Fukuo Kondo

Pathologic diagnosis of early hepatocellular carcinoma : a report of the international consensus group for hepatocellular neoplasia

Advances in imaging techniques and establishment of surveillance protocols for high-risk populations have led to the detection of small hepatic nodules in patients with chronic liver diseases, particularly those with cirrhosis or chronic hepatitis caused by hepatitis B or C viruses. These nodules, comprising a broad range of diagnostic entities—some benign and some with malignant potential—are currently defined histologically, and their clinical management often depends on the ability to make a reliable histologic diagnosis. Evidence accumulated in the last two decades strongly favors the existence of a sequence of events in hepatic nodules that precedes the emergence of hepatocellular carcinoma (HCC),1-10 and these lesions are recognized as precursors of HCC. However, from the beginning of their recognition, there has been considerable confusion concerning nomenclature and diagnostic approaches to these hepatic nodules. To clarify these issues, an International Working Party (IWP) of the World Congresses of Gastroenterology proposed a consensus nomenclature and diagnostic criteria for hepatocellular nodular lesions in 1995.11 The IWP classified nodular lesions found in chronic liver disease into large regenerative nodule, lowgrade dysplastic nodule (L-DN), high-grade dysplastic nodule (H-DN), and HCC; this nomenclature has been widely adopted. In addition, the IWP introduced the concept of dysplastic focus as a cluster of hepatocytes with features of early neoplasia (in particular small cell change or iron-free foci in a siderotic background) measuring less than 0.1 cm, and defined small HCC as a tumor measuring less than 2 cm. More recent studies support the division of small HCC into two clinico-pathological groups that have been termed early HCC and progressed HCC. Early HCC has a vaguely nodular appearance and is well differentiated. Progressed HCC has a distinctly nodular pattern and is mostly moderately differentiated, often with evidence of microvascular invasion.12 Early HCC has a longer time to recurrence and a higher 5-year survival rate compared with progressed HCC.13 Small lesions with malignant potential have only subtle differences from the surrounding parenchyma, making them difficult to assess reproducibly. Differences in the application of diagnostic criteria between Western and Eastern pathologists has been a persistent difficulty in research and clinical management of these lesions.14 In order to obtain a refined and up-to-date international consensus on the histopathologic diagnosis of nodular lesions, such as dysplastic nodules and early HCC, the International Consensus Group for Hepatocellular Neoplasia (ICGHN) was convened in April 2002 in Kurume, Japan. The group has met several times up to July 2007 under the auspices of the Laennec Liver Pathology Society. The ICGHN is currently comprised of 34 pathologists and two clinicians from 13 countries. It includes most members of the original IWP who are still active and all the participants from the first ICGHN meeting. This consensus document summarizes the results of our meetings.

Percutaneous ethanol injection for the treatment of small hepatocellular carcinoma : study of 95 patients

Abstract Percutaneous ethanol injection (PEI) was applied to 120 lesions in 95 patients with hepatocellular carcinomas (HCC) smaller than 3 cm in the past 6 years. All main target tumours, in 67 patients who had been followed by sonography for more than 6 months after PEI, decreased in size; 28 tumours (41.8%) became undetectable and have remained so until now. The 1‐, 2‐, 3‐, 4‐ and 5‐year survival rates calculated by the Kaplan‐Meier method were 93%, 81%, 65%, 52% and 28% respectively. These survival rates were better than those of patients with HCC smaller than 3 cm who did not receive anticancer treatment (P <0.01). The survival of patients of the Childs A or Childs B status was better than that of those with Childs C disease. Recurrence occurred in areas within the liver different from the original lesion in 34% in one year, 61% in two years and 66% in three years after PEI. PEI was then repeated in 61% of such patients.

Benign nodular hepatocellular lesions caused by abnormal hepatic circulation: etiological analysis and introduction of a new concept.

