[The basic causes of errors in the cytological diagnosis of lung and esophageal cancers]

The causes of errors in cytological diagnosis in 615 patients with carcinoma and benign lesions of the lung and in 847 patients with those of oesophagus are studied and systematized. Percentage of errors was 15.93 for the lung diseases and 4.48 for diseases of the oesophagus. The error causes are subdivided into objective and subjective ones.