[Differential diagnosis problems in the assessment of pulmonary coin lesions].

Cause for the publication was a primary hepatocellular carcinoma, the clarification of which was performed on an unusual diagnostic way. The consequence of a circular focus near the pleura were differential-diagnostic considerations. By an aimed biopsy and thoracoscopy a malignant tumour could be ascertained, in which case the histologic investigation resulted in the solitary metastasis of a hepatocellular carcinoma. The authors enter the problems of the diagnosis of pulmonary circular foci and of the hepatocellular carcinoma.