Abstract Problems in definitive diagnosis and etiology of various benign nodular hepatocellular lesions were evaluated. Of these lesions, focal nodular hyperplasia (FNH), nodular regenerative hyperplasia (NRH), nodular lesions associated with idiopathic portal hypertension (IPH), non‐cirrhotic large regenerative nodules (LRN), hepatocellular adenoma (HA)‐like hyperplastic nodules, and partial nodular transformation (PNT) have been suggested to be related to abnormal hepatic circulation. However, the following points are considered to need further clarification: (i) is the abnormal circulation caused by thrombosis, vasculitis, or congenital anomaly?; (ii) is thrombosis a cause or a result of congestion?; (iii) are impaired blood vessels primarily the portal veins or arteries?; (iv) how are these disorders related to various syndromes, immunological abnormalities and abnormal blood flow of other organs, which are reported to coexist with these lesions often?; and (v) how should non‐typical cases, which differ from typical cases, be interpreted? In addition, a concept that may lead to solving these problems (anomalous portal tract syndrome; a hypothesis that congenital vascular anomaly is the origin of these benign nodular hepatocellular lesions) was introduced.

Ductular reaction is helpful in defining early stromal invasion, small hepatocellular carcinomas, and dysplastic nodules.

Stromal invasion is 1 of the main features used to distinguish high‐grade dysplastic nodules (DNs) from well‐differentiated hepatocellular carcinomas (HCCs). The authors hypothesized that ductular reaction (DR) takes place around noninvasive hepatocellular nodules but not within the stroma contiguous to invasive HCC.

Application of a new histological staging and grading system for primary biliary cirrhosis to liver biopsy specimens: Interobserver agreement

Recently the authors proposed a new staging and grading system for primary biliary cirrhosis (PBC) that takes into account necroinflammatory activity and histological heterogeneity. Herein is proposed a convenient version of this system. Scores for fibrosis, bile duct loss, and chronic cholestasis were combined for staging: stage 1, total score of 0; stage 2, score 1–3; stage 3, score 4–6; and stage 4, score 7–9. Cholangitis activity (CA) and hepatitis activity (HA) were graded as CA0–3, and HA0–3, respectively. Analysis of interobserver agreement was then conducted. Digital images of 62 needle liver biopsy specimens of PBC were recorded as virtual slides on DVDs that were sent to 28 pathologists, including five located overseas. All participants were able to apply this version in all 62 cases. For staging, kappa was 0.385 (fair agreement) and the concordance rate was 63.9%. For necroinflammatory activity, the kappa and concordance rate were 0.110 (slight agreement) and 36.9% for CA, and 0.197 (slight agreement) and 47% for HA, respectively. In conclusion, this new staging and grading system for PBC seems to be more convenient and practical than those used at present, but more instruction and guidance are recommended for the grading of necroinflammatory activity in practice.

Proposal of histological criteria for intraepithelial atypical/proliferative biliary epithelial lesions of the bile duct in hepatolithiasis with respect to cholangiocarcinoma: Preliminary report based on interobserver agreement

Biliary lining epithelia of the bile ducts in biliary diseases are known to have intraepithelial atypical/proliferative lesions related to the development of cholangiocarcinoma. The purpose of the present study was to determine the histological criteria for these lesions based on interobserver agreement. Digital images of 30 intraepithelial atypical/proliferative lesions in the stone‐containing intrahepatic bile ducts of hepatolithiasis (30 cases) were sent to 10 pathologists. At first, 10 pathologists made a diagnosis (either of reactive/regenerative change, low‐grade or high‐grade biliary intraepithelial neoplasia (BilIN‐1 and BilIN‐2), or in situ carcinoma (BilIN‐3)) based on their own criteria. The histological criteria for these four lesions were then determined, and the digital images of the same lesions with proposed criteria were re‐distributed. Interobserver agreement on these four lesions was slightly improved (κ = 0.44, first diagnosis; 0.49, second diagnosis) and intraobserver agreement was ‘almost perfect’ (κ = 0.82 at both first and second diagnosis). Interobserver agreement between BilIN‐1 and BilIN‐2 and that between BilIN‐2 and BilIN‐3 were ‘moderate’, although the agreement between regenerative/reactive change and BilIN‐1 was ‘fair’. In this report, we propose histological criteria for reactive/regenerative change, BilIN‐1, BilIN‐2 and BilIN‐3. Improvement of interobserver agreement suggests their applicability in diagnostic and research fields.

