熱帯環境における原発性肝がんの問題  [in Japanese]

We are carrying out studies on the geographical pathology of diseases in tropics and particularly, observing calinical characteristics in the liver diseases under tropical environment. The present paper will be limited to reviewing some of the recent epidemiological studies on liver carcinoma, and current literatures regarding its etiology. Primary carcinoma of the liver has large unexplained geographical variations in incidence. It is several times more common in Africa than in European countries. The highest incidence of primary liver cancer is reported in Bantu males from Lourenco Marques, Mozambique. Our observations in Kenya strongly suggest an increase of liver cancer as other African countries and it appears as one of the common neoplasma among young generation. However, no significant clinical, morphological differences between hepatoma in Kenya and in Japan are found. The pathogenesis of liver cancer in man is still unknown, but several possible precipitating causes have been suggested. Literatures on the role of malnutrition, viral infection, Au-antigen, schistosomiasis, liver cirrhosis and environmental factors as agents responsible for the high incidence of hepatoma are reviewed.