Morphological differences between hepatocellular carcinoma and hepatocellular carcinomalike lesions

Fine-needle aspiration cytology to distinguish dysplasia from hepatocellular carcinoma with different grades

BACKGROUND

Distinguishing dysplasia from hepatocellular carcinoma (HCC) by fine-needle aspiration (FNA) cytology is difficult. The aim of this study was to diagnose HCC and the distinction of liver cell dysplasia from HCC with different grades by interpreting and scoring the cyto-morphological features.

METHODS

Eighty-three cirrhotic patients undertook a sonography-guided FNA and subsequent needle biopsy for the tumor. HCC was confirmed in 68 cases and cirrhosis with dysplasia in 15 cases by pathology and follow-up for longer than 2 years. Eighteen cytological features were scored as degree of one, two or three according to their presence or prominence.

RESULTS

Two cases of well-differentiated HCC were diagnosed as negative for HCC initially. The sensitivity, specificity, false positive, false negative and accuracy were 97%, 100%, 0%, 3% and 97.6% for FNA cytology in the diagnosis of HCC, respectively. The score of dysplasia was 20.8 +/- 1.3 (mean +/- SD) and lower than 26.2 +/- 3.4 in Edmondson's grade I HCC (P < 0.01), 28.9 +/- 2.9 in grade II HCC (P < 0.01), and 34.9 +/- 4.3 in grade III/IV HCC (P < 0.01). The score was also significantly lower in grade II HCC than in grade III/IV HCC (P < 0.01).

CONCLUSIONS

FNA yielded a high accuracy in the distinction of dysplasia from HCC with different grades. There is a good correlation in cyto-morphological scores of liver cell dysplasia and HCC with different grades. Dysplasia displayed the lowest score and the score increased in order from dysplasia to grade III/IV HCC.

Ultrastructural morphometrical and immunocytochemical analyses of hepatocyte nuclei from mice fed on genetically modified soybean

No direct evidence that genetically modified (GM) food may represent a possible danger for health has been reported so far; however, the scientific literature in this field is still quite poor. Therefore, we carried out an ultrastructural morphometrical and immunocytochemical study on hepatocytes from mice fed on GM soybean, in order to investigate eventual modifications of nuclear components of these cells involved in multiple metabolic pathways related to food processing. Our observations demonstrate significant modifications of some nuclear features in GM-fed mice. In particular, GM fed-mice show irregularly shaped nuclei, which generally represents an index of high metabolic rate, and a higher number of nuclear pores, suggestive of intense molecular trafficking. Moreover, the roundish nucleoli of control animals change in more irregular nucleoli with numerous small fibrillar centres and abundant dense fibrillar component in GM-fed mice, modifications typical of increased metabolic rate. Accordingly, nucleoplasmic (snRNPs and SC-35) and nucleolar (fibrillarin) splicing factors are more abundant in hepatocyte nuclei of GM-fed than in control mice. In conclusion, our data suggest that GM soybean intake can influence hepatocyte nuclear features in young and adult mice; however, the mechanisms responsible for such alterations remain unknown.

Hepatocellular carcinoma

Primary hepatocellular carcinoma is one of the 10 most common tumours, and the most common primary liver malignancy, in the world. In the majority of cases, it occurs against a background of hepatitis B or C viral infection and/or liver cirrhosis, and is associated with a dismal prognosis of a few months. Current treatments in routine clinical practice are surgical resection and liver transplantation, but these therapies are applicable to only a small proportion of patients and prolongation of survival is restricted. Other treatment options include intra-arterial chemotherapy, transcatheter arterial chemoembolisation, percutaneous ethanol injection, cryotherapy, thermotherapy, proton therapy, or a wide range of their possible combinations. The current lack of definitive data, however, limits the use of these therapies. Another option is gene therapy, which although in its infancy at the present time, may have a significant role to play in the future management of hepatocellular carcinoma.

Small hyperechoic nodules in chronic liver diseases include hepatocellular carcinomas with low cyclin D1 and Ki-67 expression

In spite of the importance of periodic screening for hepatocellular carcinoma (HCC) by ultrasonography (US) in patients with underlying liver disease, the clinicopathological characteristics of hyperechoic nodules have not been clearly evaluated. The aim of this study was to characterize the pathological and proliferating features of small hyperechoic nodules. Tissue specimens of 55 hyperechoic and 107 hypoechoic nodules less than 20 mm in diameter in patients with chronic liver disease were obtained by echo-guided needle biopsy and examined histopathologically. Of these, 42 (76%) hyperechoic and 56 (52%) hypoechoic nodules were diagnosed as HCC, and 82% of hyperechoic HCCs contained fatty change and/or clear cell change. In addition, immunohistochemical staining using cyclin D1, p53, and Ki-67 was examined. A high-level expression of cyclin D1 was found in only 5% of hyperechoic HCCs, in contrast to 38% of hypoechoic HCCs (P <.02). The labeling index of Ki-67 in hyperechoic HCCs was lower than in hypoechoic HCCs (4.2% vs. 8.9%; P <.003). However, there was no difference on p53 staining between them. Retrospective follow-up study revealed that hyperechoic nodules showed slow growth (doubling time, median: 1,403 days) initially, and came to show rapid growth (doubling time, median: 56 days). From these results, small hyperechoic nodules in chronic liver diseases are worth notice as candidates for well-differentiated HCC with low cyclin D1 and Ki-67 expression.