Relationship between copper, zinc and metallothionein in hepatocellular carcinoma and its surrounding liver parenchyma

BACKGROUND/AIM Accumulation of copper (Cu) in hepatocellular carcinoma (HCC), especially in small tumors, is greater than that in the surrounding liver parenchyma. Metallothionein (MT) is considered to be present as Cu-MT, Zn,Cu-MT or Zn-MT. The aim of this study was to determine the presence and localization of Cu-MT and Zn-MT in HCC and surrounding liver parenchyma. METHODS In 16 HCC patients, surgically resected specimens including HCC and surrounding liver parenchyma were evaluated. RESULTS The level of Cu present in small HCC (<4 cm in diameter) was significantly greater than that in the surrounding liver parenchyma (p<0.05). However, the level of Cu in large HCC (>4 cm in diameter) was similar to that in the surrounding liver parenchyma. Analysis by Sephadex G-75 gel filtration revealed that the peak fraction due to Cu was identical to that due to MT in 14 (87.5%) of 16 HCC, the peak fraction due to Cu and Zn was identical to that due to MT in 2 (12.5%) HCC, and the peak fraction due to Zn was identical to that of MT in none of 16 HCC. CONCLUSIONS Accumulation of Cu in small HCC, in which Cu was present as Cu-MT or Zn, Cu-MT, was greater than that in the surrounding liver parenchyma. Cu accumulation and the presence of MT in the liver may be related to carcinogenesis of HCC, because of the similarity of these findings in the experimental data of Long-Evans rats with a cinnamon-like coat color who develop HCC spontaneously.

Morphological clues for the diagnosis of small hepatocellular carcinomas

Histological features of 44 cases of small hepatocellular carcinoma (HCC) were examined and compared with those of large regenerative nodules. The highly differentiated type of HCC most often occurred in nodules which were less than 2 cm in diameter. Noticeably, in 9 out of 15 such cases (60.0%), tumour cells were arranged in trabeculae of almost normal thickness (normotrabecular pattern). These trabeculae, however, showed variable nuclear crowding, occasional microacinar formation, and increase in cytoplasmic basophilia. It is emphasized that the presence of this triad may be a very reliable indicator for the histological identification of early HCC, especially in examining limited material such as a biopsy specimen. However, cellular and structural atypia becomes more prominent in nodules which are larger than 2 cm.

Etiological analysis of focal nodular hyperplasia of the liver, with emphasis on similar abnormal vasculatures to nodular regenerative hyperplasia and idiopathic portal hypertension.

Pathological studies were performed on 23 cases of focal nodular hyperplasia (FNH) under the hypothesis that FNH is a hyperplastic lesion caused by abnormal vasculatures of portal tracts within the nodule. For a comparison of the histological features of portal tracts, nodular regenerative hyperplasia (NRH), idiopathic portal hypertension (IPH), chronic hepatitis and so-called normal liver were used as control tissues. Extranodular areas of FNH nodules were also examined. Clinical data were briefly summarized. Most of the portal tracts within FNH nodules showed various abnormal findings, such as dilatation and/or stenosis of portal vein, muscular thickening of arterial wall with dilated or stenotic lumina, lymphocyte infiltration, and bile ductule proliferation. However, portal vein thrombi were not found. These findings were not thought to represent compensatory reaction to portal vein thrombosis. Similar abnormal features were also observed in extranodular areas of FNH although to a milder degree. These abnormal features resembled those of NRH and IPH. Moreover, the characteristic scar-like tissues within FNH nodules were proved to be abnormally large portal tracts including large feeding arteries, portal veins and bile ducts. It has been believed that septa and scar-like tissue within FNH nodules are not portal tracts and that arterial malformation independent of portal tracts are related to the development of FNH. In addition, venous structures within FNH modules have until now not been considered to be portal veins. However, this study revealed that severe anomaly of portal tracts including portal veins and hepatic arterial branches existed in FNH nodules. Moreover, portal tracts in extranodular areas were also abnormal. Clinically, only one patient had a history of oral contraceptives. Based on these findings, congenital anomaly of the portal tracts histologically resembling the abnormal portal tracts of NRH and IPH may be related to the pathogenesis of FNH.

Accumulation of copper in the liver and hepatic injury in chronic hepatitis C

Background and Aims : Relationships between chronic liver disease and trace metals have not been clearly understood. To examine connections between severity of hepatic fibrosis in chronic hepatitis C and copper, iron and zinc we measured the contents of these metals in liver tissue and serum in the patients.