Presentation. Case 1: A 49-year-old male was found to have a 28-mm nodule in right S8 with pleural indentation and spicule formation on chest CT. FDG-PET indicated accumulation with SUV 14.8, and the serum CEA level was 5.2 ng ml. The preoperative pathological diagnosis was well differentiated squamous cell carcinoma based on the findings of a bronchoscopic biopsy. Right lower lobectomy and lymph node dissection were performed. The postoperative pathological examination revealed features of mixed papilloma. Case 2: A 72-year-old male presented with obstructive pneumonia. A bronchoscopic examination disclosed a polypoid tumor obstructing the B6 bronchus, and squamous cell carcinoma was detected in a biopsy specimen. The serum SCC level was 1.6 ng ml. Left S6 segmentectomy with B6 wedge resection and lymph node dissection was performed. The postoperative pathological examination revealed mixed papilloma with stage 0 squamous cell carcinoma protruding into the internal lumen of the B6 bronchus. (JJLC. 2013;53:856-862)