Diffuse cirrhosis-like hepatocellular carcinoma: a clinically and radiographically undetected variant mimicking cirrhosis.

A rare variant of hepatocellular carcinoma (HCC) is encountered that produces small cirrhosis-like nodules diffusely throughout the liver (CL-HCC), instead of a larger evident mass. This pattern remains undetected as carcinoma clinically and radiographically and is unexpectedly discovered after liver transplantation in the explanted native liver. We studied 10 such cases (9 males and 1 female, age 35 to 80 y) from 4 medical centers. The pretransplant clinical, laboratory, and radiographical studies were reviewed to determine the cause and stage of liver disease, alpha-fetoprotein (AFP) levels, and detectability of a mass on imaging. All 10 cases had underlying cirrhosis of varying etiology [3 hepatitis C virus (HCV), 3 alcoholic hepatitis, 1 hepatitis B virus, 1 autoimmune, and 2 mixed HCV/alcoholic hepatitis and hemochromatosis/HCV] and underwent orthotopic liver transplantation with no preoperative clinical suspicion of HCC. Ultrasound and/or dynamic imaging showed cirrhosis and no definite HCC. AFP levels were only mildly elevated in only 3 of 10 cases (144, 150, and 252 ng/mL). Grossly, there were innumerable (from about 20 to >1000) small CL-HCC nodules (0.2 to 0.6 cm) scattered among cirrhotic nodules. Histologically, these were well or moderately differentiated HCC, often with pseudoglandular pattern, perinodular sclerotic rims, cholestasis, frequent Mallory bodies, and small vessel invasion. In addition to the usual HCC immunophenotype, CL-HCC showed frequent ubiquitin and cytoplasmic and membranous CD10 positivity, relatively low Ki-67 proliferative index and absence of AFP immunohistochemically. CL-HCC warrants recognition as a unique HCC variant that evades pretransplant detection despite massive tumor burden, mimics cirrhotic nodules, and shows some uncommon pathologic and immunophenotypical characteristics.

Chromosomal changes in fibrolamellar hepatocellular carcinoma detected by array comparative genomic hybridization.

Fibrolamellar hepatocellular carcinoma is a rare subtype of hepatocellular carcinoma with distinct clinical and histological features, and better survival compared with conventional hepatocellular carcinoma in some but not all series. We performed a comparative genomic hybridization analysis on 11 fibrolamellar carcinomas and correlated the findings with clinicopathologic features and survival. Chromosomal imbalances were identified in six cases (55%), whereas the other five (45%) yielded normal results. The mean number of aberrations per case was 3.9 for all cases and 7.2 in abnormal cases. Among the six abnormal cases, gains or losses were observed at 3 loci in two cases, 7 loci in one case, 8 loci in two cases and 14 loci in one case. The most common abnormalities were observed in chromosomes 7, 8 and 18, with 7q gain in five cases and 7p gain in four cases. Aberrations associated with intermediate or advanced conventional hepatocellular carcinomas, including losses at 3q, 4q and 13q were identified in 17-33% of fibrolamellar carcinomas. There was no correlation of chromosomal changes with age, gender and tumor size. The 5-year survival among the six patients with no chromosomal abnormalities was 80% (4/5) compared with 33% (2/6) in patients with chromosomal abnormalities (P=0.1). In conclusion, fibrolamellar carcinomas show fewer chromosomal abnormalities compared with those reported in literature for conventional hepatocellular carcinoma. The most common abnormalities occur in chromosomes 7 and 8. Fibrolamellar carcinomas with chromosomal changes appear to behave more aggressively compared with cases with no cytogenetic abnormalities. The favorable outcome in some fibrolamellar carcinomas may be due to absent or low number of cytogenetic aberrations.

TNF-alpha-mediated apoptosis in vascular smooth muscle cells requires p73.

Atherosclerosis, now considered an inflammatory process, is the leading cause of death in the Western world and is manifested by a variety of diseases in multiple organ systems. Because of its prevalence and associated morbidity, novel therapies directed at arresting this progressive process are urgently needed. The inflammatory mediator TNF-alpha, which is known to contribute to apoptosis in vascular smooth muscle cells, has been shown to be intimately involved in the atherosclerotic process, being present at elevated levels in human atheroma as well as possibly being responsible for plaque rupture, a clinically devastating event. In light of our earlier finding that p73 is a proapoptotic protein in vascular smooth muscle cells, which are involved in plaque progression as well as rupture, we asked whether TNF-alpha mediates apoptosis in these cells through p73. We now show that p73 is present in spindle-shaped cells within human atheroma, and p73beta, an isoform that is pivotal in both apoptosis and growth suppression, is induced in vascular smooth muscle cells in vitro by serum but not by PDGF-BB. In addition, TNF-alpha, when added to these cells in the presence of serum-containing media, increases p73beta expression and causes apoptosis in both rat and human vascular smooth muscle cells. Inhibition of p73 activity with a dominant inhibitory NH2-terminally deleted p73 plasmid results in markedly decreased TNF-alpha-induced apoptosis. Thus p73beta is likely a mediator of the apoptotic effect of TNF-alpha in the vasculature, such that future targeting of the p73 isoforms may ultimately prove useful in novel atherosclerosis therapies.