Areas of sinusoidal surface hepatocyte nuclear predominance in type C chronic hepatitis

AIMS/BACKGROUND

Thick hepatic plates have been considered one of the morphological characteristics of hepatocyte regeneration in cirrhotic nodules. They can be recognized by the sinusoidal surface predominance of their nuclei. We have investigated the prevalence of this in HBV and HCV infections.

METHODS AND RESULTS

This feature was more frequently present in type C chronic hepatitis with low activity of inflammation and low grade of fibrosis, than with type B chronic hepatitis. Additionally, this area of sinusoidal surface hepatocyte nuclear predominance (ASSHNP) was seen in zone II, rather than in periportal zones, in type C chronic hepatitis. Clinical data were analyzed statistically. Immunohistochemical reactivity of type IV collagen, laminin, Ulex europaeus agglutinin 1 lectin (UEA-1), and factor VIII-related antigen were increased in ASSHNP. Immunohistochemical staining of Ki-67 antigen was performed in order to assess the regenerative capacity of this area and showed a low level of regeneration. Ultrastructure of this area in type C chronic hepatitis showed a decrease in the number of mitochondria and an increase of nuclear pleomorphism together with basement membrane formation in the space of Disse.

CONCLUSION

Although the cause of these abnormalities was not clarified in this study, it is suggested that they are related to chronic hepatitis C virus (HCV) infection per se, rather than regeneration or inflammatory activity. These changes may be significant in HCV-associated hepatocarcinogenesis.

Laparoscopic prediction of hepatocellular carcinoma in cirrhosis patients

Previously, laparoscopic studies have not been successful in predicting the occurrence of small hepatocellular carcinoma because cirrhotic patients had not been separated into groups of those who developed small hepatocellular carcinoma under 3 cm in diameter, and those who did not. Retrospective examination with better separation of the two groups gave improved results. Of the 26 laparoscopic findings, only the presence of large complex regenerative nodules was closely associated with the occurrence of subclinical small hepatocellular carcinoma. The study of other cirrhotic patients with and without large complex regenerative nodules gave a cumulative hepatocellular carcinoma occurrence rate of 73% for patients who had these nodules by the third year after laparoscopy. In contrast, the rate for patients without such nodules was 6%, showing a significant difference (P < 0.05) between the two groups. We concluded that the laparoscopic finding of large complex regenerative nodules of liver cirrhosis can be used to predict the occurrence, or a complication, of subclinical small hepatocellular carcinoma.

Analysis of hyperplastic foci in livers with hepatocellular carcinomas by flow cytometry and AgNOR staining

The phase S ratio in cell cycles were analyzed in livers with hyperplastic foci (HPF) and in livers without HPF by nuclear DNA determinations using flow cytometry, and by staining with argyrophilic proteins of the nucleolar organizer region (AgNOR). Flow cytometric analysis was done on 50 fresh frozen specimens of livers resected from 50 patients with hepatocellular carcinoma (HCC). Paraffin sections from the same patients were analyzed using AgNOR staining. There were 25 cases each with and without HPF. We examined the stage of fibrosis and the grade of inflammatory activity according to the modified Scheuer and Desmet scale. The incidence of HCC recurrence among these patients was also studied. The average phase S ratio of the livers of the patients with HPF was 6.5 +/- 3.2%, and that of the livers of the patients without HPF was 4.0 +/- 2.5%. The ratio differed significantly between the two groups (P < 0.01). The average AgNOR score for HPF lesions of the HPF-positive cases was 1.60 +/- 0.34, that for non-HPF lesions in the HPF-positive cases was 1.29 +/- 0.12, and that for the HPF-negative cases was 1.19 +/- 0.14. Significant differences were found between the average AgNOR scores for HPF lesions of the HPF-positive cases and the non-HPF lesions of the HPF-positive cases (P < 0.01), as well as between the non-HPF lesions in the HPF-positive cases and the HPF-negative cases (P < 0.05). Severe fibrosis (stage 3) and cirrhosis (stage 4) were found in 76% of HPF-positive cases and 48% of HPF-negative cases. The livers of HPF-positive patients were significantly more cirrhotic than those of HPF-negative patients (P < 0.05). The association between HPF and the inflammatory grade was not significant (P > 0.05). The incidence of HCC recurrence among HPF-positive cases was significantly higher than that among the HPF-negative cases (P < 0.05). The average phase S ratio of the recurrent HPF-positive patients was 7.48 +/- 3.48%, significantly higher than that of HPF negative cases (5.57 +/- 3.06%, P < 0.05). Hyperplastic foci of the liver was shown to be a highly proliferative lesion. The proliferative activity of the non-HPF lesions in the HPF-positive patients was also higher than that of the HPF-negative patients. Hyperplastic foci tended to be present in cirrhotic livers, but it was not associated with the grade of inflammatory activity of the liver. Hyperplastic foci may represent an important predictor of recurrence after hepatic resection.

