Flow cytometric DNA analysis of hepatocellular carcinoma

Implications of Polyploidy and Ploidy Alterations in Hepatocytes in Liver Injuries and Cancers

Polyploidy, a condition in which more than two sets of chromosomes are present in a cell, is a characteristic feature of hepatocytes. A significant number of hepatocytes physiologically undergo polyploidization at a young age. Polyploidization of hepatocytes is enhanced with age and in a diseased liver. It is worth noting that polyploid hepatocytes can proliferate, in marked contrast to other types of polyploid cells, such as megakaryocytes and cardiac myocytes. Polyploid hepatocytes divide to maintain normal liver homeostasis and play a role in the regeneration of the damaged liver. Furthermore, polyploid hepatocytes have been shown to dynamically reduce ploidy during liver regeneration. Although it is still unclear why hepatocytes undergo polyploidization, accumulating evidence has revealed that alterations in the ploidy in hepatocytes are involved in the pathophysiology of liver cirrhosis and carcinogenesis. This review discusses the significance of hepatocyte ploidy in physiological liver function, liver injury, and liver cancer.

Hepatocyte Polyploidy: Driver or Gatekeeper of Chronic Liver Diseases

Polyploidy, also known as whole-genome amplification, is a condition in which the organism has more than two basic sets of chromosomes. Polyploidy frequently arises during tissue development and repair, and in age-associated diseases, such as cancer. Its consequences are diverse and clearly different between systems. The liver is a particularly fascinating organ in that it can adapt its ploidy to the physiological and pathological context. Polyploid hepatocytes are characterized in terms of the number of nuclei per cell (cellular ploidy; mononucleate/binucleate hepatocytes) and the number of chromosome sets in each nucleus (nuclear ploidy; diploid, tetraploid, octoploid). The advantages and disadvantages of polyploidy in mammals are not fully understood. About 30% of the hepatocytes in the human liver are polyploid. In this review, we explore the mechanisms underlying the development of polyploid cells, our current understanding of the regulation of polyploidization during development and pathophysiology and its consequences for liver function. We will also provide data shedding light on the ways in which polyploid hepatocytes cope with centrosome amplification. Finally, we discuss recent discoveries highlighting the possible roles of liver polyploidy in protecting against tumor formation, or, conversely, contributing to liver tumorigenesis.

Hepatocyte ploidy in cats with and without hepatocellular carcinoma

BACKGROUND

Domestic cats rarely develop hepatocellular carcinoma. The reason for the low prevalence is unknown. Reductions in hepatocellular ploidy have been associated with hepatic carcinogenesis. Recent work in mice has shown that livers with more polyploid hepatocytes are protected against the development of hepatocellular carcinoma. Hepatocyte ploidy in the domestic cat has not been evaluated. We hypothesized that ploidy would be reduced in peri-tumoral and neoplastic hepatocytes compared to normal feline hepatocytes. Using integrated fluorescence microscopy, we quantified the spectra of ploidy in hepatocellular carcinoma and healthy control tissue from paraffin embedded tissue sections.

RESULTS

Feline hepatocytes are predominantly mononuclear and the number of nuclei per hepatocyte did not differ significantly between groups. Normal cats have a greater number of tetraploid hepatocytes than cats with hepatocellular carcinoma.

CONCLUSIONS

Total hepatocellular polyploidy in normal cat liver is consistent with values reported in humans, yet cellular ploidy (nuclei per cell) is greater in humans than in cats. Tetraploid cat hepatocytes are predominantly mononuclear.

Mice With Increased Numbers of Polyploid Hepatocytes Maintain Regenerative Capacity But Develop Fewer Hepatocellular Carcinomas Following Chronic Liver Injury

BACKGROUND & AIMS

Thirty to 90% of hepatocytes contain whole-genome duplications, but little is known about the fates or functions of these polyploid cells or how they affect development of liver disease. We investigated the effects of continuous proliferative pressure, observed in chronically damaged liver tissues, on polyploid cells.

METHODS

We studied Rosa-rtTa mice (controls) and Rosa-rtTa;TRE-short hairpin RNA mice, which have reversible knockdown of anillin, actin binding protein (ANLN). Transient administration of doxycycline increases the frequency and degree of hepatocyte polyploidy without permanently altering levels of ANLN. Mice were then given diethylnitrosamine and carbon tetrachloride (CCl₄) to induce mutations, chronic liver damage, and carcinogenesis. We performed partial hepatectomies to test liver regeneration and then RNA-sequencing to identify changes in gene expression. Lineage tracing was used to rule out repopulation from non-hepatocyte sources. We imaged dividing hepatocytes to estimate the frequency of mitotic errors during regeneration. We also performed whole-exome sequencing of 54 liver nodules from patients with cirrhosis to quantify aneuploidy, a possible outcome of polyploid cell divisions.

RESULTS

Liver tissues from control mice given CCl₄ had significant increases in ploidy compared with livers from uninjured mice. Mice with knockdown of ANLN had hepatocyte ploidy above physiologic levels and developed significantly fewer liver tumors after administration of diethylnitrosamine and CCl₄ compared with control mice. Increased hepatocyte polyploidy was not associated with altered regenerative capacity or tissue fitness, changes in gene expression, or more mitotic errors. Based on lineage-tracing experiments, non-hepatocytes did not contribute to liver regeneration in mice with increased polyploidy. Despite an equivalent rate of mitosis in hepatocytes of differing ploidies, we found no lagging chromosomes or micronuclei in mitotic polyploid cells. In nodules of human cirrhotic liver tissue, there was no evidence of chromosome-level copy number variations.

