Decreasing Albumin mRNA Expression in Cholangiocarcinomas along the Bile Duct Tree.

The progressive technologies in albumin in situ hybridization (ISH) changed the routine application and the differential diagnosis of hepatic malignancies in the last years. The aim of the present work was to assess the diagnostic utility of albumin ISH on different cholangiocarcinoma (CCA) subtypes, as well as to assess how albumin production changes along the biliary tree. Forty-five CCAs were retrospectively selected: 29 intrahepatic (15 small-duct and 14 large-duct subtypes), 7 perihilar, and 9 extrahepatic. Histology was revised in all cases, and albumin ISH was automatically performed by the RNAscope®. ISH was always negative in extrahepatic CCAs, only 1 perihilar case was positive, and any positivity was observed in 25/29 (86.2%) intrahepatic CCAs (p < 0.001). Concerning CCA subtypes, mean cell positivity was 38.8 ± 29.8% in small-duct CCAs and 11.4 ± 21.9 in large-duct CCAs, respectively (p = 0.003); 12/15 (80.0%) small-duct and 3/14 (21.4%) large-duct CCAs showed >5% positive cells (p = 0.002; odds ratio 14.7). The introduction of more sensitive techniques changed the indications for ISH since most small-duct intrahepatic CCAs show diffuse positivity. Albumin positivity decreases from liver periphery to the large ducts, suggesting that ISH can be helpful in the differential diagnosis between small-duct and large-duct CCAs, as well as between intrahepatic large-duct CCAs and metastases.

Albertini E ，Chillotti S ，Monti G ，Malvi D ，Deserti M ，Degiovanni A ，Palloni A ，Tavolari S ，Brandi G ，D'Errico A ，Vasuri F ... -  《-》

A Subset of Intrahepatic Cholangiocarcinomas Express Albumin RNA as Detected by In Situ Hybridization.

Intrahepatic cholangiocarcinomas (ICCs) show morphologic diversity, ranging from tumors composed of nonmucinous small ducts to mucin-producing large duct tumors to tumors with mixed hepatocellular carcinoma features. Diagnosing ICCs can be difficult, especially on biopsy, not only because of the morphologic diversity, but also because metastatic tumors are often in the differential diagnosis. Recently, branched DNA-based albumin RNA in situ hybridization (ISH) has been shown to be a potential sensitive and specific marker for ICC with 99% sensitivity. Using a different RNA ISH technology, we evaluated the expression of albumin RNA ISH in ICC. We performed RNA ISH for albumin using RNAscope on 43 ICCs in a triplicate tissue microarray. Albumin RNA ISH was positive in 18 of 43 (42%) ICCs. Five of the 6 (83%) combined hepatocellular carcinoma-CC were positive in the CC component. None of the tumors with mucin production were positive (0/9). In our cohort, albumin RNA ISH showed a sensitivity of 42% in ICCs, supporting the morphologic diversity of ICCs. Albumin RNA ISH does not appear to be a highly sensitive marker for ICC and hence cannot be used as a stand-alone marker for ICC.

Avadhani V ，Cohen C ，Siddiqui MT ，Krasinskas A ... -  《-》

Pathological survey of precursor lesions in cholangiocarcinoma.

To clarify the pathological significance of two precursors (high-grade biliary intraepithelial neoplasm [BilIN] and intraductal papillary neoplasm of bile duct [IPNB]) in cholangiocarcinomas (CCAs). Ninety-one cases of CCA (47 distal CCAs [dCCAs], 31 perihilar CCAs [pCCAs] and 13 intrahepatic CCAs of large duct type [LD-iCCAs]) were examined for their association with precursors. Neoplastic intraepithelial lesions without underlying infiltrating carcinoma in the surrounding mucosa of CCAs were considered to reflect high-grade BilIN. High-grade BilIN and IPNB were subdivided into gastric, biliary, intestinal and oncocytic subtypes, while CCAs were subdivided into gastrobiliary, intestinal and oncocytic subtypes. The postoperative overall survival (OS) was examined. Fifty-four and 8 of 91 CCAs were associated with high-grade BilIN and IPNB, respectively, while these precursors were unidentifiable in the remaining CCAs. A majority of CCAs were of the gastrobiliary subtype, while the intestinal subtype was occasionally detected, and the oncocytic subtype was rare. CCAs with high-grade BilIN showed a similar postoperative OS to CCAs without precursors, while CCAs with IPNB showed a favorable postoperative OS compared to CCAs without precursors. CCAs were frequently associated with precursors; high-grade BilIN may be a major precursor and IPNB a minor one. CCAs with IPNB showed a favorable postoperative OS compared to CCAs with high-grade BilIN.

Nakanuma Y ，Sugino T ，Kakuda Y ，Nomura Y ，Watanabe H ，Terada T ，Sato Y ，Ohnishi Y ，Fukumura Y ... -  《-》

The Ability to Diagnose Intrahepatic Cholangiocarcinoma Definitively Using Novel Branched DNA-Enhanced Albumin RNA In Situ Hybridization Technology.

Ferrone CR ，Ting DT ，Shahid M ，Konstantinidis IT ，Sabbatino F ，Goyal L ，Rice-Stitt T ，Mubeen A ，Arora K ，Bardeesey N ，Miura J ，Gamblin TC ，Zhu AX ，Borger D ，Lillemoe KD ，Rivera MN ，Deshpande V ... -  《-》

Cholangiolar pattern and albumin in situ hybridisation enable a diagnosis of intrahepatic cholangiocarcinoma.

The histological distinction of intrahepatic cholangiocarcinoma (ICC) from metastatic adenocarcinoma remains a challenge. The primary goal was to evaluate the diagnostic value of morphology and albumin expression in the diagnosis of ICC. We evaluated morphological patterns in 120 ICCs and 677 non-hepatic adenocarcinomas and performed in situ hybridisation (ISH) stain for albumin in the former cohort (retrospective cohort). We also identified 119 samples from primary and metastatic lesions, the validation cohort, in which albumin ISH was performed as part of the diagnostic workup. Targeted sequencing was performed on selected cases. We also mined existing expression profiling data including cases from The Cancer Genome Atlas (TCGA) (41 760 unique samples). In the retrospective cohort, 45% of ICCs and <1% of non-hepatic adenocarcinomas showed a cholangiolar pattern; albumin ISH was positive in 93% of ICCs with significant intratumorous heterogeneity. In the validation cohort, 29% of ICCs showed a cholangiolar pattern and 88% expressed albumin, while all metastatic non-hepatic neoplasms were negative (n=37) (sensitivity 88% and specificity 100%). Targetable genetic alterations (IDH mutations and FGFR2 fusions) were identified in 31% of ICCs (10 of 32). An analysis of the TCGA data validated the specificity of the albumin assay. The cholangiolar pattern and albumin RNA ISH distinguishes ICC from metastatic adenocarcinoma with high specificity. Given the high prevalence of targetable mutations in ICC, albumin RNA ISH is an essential component in the workup of tumours of uncertain origin. A specific diagnosis of ICC could trigger molecular testing and uncover targetable genetic alterations.

Brackett DG ，Neyaz A ，Arora K ，Masia R ，Mattia A ，Zukerberg L ，Misdraji J ，Goyal L ，Zhu AX ，Ferrone CR ，Yilmaz OH ，Deshpande V ... -  《-》