Liver-Cell Adenoma

Abstract

Liver-cell and bile-duct-cell adenomas are rare, and to our knowledge no description has previously been published of the angiographic findings in a microscopically proved liver-cell adenoma. A 22-year-old Caucasian housewife entered the University of California Medical Center, San Francisco, on Feb. 21, 1966, for evaluation of mild asymptomalic hypertension. Her past history was not remarkable except for a weight gain of 15 lb. during the preceding four months. On physical examination, this healthv-appearing young woman was in no distress. The positive findings included an enlarged liver and a blood pressure of 170/100 mm Hg. Laboratory studies revealed no abnormalities. Renal arteriography showed the renal arteries to be normal, but the hepatic arteriogram was abnormal. At least three separate masses were identified with in the liver (Figs. 1–3). The scintiscan is shown in Figure 4. At laparotomy, the liver was found to be enlarged by at least 4 distinct masses, rather than the 3 shown angiographically. The largest occupied the anterior right lobe, and at least 2 others were felt within the posterior right lobe. The left lobe was nearly replaced by a large neoplasm that arose under the falciform ligament. The liver tissue surrounding the hepatic masses appeared normal, as did the extrahepatic biliary system. Spider-like vascular channels were lying over the surfaces of the tumors, and the tumors themselves protruded from the normal liver in such a manner that the surrounding liver tissue was compressed. The frozen-section histologic diagnosis of a biopsy specimen of the largest tumor was liver-cell adenoma. Bilaterality of the tumors made total removal impractical. An uneventful excisional biopsy of the largest of the right liver lobe tumors was made. Gross examination of the resected specimen showed an encapsulated mass measuring 8 cm in diameter. The thin capsule contained numerous thin-walled vessels (Fig. 1). A 3 mm peripheral zone of brownish-yellow tissue lay beneath the capsule, and central to this subcapsular zone the liver parenchyma showed small foci of hemorrhage and rare widely spaced areas of scarring. Microscopic examination of the specimen disclosed a well formed capsule. A small zone of compressed liver tissue was encountered beneath the capsule, with occasional bile plugs. Vacuolation of the cytoplasm in this area was caused primarily by glycogen as shown by special stains. A few zones intermediate between the compressed subcapsular liver tissue and the liver-cell adenoma were suggestive of distorted portal areas with small bile ductules, veins, and possibly arterioles. The liver-cell adenoma itself (Fig. 5) was composed of sheets of liver cells without portal triads or central veins. Deep within the adenoma were numerous thin-walled venous structures (Figs. 2 and 3).