CONCLUSIONS

Mice with increased polyploid hepatocytes develop fewer liver tumors following chronic liver damage. Remarkably, polyploid hepatocytes maintain the ability to regenerate liver tissues during chronic damage without generating mitotic errors, and aneuploidy is not commonly observed in cirrhotic livers. Strategies to increase numbers of polypoid hepatocytes might be effective in preventing liver cancer.

Surviving Acute Organ Failure: Cell Polyploidization and Progenitor Proliferation

In acute organ failure, rapid compensation of function loss assures survival. Dedifferentiation and/or proliferation of surviving parenchymal cells could imply a transient (and potentially fatal) impairment of residual functional performance. However, evolution has selected two flexible life-saving mechanisms acting synergistically on organ function recovery. Sustaining residual performance is possible when the remnant differentiated parenchymal cells avoid cell division, but increase function by undergoing hypertrophy via endoreplication, leading to polyploid cells. In addition, tissue progenitors, representing a subset of less-differentiated and/or self-renewing parenchymal cells completing cytokinesis, proliferate and differentiate to regenerate lost parenchymal cells. Here, we review the evolving evidence on polyploidization and progenitor-driven regeneration in acute liver, heart, and kidney failure with evolutionary advantages and trade-offs in organ repair.

The Polyploid State Plays a Tumor-Suppressive Role in the Liver

Most cells in the liver are polyploid, but the functional role of polyploidy is unknown. Polyploidization occurs through cytokinesis failure and endoreduplication around the time of weaning. To interrogate polyploidy while avoiding irreversible manipulations of essential cell-cycle genes, we developed orthogonal mouse models to transiently and potently alter liver ploidy. Premature weaning, as well as knockdown of E2f8 or Anln, allowed us to toggle between diploid and polyploid states. While there was no detectable impact of ploidy alterations on liver function, metabolism, or regeneration, mice with more polyploid hepatocytes suppressed tumorigenesis and mice with more diploid hepatocytes accelerated tumorigenesis in mutagen- and high-fat-induced models. Mechanistically, the diploid state was more susceptible to Cas9-mediated tumor-suppressor loss but was similarly susceptible to MYC oncogene activation, indicating that polyploidy differentially protected the liver from distinct genomic aberrations. This suggests that polyploidy evolved in part to prevent malignant outcomes of liver injury.

Prognostic significance of the DNA-index in liver transplantation for hepatocellular carcinoma in cirrhosis

OBJECTIVE

This study was conducted to evaluate the prognostic significance of the tumor DNA index in patients receiving liver transplantation for hepatocellular carcinoma (HCC) in cirrhosis.

BACKGROUND

In patients suffering from HCC in cirrhosis, the current selection for liver transplantation does not optimally achieve the goal to simultaneously maximize the number of viable transplant candidates and reject the smallest number of those who could have benefited. This is the first report on the prognostic significance of the tumor DNA index.

PATIENTS AND METHODS

From 1988 to 2007, liver transplantation for HCC in cirrhosis was performed in 246 consecutive patients. The DNA-index was determined by Feulgen staining and semiautomatical image analysis. Interpretation of DNA histograms followed the recommendations outlined in the European Society for Analytical Cellular Pathology consensus report on diagnostic DNA image cytometry.

RESULTS

A DNA-index <or=1.5 was detected in the HCC of 159 patients (65%). Five- and 10-year post-transplant survival rates in this group were 86% and 80%, respectively. The DNA-index exceeded 1.5 in 87 patients (35%). These patients had 5- and 10-year survival rates of 27% and 6%, respectively, which were significantly lower than in the DNA-index <or=1.5 group (P < 0.0001). On univariate analysis, DNA-index, vascular invasion, fulfillment of the Milan criteria, and histopathological grading were prognostic parameters. In the multivariate analysis, only DNA-index (odds ratio: 11.9; 95% confidence interval: 7.1-20.0; P < 0.0001) and vascular infiltration (odds ratio: 1.7; 95% confidence interval: 1.1-2.6; P < 0.01) were identified as prognostic variables.

CONCLUSION

This is the first study to describe the DNA-index as a strong prognostic indicator after liver transplantation for HCC in cirrhosis. At this time, determination of the DNA-index is likely to be the most promising diagnostic tool in the selection of transplant candidates.

Prognostic molecular markers in hepatocellular carcinoma: a systematic review

Hepatocellular carcinoma (HCC) is the fifth commonest malignancy worldwide and its incidence is rising. Surgery, including transplantation, remains the only potentially curative modality for HCC, yet recurrence rates are high and long-term survival poor. The ability to predict individual recurrence risk and subsequently prognosis would help guide surgical and chemotherapeutic treatment. As understanding of hepatocarcinogenesis has increased, the myriad of genetic and molecular events that drive the hepatocarcinogenic disease process, including angiogenesis, invasion and metastasis, have been identified. This systematic review examines the evidence from published manuscripts reporting the prognostic potential of molecular biomarkers in hepatocellular carcinoma. In summary, a number of molecular biomarkers with prognostic significance have been identified in hepatocellular carcinoma. Not only might these molecules allow more accurate prediction of prognosis for patients with HCC, but they may also provide targets for potential therapeutic agents.

