Carcinomas of the Upper Respiratory Tract which were Difficult to Discriminate from Roentgenographically Occult Lung Cancer.

In sputum-positive cases, it is important to discriminate radiographically occult lung cancer from carcinoma of the upper respiratory tract. In this article, two cases of early carcinoma of the upper respiratory tract detected by sputum cytology in a mass screening are reported. A method of detecting the location of cancer in patients with positive sputum cytology who have neither abnormal chest x-ray findings nor abnormal broncho-scopic findings is discussed. Case 1 was a 65-year-old man with positive sputum cytology examined by chest x-ray, chest CT, bronchofiberscopy, nose x-ray, nose CT, and laryngofiberscopy. None of the examinations revealed abnormal findings. However, in a random biopsy of the epipharynx, squamous cell carcinoma was found. Case 2 was a 64-year-old man with positive sputum cytology examined by almost the same methods as in case 1. Mucosal thickness was detected in the left maxillary sinus by nose CT. Aspiration cytology of the left maxillary sinus revealed squamous cell carcinoma. Early stage carcinomas of the epipharynx and maxillary sinus are very difficult to diagnose. It was concluded that nose CT and biopsy of the epipharynx should be performed in cases with positive sputum cytology who have neither abnormal chest x-ray findings nor abnormal bronchoscopic findings.