A report of resected mesenchymal hamartoma of the liver in adult

A 47-year-old woman was coincidentally diagnosed to have a liver tumor by ultrasonography. Of tumor markers, only CA19-9 was positive. Imaging studies showed the 7 cm-sized tumor located in the segment 6 of the liver, and the homogenious stain. And the tumor had a component of cystic and solid parts. We carried out the resection of segment 6. The tumor with the well-defined margin was 7.5cm×7.5cm in diameter and included large and small cysts. By the histopathological examination, the tumor, which was mainly consisted of fibrous connective tissue with the various sized blood vessels, lymph vessels and small bile ducts. Now she has been well and there is no reccurence at three years after surgery. There were 64 reported cases in Japan, which included 52 infants and 12 adults. Tumor growth rate in infants is rapid while it is slow adults. It is generally difficult to distinguish mesenchymal hamartoma from malignant tumor by imagings. Therefore, in both infants and adults, resection can be the first option of therapy. Although this tumor is not malignant, 3 recurred cases have been reported. We should be careful about the follow-up.