Genetics of hepatocellular tumors

Numerous genetic alterations are accumulated during the process of hepatocarcinogenesis. These genetic alterations can be divided into two groups. The first set of genetic alterations is specific of hepatocellular tumor risk factors. It includes integration of hepatitis B virus (HBV) DNA, R249S TP53 (tumor protein p53) mutation in aflatoxin B1-exposed patients, KRAS mutations related to vinyl chloride exposure, hepatocyte nuclear factor 1alpha (HNF1alpha) mutations associated to hepatocellular adenomas and adenomatosis polyposis coli (APC) germline mutations predisposing to hepatoblastomas. The second set of genetic alterations are etiological nonspecific, it includes recurrent gains and losses of chromosomes, alteration of TP53 gene, activation of WNT/beta-catenin pathway through CTNNB1/beta-catenin and AXIN (axis inhibition protein) mutations, inactivation of retinoblastoma and IGF2R (insulin-like growth factor 2 receptor) pathways through inactivation of RB1 (retinoblastoma 1), P16 and IGF2R. Comprehensive analyses of these genetic alterations have defined two pathways of hepatocarcinogenesis according to the presence or the absence of chromosomal instability. Hepatitis B virus and poorly differentiated tumors are related to chromosome instable tumors associated with frequent TP53 mutations, whereas non-HBV and well-differentiated tumors are related to chromosomal stable samples that are frequently beta-catenin activated. These classifications have clinical relevance as genetic alterations may also be related to prognosis.

Biological characteristics of HCC by ultrasound-guided aspiration biopsy and its clinical application

AIM: To probe the pathological biological characteristics of hepatocellular carcinoma (HCC) by the ultrasound-guided aspiration biopsy and assess the clinical application value of this method.

METHODS: The biopsy and DNA analysis by flow cytometry (FCM) were taken in 46 cases with HCC nodules, including 26 cases and 20 cases with nodules ≤ 3 cm and > 3 cm in diameters respectively, and 12 cases with intrahepatic benign hyperplastic nodules. They were taken in 22 cases of 46 cases with HCC before and after the therapy. Fine-needles and automatic histological incised biopsy needles were used. The fresh biopsy tissue was produced into the single cell suspension, which was sent for DNA detection and ratio analysis of cell period. The ratio of each DNA period of cell proliferation of each group was calculated and compared with each other. The DNA aneuploid (AN) and apoptosis cell peak were observed and their percentages were calculated.

RESULTS: The ratios of S and G₂/M periods of DNA, which reflect cell hyperproliferation, in the group with HCC tumors > 3 cm in diameter were markedly higher than those of the group with HCC nodules ≤ 3 cm in diameter and the group with the benign hyperplastic nodules (P < 0.01 except A:B of S period, P < 0.05). The ratios of the middle group were also apparently higher than those of the latter group (P < 0.01). The ratio of DNA AN of 46 cases with HCC nodules was 34.8% (16/46). None of the cases with the intrahepatic hyperplastic nodules appeared AN. The DNA AN appeared more apparently with the growth of the tumors. The AN ratio of the group with tumors > 3 cm in diameter was 55% (11/20), markedly higher than that of the group with tumors ≤ 3 cm in diameter which was 19.2% (5/26) (P < 0.01). The FCM DNA analysis of 22 specimens of hepatic carcinoma tissue before therapy showed that the aneuploid peaks appeared in 5 cases (22.7%). The ratio of G₁ period rose after therapy while the S period and G₂/M ratios fell (P < 0.01). The aneuploid peak disappeared in the 5 cases after the therapy, while the apoptosis peaks in 12 cases (54.5%) appeared.

CONCLUSION: Addition to supply the information of the pathological morphology of the tumor, the ultrasound-guided fine-needle aspiration tissue could be sent for FCM DNA analysis to comprehend its pathological biological characteristics. This can not only provide the clinic the reliable information about the occurrence, development, diagnosis, curative effect and prognosis of tumors but also supply biological information for clinic to choose therapeutic schemes.

Flow cytometric DNA analysis on fine needle aspiration biopsies of liver lesions

Flow cytometric DNA analysis on fine needle aspiration biopsies of liver lesions The DNA cell content of 39 fine needle aspiration biopsies (FNAs) from five benign liver lesions, nine hepatocellular carcinomas (HCCs), and 25 metastatic tumours was analysed in a prospective fashion by flow cytometry (FCM). All benign lesions were diploid. Aneuploidy was found in five (55.6%) HCCs and in nine (36%) metastatic tumours. DNA index (DI) differences were not significant. The S-phase fraction (SPF) was higher in the malignant tumours, both combined (P < 0.02) and separated primary and metastatic (P < 0.05). We could not demonstrate an association between diploidy and percentage of benign hepatocytes in the smears of malignant tumours. The serum alpha-fetoprotein (AFP) level did not correlate with ploidy, DI, or SPF in the HCCs. In conclusion, ploidy and DI do not discriminate between benign and malignant liver lesions, but the SPF is higher in malignant tumours. DNA analysis does not help to distinguish primary from metastatic liver tumours. The presence of benign hepatocytes in samples from malignant tumours does not seem to influence the analysis of ploidy by FCM.

