Hepatocellular carcinoma with spontaneous regression of multiple lung metastases

Spontaneously regressed lung metastasis of hepatocellular carcinoma (HCC) i n a 82-year-old Japanese man with liver cirrhosis:was recorded. Multiple no dular lesions of both lungs, up to 1 cm across, were shown on chest X-ray w hen the clinical diagnosis of HCC was made because of the presence of a liv er mass on abdominal computed tomography (CT) scan and high serum a-fetopro tein (AFP) value, The lung lesions which were regarded clinically as metast asis of HCC decreased in number and size 7 months later, and subsequenly di sappeared a further 7 months radiographically, However, the liver mass reve aled no reduction on abdominal CT, despite normalization of the serum AFP v alue, and the patient died 7 months after the disappearance of the lung les ions, The,patient refused biopsy for the liver mass and anticancerous treat ment during the course of the disease. At autopsy, the liver mass, 13 cm in diameter, histologically featured moderately differentiated HCC. Only one metastasis, 0.5 cm across, was obvious in the left lower lung lobe, In addi tion, there were 14 minute lesions in both lungs, up to 0.2 cm across, incl uding three with complete necrosis and 11 with histocytic reaction and fibr osis. The necrotic tissue was filled with large ghostly cells that appeared to be debris from a neoplastic tissue, regardless of no viable tumor cells among them. The clinical and autopsy findings highly suggested that the pa tient developed spontaneous regression of multiple lung metastases of HCC a nd subsequently left the very small lesions as the vestige. Thus, the histo logy of these lesions may exhibit a process of the regression as the sequen ce of events, i.e., a transition from necrosis of the metastatic HCC to its fibrosis, Presence of an effective factor(s) in relation to the regression was unclarified. There has been no reported cases with regression of the o nly metastasis of HCC in the literature to date.