A clinicopathologic study of adenomatous hyperplasia of the liver in 209 consecutive cirrhotic livers examined by autopsy

BACKGROUND

Adenomatous hyperplasia (AH), also called macroregenerative nodule, of the cirrhotic liver is currently considered to be a preneoplastic or early neoplastic lesion in human hepatocellular carcinogenesis.

METHODS

The authors surveyed 209 consecutive cirrhotic livers from patients who had undergone autopsy at our laboratory during the last 18 years (1974-1991), and examined the prevalence and clinicopathologic characteristics of cirrhotic livers with AH. AH was classified into two types: ordinary and atypical. Ordinary AH (OAH) is devoid of hepatocellular atypia, whereas atypical AH (AAH) consists of atypical hepatocytes equivocal as to benignity and malignancy and occasionally contains overt malignant foci.

RESULTS

A total of 123 AH were found in 45 (21.5%) of the 209 cirrhotic livers; 38 AAH were found in 12 cirrhotic livers (5.7%), and 85 OAH was found in 41 cirrhotic livers (19.6%). Nineteen AAH contained overt malignant hepatocellular foci. Comparing the first 9 years (1974-1982) with the latter 9 years (1983-1991), 4 (3.8%) of 104 cirrhotic livers harbored AAH in the first period, and 8 (7.4%) of 105 cirrhotic livers contained AAH in the latter period. Sixteen (15.4%) of 104 cirrhotic livers harbored OAH in the first period, and 25 (23.8%) of 105 cirrhotic livers contained OAH in the latter period. Etiology of the 12 cirrhotic livers with AAH was as follows: 1 was hepatitis B virus, 10 were non-A non-B hepatitis virus, and 1 was primary biliary cirrhosis. Etiology of 41 cirrhotic livers with OAH was as follows: 16 were hepatitis B virus, 18 were non-A non-B hepatitis virus, and 7 were other causes. AAH occurred commonly in mixed nodular cirrhosis, whereas OAH occurred usually in macronodular or mixed nodular cirrhosis. All 12 cirrhotic livers with AAH were associated with hepatocellular carcinoma (HCC), particularly HCC of nodular type, whereas 17 cirrhotic livers with OAH were associated with HCC and the remaining 24 cirrhotic livers with OAH were not associated with HCC.

CONCLUSIONS

These results suggest that the number of cirrhotic livers with AH is increasing gradually, and that cirrhotic livers with AAH are characterized by the association with non-A non-B hepatitis virus as well as simultaneous occurrence of HCC. Thus, AAH may be an important preneoplastic lesion in cirrhotic livers associated with non-A non-B hepatitis virus (probably hepatitis C virus).

Histopathological and morphometric analysis of atypical adenomatous hyperplasia of human cirrhotic livers

Atypical adenomatous hyperplasia (AAH) is a hyperplastic parenchymal nodular change in the cirrhotic liver, in which overt hepatocellular carcinoma (HCC) occasionally arises. AAH is defined as a sizable hepatocellular nodule with a variable degree of hepatocellular atypia not regarded as HCC, and is different from ordinary adenomatous hyperplasia in which hepatocellular atypia is absent. In the present study, we attempted to evaluate carcinogenetic processes and to find histological variables which indicate malignant transformation in AAH, using 49 surgically resected or autopsied nodules. AAH frequently showed morphological heterogeneity. Atypical lesions within AAHs were divisible into the following three categories from overall histopathological appearances: malignant (A), equivocal (B), or non-malignant (C) lesions. Analysis of combination of these three lesions, which were frequently intermixed in a given AAH, suggested that B lesions appear subsequent to C lesions, and A lesions finally appear in AAH nodules. Among the 14 histological variables, enlargement, hyperchromasia and irregular contour of nuclei were found to correlate well with A lesions. Increased nuclear density, iron resistance, reduction of reticulin fibres, clear cell change, sinusoidal dilatation and presence of abnormal arteries were suggestive of A or B lesions. Nuclear deviation toward the sinusoids, acinar and compact arrangements, fatty change and Mallory's hyaline alone were not useful indicators of A or B lesions. These results indicate that AAH is a preneoplastic or borderline lesion in which overt HCC is likely to evolve through several steps. Although a needle liver biopsy is a useful tool for diagnosis of benign, equivocal and malignant hepatocellular nodular lesions, the needle biopsy specimen should be carefully evaluated by considering the morphological heterogeneity of the AAH and a variable combination of 14 histological variables.