Usefulness of tumor pressure as a prognostic factor in cases of hepatocellular carcinoma where the diameter of the tumor is 3 cm or less

BACKGROUND

The current study was designed to determine the usefulness of pretreatment tumor pressure as a new prognostic factor in patients with small hepatocellular carcinoma (HCC; 3 cm or smaller in diameter).

METHODS

The study included 39 patients with small HCC in whom tumor pressure was determined. They underwent percutaneous ethanol (with Lipiodol) injection therapy (Lp-PEI) or transcatheter arterial embolization (TAE) of the hepatic artery. Tumor pressure was determined percutaneously under ultrasonographic guidance. The factors analyzed were age, gender, mean blood pressure, the presence/absence of antibody to hepatitis C virus (anti-HCV), alcohol abuse, Child's classification, the presence/absence of esophagogastric varices, serum alpha-fetoprotein (AFP) level, tumor size, number of tumors, degree of tumor differentiation, the presence/absence of tumor capsule, tumor pressure, and the method of treatment. Multivariate analysis using Cox proportional hazards model was conducted on the factors that may have affected prognosis (P < 0.25) according to the univariate analysis using a proportional hazards model.

RESULTS

The rates of local and distant recurrence were higher (P < 0.01, P < 0.01, respectively) and the survival rate was lower (P = 0.03) in patients with high tumor pressure than in those with low tumor pressure. Multivariate analysis revealed that tumor pressure (P < 0.01), AFP level (P = 0.01), and age (P = 0.01) were significant predictive factors associated with local recurrence. Tumor pressure (P < 0.01) and AFP level (P < 0.01) were both significantly associated with distant recurrence. The only significant predictive factor associated with survival rate was tumor pressure (P < 0.04).

CONCLUSIONS

The current study revealed that tumor pressure was associated significantly with survival rates after Lp-PEI or TAE in patients with small HCC. There were also significant predictive factors associated with local recurrence, these being tumor pressure, AFP level, and age, and with distant recurrence, namely, tumor pressure and AFP level. Tumor pressure measured before the initial treatment of patients with small HCC may be a useful new prognostic factor.

Expression of smooth muscle calponin in tumor vessels of human hepatocellular carcinoma and its possible association with prognosis

BACKGROUND

Hepatocellular carcinoma (HCC) is a vascular-rich tumor. The tumor vessels in HCC were demonstrated to have alpha-smooth muscle actin positive smooth muscle cells (SMCs). However, it is unclear whether the SMCs in the wall of the tumor vessels are differentiated or undifferentiated. Basic calponin is an actin-, tropomyosin-, and calmodulin-binding protein, and expression of the calponin gene in SMCs has been recognized as one of the late stage differentiation markers of SMCs. The authors investigated the differentiation state of SMCs in tumor vessels by immunohistochemical examination of calponin in patients with HCC, and whether it is associated with the patients' prognosis.

METHODS

Tumor and nontumor tissues were obtained from 75 patients with HCC who underwent radical hepatic resection. The differentiation state of the smooth muscle cells were evaluated based on the expression level of calponin, an actin-binding protein, using immunohistochemistry and reverse transcription-polymerase chain reaction analysis. The disease free survival (DFS) rates were estimated according to the Kaplan-Meier method comparing groups of patients with calponin positive and negative tumor vessels. A multivariate analysis based on the Cox proportional hazards regression model was performed to estimate whether the expression of calponin is an independent prognostic factor.

RESULTS

In the 75 patients with HCC examined, 36 patients (48%) possessed calponin positive SMCs, and the remaining 39 (52%) did not. There were no significant differences in either clinical or pathologic factors between the two groups of patients. The 5- and 8-year DFS rate of the patients with calponin positive vessels were 37% and 26%, respectively. These values were significantly higher (11% and 5%) than those of patients with calponin negative vessels. Gender, TNM classification, perioperative transfusion, and calponin expression were found to be independent prognostic factors for DFS.

CONCLUSIONS

Immunohistochemical examination of the calponin expression in the tumor vessels is a new and useful means to predict the prognosis of HCC patients after hepatic resection.

Clinicopathologic analysis of stage II-III hepatocellular carcinoma showing early massive recurrence after liver resection

BACKGROUND AND AIMS

Prognosis after hepatectomy for hepatocellular carcinoma (HCC) has been improved by progress in the evaluation of hepatic functional reserve, surgical techniques and perioperative management. However, even when curative resection is performed at a relatively early stage, a considerable number of patients develop early intrahepatic and/or extrahepatic recurrence postoperatively. This study analyzed the clinicopathologic features of HCC with early recurrence.

METHODS

We reviewed records of 513 consecutive patients who had undergone liver resection for HCC. There were 48 deaths within a year after surgery from recurrence, including 21 patients with stage II or III HCC (group I). Clinicopathologic parameters of group I patients were compared with those of 188 patients (group II) who developed recurrence following resection of stage II or III HCC and died more than 1 year after surgery.

