Immunohistochemical Classification of Hepatic Adenomas and Atypical Hepatocellular Neoplasms: Correlation with Clinicopathologic Characteristics and Chromosomal Abnormalities
K Evason, J Grenert, L Ferrell, S Kakar. UCSF, San Francisco, CA
Background: The distinction of hepatic adenomas(HA)from hepatocellular carcinoma(HCC)is difficult in males,elderly women,or when focal atypical features are present.These tumors can show chromosomal abnormalities(Chr Abn)typical of HCC and can recur or metastasize.Recently,HAs have been classified based on inflammatory features and β-catenin(βC)pathway abnormalities.The latter may have higher risk for progression to HCC.We examine the relationship of SAA expression and βC abnormalities with clinicopathologic features and Chr Abn.
Design: Immunohistochemistry for βC,glutamine synthetase(GS)and serum amyloid associated protein(SAA)was done in 23 HA,36 AHN and 18 well-differentiated HCC.AHN was used for HA-like tumors in men,women >50 or <15 years and/or with focal atypia(small cell change,pseudoglands,thick plates).Tumors with nuclear βC and/or diffuse GS were regarded as βC abnormal.Chromosomal gains/losses had previously been determined in 39 cases using CGH or FISH.
Results: βC and Chr Abn in AHNs were more common than HA,but were similar to HCC(table1).HAs and AHNs with abnormal βC were associated with atypical morphology(table2).Follow-up data was limited but adverse outcome was observed in 3 tumors with abnormal βC(2 recurrences,1 metastasis);in addition,transition to areas of HCC was observed in 2 cases.Chr Abn were more often seen in tumors with abnormal βC(89%vs12%,p<0.001).
|Inflammation||Telangiectasia||βC abnormal||SAA +||Chr Abn|
|Atypical age/sex||Atypical morphology||Inflammation||Telangiectasia||Chr Abn|
|βcatenin abn vs normal||43 vs 30||71 vs 20||35 vs 44||35 vs 38||89 vs 12|
|SAA positive vs negative||43 vs 22||33 vs 42||48 vs 26||45 vs 21||50 vs 38|