RESULTS

On univariate analysis, age, tumor diameter (phi), alpha-fetoprotein (AFP):phi and protein induced by vitamin K absence or antagonist II (PIVKA-II):phi were significantly greater in group I than in group II. Macroscopic portal vein invasion, microscopic vascular invasion, intrahepatic metastasis, poor differentiation, pleomorphism, sarcomatous change, vascular lake, and angiographic condensed pooling were more frequently observed in group I than group II. Five independent determinants were selected by multivariate analysis: AFP:phi, histologic pleomorphism, sarcomatous change, vascular lake and angiographic condensed pooling.

CONCLUSIONS

Highly malignant HCC with extremely poor prognosis exhibits peculiar clinicopathologic characteristics, particularly histologic immaturity, and can be predicted by preoperative indicators such as markedly elevated tumor marker concentrations and condensed pooling on angiography.

Analysis of three-dimensional architecture in Feulgen-stained fine-needle liver aspirates, using confocal scanning laser microscopy

Early and accurate diagnosis of hepatocellular carcinoma in liver nodules using fine-needle aspiration biopsy can still pose difficulties, particularly in cirrhotic nodules containing dysplastic hepatocytes. Loss of architectural clues, which may aid diagnosis, can be overcome by using confocal scanning laser microscopic examination of tissue fragments in smears without the need for further processing of slides. The basic fuchsin of the Feulgen method resulted in excellent confocal images without the need for further processing of the smears. Clear morphological differences in three-dimensional reconstructions of optically sectioned tissue fragments were demonstrated in normal, hyperplastic, and malignant smears as an aid to diagnosis.

Chromosomal changes and clonality relationship between primary and recurrent hepatocellular carcinoma

BACKGROUND & AIMS

Hepatocellular carcinoma (HCC) is highly malignant and prone to recur after surgical treatment. Differentiation between a true relapse of HCC and a second primary tumor is of clinical importance. However, no convenient method is currently available.

METHODS

Comparative genomic hybridization (CGH) was used to analyze 31 pairs of initial and recurrent HCC samples obtained from patients undergoing 2 consecutive surgeries. The resulting chromosomal aberration profiles were used as genomic fingerprints to determine tumor clonalities and their relationships.

RESULTS

Eleven recurrent tumors with high clonal relationship (CR) values (>0.95) were found to be relapsed HCCs, and 11 tumors with CR values close to 0 were found to be second primary HCCs. The other 9 paired samples had inconclusive CR values between 0.95 and 0.4. Two were confirmed by hepatitis B virus integration and X chromosome inactivation analysis to be de novo cancers (CR values, 0.35 and 0. 23, respectively). Initial HCCs that subsequently relapsed accumulated more chromosomal aberration events than those that developed de novo HCC (mean, 16.1 +/- 4.5 vs. 5.4 +/- 4.8 events; P < 0.01). Also, they more frequently showed gains on chromosome arms 3q, 6p, 8q, and 17q and losses on 4q and 16p.

CONCLUSIONS

CGH is useful for chromosomal aberration study and tumor clonality analysis. More and characteristic genomic changes in the initial HCC suggest that subsequent tumor recurrence is a true relapse.

Microsatellite instability associated with hepatocarcinogenesis

BACKGROUND/AIMS

The biological and clinicopathological significance of microsatellite instability in hepatocellular carcinoma still remains to be determined. The aim of this study was to assess the role of microsatellite instability in hepatocarcinogenesis.

METHODS

Genomic DNA extracted from 38 fresh samples of hepatocellular carcinoma was amplified by polymerase chain reaction using 29 fluorescence-labeled microsatellite markers and analyzed using a semi-automated laser scanning system. Associations between the incidence of replication error and the clinicopathological features of hepatocellular carcinoma were evaluated. Since reference DNA was extracted from corresponding fresh samples of non-cancerous liver tissue, the incidence of microsatellite instability in non-cancerous liver tissues was not assessed in this study.

RESULTS

Four (11%) hepatocellular carcinomas had a replication error in one or two microsatellite markers; they were all poorly differentiated hepatocellular carcinomas. The incidence of replication error correlated significantly with the histological differentiation of the tumor (p<0.05) and with portal vein involvement (p<0.05). All four hepatocellular carcinomas with replication errors showed loss of heterozygosity in one or more of the 29 markers we examined. No replication errors were detected in six markers in the coding regions of the BAX, insulin-like growth factor II receptor, transforming growth factor-beta type II receptor, E2F-4, hMSH3 and hMSH6 genes.

CONCLUSIONS

The results of this study indicate that: (1) microsatellite instability is a rare event during hepatocarcinogenesis and may be specifically associated with progression of hepatocellular carcinoma; and (2) frame-shift mutation in the above six genes is not a common mechanism involved in progression of this cancer.

Resection versus transplantation for hepatocellular carcinoma

Hepatocellular carcinoma is responsible for more than 1 million deaths per year worldwide and thus remains a challenging medical problem. It causes few or no symptoms and the tumour frequently reaches an enormous size by the time of diagnosis in countries where screening is seldom used. It is generally resistant to commercially available anti-neoplastic agents and radiation therapy. The principal treatment continues to be resection, either partial or complete, with liver transplantation. However, less than one-third of patients are surgical candidates for either resection or transplantation at the time of clinical presentation. This review will address the results observed following resection or transplantation for hepatocellular carcinoma.

Surgical treatment and outcome in patients with a hepatocellular carcinoma greater than 10 cm in diameter

BACKGROUND

Hepatocellular carcinoma (HCC) over 10 cm in diameter at the time of diagnosis continues to account for a number of patients undergoing hepatic resection. This study evaluated the clinicopathological features and outcome following surgery for large HCC.

METHODS

Forty patients with a large HCC (greater than 10 cm) (group 1) resected between 1991 and 1996 were studied retrospectively. They were compared with 245 patients who had smaller HCCs (10 cm or less) (group 2).

RESULTS

No patient in group 1 had hepatitis C infection compared with 22.9 per cent in group 2 (P=0.001). Patients in group 1 were significantly younger, had higher alpha-fetoprotein levels (16750 versus 1864 ng/ml; P < 0.001), better liver function, a higher incidence of multiple tumours (27 of 40 versus 42.0 per cent; P=0.003) and venous invasion (35 of 40 versus 52.2 per cent; P < 0.001), and underwent more major resections (37 of 40 versus 26.5 per cent; P < 0.001) than those in group 2. Morbidity and mortality rates and hospital stay were comparable in the two groups. For group 1, the 1-, 3- and 5-year disease-free survival rates were 42, 30 and 28 per cent respectively. Multiple tumours, venous invasion and impaired liver function were factors associated with recurrence.

CONCLUSION

Large HCC had specific clinicopathological features. In selected patients, resection is safe and offers the chance of long-term disease-free survival.

Retrospective evaluation of DNA ploidy of hepatocarcinoma on cytologic samples

DNA ploidy was evaluated by image cytometry in a series of 84 hepatocellular carcinomas diagnosed by fine-needle aspiration biopsy. In the series were included eight cases originally diagnosed as suspect and reclassified as well-differentiated hepatocarcinoma. The study was retrospectively performed on Papanicolaou-destained, Feulgen-restained smears. The 5c exceeding rate and the visual interpretation of the corresponding histograms were evaluated and compared with size of the tumors, serum alpha-fetoprotein values, hepatic functional staging, and patient survival. Sixty-eight cases were aneuploid and 16 euploid (9 diploid and 7 polyploid). Four of the eight cytologically suspect cases were aneuploid. Statistical analysis showed an association between size and cytologic grading, 5c exceeding rate and cytologic grading, and between aneuploidy and multiple tumors; in a Cox multivariate DNA content analysis, aneuploidy and multiple tumors were the two prognostically significant variables. DNA ploidy evaluation by static cytometry of hepatic tumors may be useful in the diagnosis on cytologic samples and could represent an independent prognostic parameter in predicting the survival outcome of patients with hepatocellular carcinoma.

Genomic fluidity is a necessary event preceding the acquisition of tumorigenicity during spontaneous neoplastic transformation of WB-F344 rat liver epithelial cells

The genomic evolution of a cohort of WB-F344 rat liver epithelial cell lineages undergoing spontaneous neoplastic transformation was followed to define the mechanistic relationship between genomic instability and progression to the neoplastic phenotype. Eighteen independent populations of WB-F344 cells (initiated from a single diploid-founding population) were subjected to 12 cycles of selective growth at confluent cell density, and cellular DNA contents were measured after each selection cycle. Flow cytometry demonstrated significant gains in the amount of G1 DNA after selection cycles 3, 6, and 7 in 44% (8 of 18), 89% (16 of 18), and 39% (7 of 18) of the cell populations, respectively. All populations subsequently lost DNA and returned to a diploid or pseudo-diploid DNA content within 1 to 2 selection cycles after the appearance of an increased DNA content. Additionally, appearance and subsequent disappearance of aneuploid or tetraploid subpopulations was observed in 11% (2 of 18) and 83% (15 of 18) of the experimental lineages, respectively. Although perturbations of G1 DNA content were apparent as early as selection cycle 3, at least 8 cycles of selective growth were required for the acquisition of tumorigenicity. While the independent lineages demonstrated significant fluctuations in G1 DNA content between selection cycles 3 and 8, the majority (11 of 13) of the populations contained a diploid or pseudo-diploid DNA content at the time tumorigenicity was expressed. Genomic instability preceded the acquisition of tumorigenic potential in rat liver epithelial cells subjected to selective growth conditions of maintenance at confluence, and may be required for its expression.

Prognostic significance of pathological and biological factors in hepatocellular carcinoma

Prognostic factors in hepatocellular carcinoma (HCC) conventionally consist of staging with the tumour node metastasis system and grading by tumour cellular differentiation. There are also other factors useful in prognostication but most of them are clinical. With new discoveries in the pathobiology of cancers and introduction of new medical technology, pathological and biological factors of HCC in relation to prognosis have been studied quite extensively. Morphological features of the tumour, both gross and histological, have been found to be significantly related to tumour recurrence and patient survival. Recently, applications of new antibodies and techniques have enabled studies on cellular proliferation using different antibodies such as those for proliferating cell nuclear antigen and Ki-67 protein. These studies on cellular proliferation, as well as assessment of argyrophilic nucleolar organizing regions, have been shown to provide good prognostic significance. Flow cytometric studies on DNA ploidy and studies on expression of genes including the p53 gene, hormone receptors and others show less unanimous results in their prognostic significance. The influence of gender on survival is also reviewed. In conclusion, pathological and biological factors are useful and help to guide clinicians in the management of patients and in assessment of long-term prognosis.

Surgical results in patients with dual hepatitis B- and C-related hepatocellular carcinoma compared with hepatitis B- or C-related hepatocellular carcinoma

BACKGROUND

The purpose of our study was to report on the surgical outcomes of patients with hepatocellular carcinoma (HCC) with dual hepatitis B virus (HBV) and hepatitis C virus (HCV) infections and to assess the differences in the surgical results between those patients and the patients with hepatitis B- or hepatitis C-related HCC.

METHODS

The operative outcomes of 13 patients with hepatitis B surface antigen (HBsAg)-positive and hepatitis C antibody (HCV Ab)-positive (the BC-HCC group) results, 57 patients with HBsAg-positive and HCV Ab-negative (the B-HCC group) results, and 34 patients with HBsAg-negative and HCV Ab-positive (the C-HCC group) results, who had undergone hepatic resection from 1991 to 1995, were compared.

RESULTS

The operative mortality rate within 1 month after operation for patients with BC-HCC was 7.7%. No statistically significant difference was found compared with the patients with B-HCC and C-HCC (5.3% and 5.9%, respectively). The postoperative course of patients with BC-HCC was complicated by liver failure, postoperative ascites, and wound infection in one patient each. Also, no statistically significant difference was found among the groups (23.1%, 22.8%, and 20.5% for patients with BC-HCC, B-HCC, and C-HCC, respectively). The overall 1-, 3-, and 5-year survival rates of patients with BC-HCC in this series were 75%, 50%, and 40%, respectively. The postoperative recurrence rate was 66.7%. No statistically significant differences were found between the various groups of the virus-related HCC on the overall survival rate and disease-free survival rate.

CONCLUSIONS

Hepatic resection for HCC in patients with dual HBV and HCV infections was associated with slightly higher operative morbidity and mortality rates, but there were no statistical differences compared with hepatitis B- or C-related HCC regarding the survival and recurrence rates.

Progression of hepatocellular carcinoma as reflected by nuclear DNA ploidy and cellular differentiation

BACKGROUND/AIMS

Intratumor heterogeneity of DNA ploidy within a single hepatocellular carcinoma is not well understood. The present study was designed to examine the histologic distribution of intratumor DNA ploidy in hepatocellular carcinomas of different growth types in relation to cell differentiation.

METHODS

Twenty patients (16 men and four women; mean age, 60.2 years) with hepatocellular carcinoma (mean diameter, 4.3 cm) were studied. One hundred and twenty-seven samples from different sites of each tumor were analyzed by determination of the nuclear DNA content and histological examination.

RESULTS

The DNA ploidy was heterogeneous in nine (45%) of the 20 tumors. Five tumors had a mixture of diploid and aneuploid regions, and the remaining four consisted of aneuploid regions with different DNA indices. There was no significant difference in patient characteristics between the heterogeneous and homogeneous groups. A significant correlation was found between tumor growth type and the incidence of heterogeneity. Only 16% of single nodular carcinomas without intratumor septal formation exhibited heterogeneity, while single nodular tumors with septal formation or confluent multinodular tumors were associated with high incidences of different DNA ploidy patterns or DNA indices. There was no aneuploidy in well-differentiated foci, while aneuploidy was frequently found in moderately or poorly differentiated foci (incidences of 67% and 74%, respectively).

CONCLUSIONS

Heterogeneity of DNA ploidy may develop along with changes in growth pattern and cell dedifferentiation or by confluence of nodules originating from different tumor cell clones.

Loss of heterozygosity of the retinoblastoma gene in liver cirrhosis accompanying hepatocellular carcinoma

Carcinogenesis is a multistep process. Most hepatocellular carcinoma (HCC) is preceded by liver cirrhosis, but the genetic changes involved in cirrhosis are not known well. The present study was conducted to evaluate aberration of the retinoblastoma (RB) gene in HCC and adjacent non-tumorous liver using 22 patients with chronic liver damage accompanying HCC. The specimens obtained by microdissection from paraffin-embedded tissues were analyzed using an assay based on the polymerase chain reaction for highly polymorphic nucleotide sequences of microsatellites in the RB gene. Out of 22 cases, 15 showed constitutional heterozygosity for the microsatellite markers. In 11 (73.3%) of these 15 informative cases, the primary HCC foci showed loss of heterozygosity (LOH). In 8 of these 11 doubly informative (informative and LOH-positive in primary HCC) cases, LOH was found in 20 (64.5%) of 31 microdissected non-tumorous foci. All of the non-tumorous foci showing RB loss were cirrhotic lesions but there were no foci of chronic hepatitis. The remaining 4 cases without LOH in HCC foci showed no LOH in non-tumorous lesions. In our study, LOH of the RB gene was frequently observed in liver cirrhosis surrounding tumor.

Cellular DNA content and histopathological analysis in hepatocellular carcinoma with multiple nodules

Multiple tumors within the liver are a characteristic feature of hepatocellular carcinoma (HCC). This study investigated alterations in the histologic type and DNA content of multiple nodules of HCC. Both a pathologic examination and flow cytometric DNA analysis were performed on 49 resected specimens of multinodular HCC. The results showed that 35 cases had multiple metastatic satellite nodules around the main tumor (group 1), while 14 had two solitary nodules in different segments without satellite nodules (group 2). In group 1, 28 out of 35 (80.0%) showed a single DNA index while 7 (20.0%) revealed two different DNA contents in the main tumor. The histological type, cytological grade, and DNA index were equivalent between the main and satellite tumors in 100%, 88.6%, and 97.1% of the cases, respectively. In group 2, all tumors showed a single histological type, cytological grade, and DNA index in each nodule. The histological type was identical in 85.7% of the pairs of nodules, but the cytological grade and DNA index were different in 42.9% and 85.7%, respectively. The patients in group 2 showed a significantly higher 5-year survival rate than that in group I (64.8% vs 27.2%, P < 0.05). This study thus indicates that the cytological grade and DNA content are useful in distinguishing multicentric occurrence from intrahepatic metastasis in HCC.

Partial hepatic resection for hepatocellular carcinoma

This review summarizes the efficacy of the most common therapeutic option for hepatocellular carcinoma (HCC), partial hepatic resection, taking into account not only its antitumoural effect, but also its consequences on survival. Partial hepatic resection results in 5 year survival rates as high as 45% in more favourable subgroups having: small tumours, well-differentiated tumours, unifocal tumours, a lack of vascular invasions, an absence of cirrhosis, and the fibrolamellar variant. Resection has been limited primarily by low resectability rates and recurrent disease. However, surgical resection in the form of partial hepatectomy is the preferred treatment for HCC. The early detection of tumours by screening high-risk populations is crucial. During the 12 year period between 1983 and 1994, hepatic resections were carried out in 382 patients with HCC. One hundred and fifty-three (40%) had HCC smaller than 5 cm in diameter. There were 294 male and 88 female patients, with an average age of 52.3 years. Among them, 45% had liver cirrhosis and 73% were positive for hepatitis B surface antigen. Two hundred and eighteen (57%) were positive for hepatitis C virus circulating antibodies (since 1991). Operative mortality was 3.9%. The overall survival rates at 1, 3 and 5 years were 71, 52 and 46%, respectively. Sex, cirrhosis, Child's staging, surgical procedure, blood loss, pathological pattern, presence of capsule, surgical margin and DNA ploidy appeared to be factors not related to prognosis. However, alpha-fetoprotein level, size (whether less than or greater than 5 cm), and vascular invasion were factors which significantly affect survival.

Correlation of hepatitis virus serologic status with clinicopathologic features in patients undergoing hepatectomy for hepatocellular carcinoma

BACKGROUND

This study investigated the relationship between clinicopathologic features and various viral serologies in patients who underwent hepatectomy in the treatment of hepatocellular carcinoma (HCC).

METHODS

Two hundred two patients were allocated to four groups, according to their positivity or negativity for hepatitis B surface antigen (HBsAg) and hepatitis C virus antibody (HCVAb): Group I (HBsAg[-], HCVAb[+], n = 151), Group II (HBsAg[+], HCVAb[-], n = 27), Group III (HBsAg[-], HCVAb[-], n = 20), or Group IV (HBsAg[+], HCVAb[-], n = 4). The mean age of the HBsAg positive patients (Groups II and IV) was 10 years younger than that of the HBsAg negative patients (Groups I and III).

RESULTS

The male-to-female ratio was higher in HCVAb negative groups (II and III). The HCVAb positive groups (I and IV) had a significantly poorer hepatic reserve and smaller resections than the HCVAb negative groups. Because the tumors were more advanced (as determined by TNM staging) in Group II, the 3-year crude and disease free survival rates were lower in Group II than in Group I. However, HCVAb negative groups (II and III), when compared at 5 years with the limited subsets of patients who had tumors at earlier stages or a curative resection, had significantly better crude and disease free 5-year survival rates than the HCVAb positive group (I).

CONCLUSIONS

Clinicopathologic features differ from one another in accordance with the viral seromarkers in HCC patients. Significantly better crude and disease free survival after complete resection were promising results for patients with non-HCV-related HCC. By comparison, for patients with HCV-related HCC, the risk of intrahepatic recurrences never subsided even in later years after complete resection. Therefore, posthepatectomy follow-up management should be individualized depending on the viral serologic status of HCC patients.

Heterogeneity of DNA content in multiple synchronous hepatocellular carcinomas

Heterogeneity of DNA content in multiple hepatocellular carcinomas (HCCs) was investigated by flow cytometry in 62 tumours from 26 patients who had undergone surgical treatment for multiple synchronous HCCs. Heterogeneity of DNA content was defined (a) when tumours had a different DNA ploidy pattern or (b) when the difference in the DNA index of the aneuploid clone was more than 0.1. A tumour with DNA aneuploidy was observed in 17 (66%) of the 26 patients. Heterogeneity of the DNA content was demonstrated in 12 (46%) out of 26 patients: in ten cases by definition (a) and in two cases by definition (b). Histological examination revealed that, of the 12 patients with a heterogeneous tumour DNA content, seven (58%) had a heterogeneous and the remaining five (42%) had a homogeneous type and grade of differentiation among the tumours, showing the absence of a relationship between histological heterogeneity and DNA content. The present results suggest the clinical relevance of DNA content analysis for identifying the clonal origin of multiple HCCs.

DNA ploidy study of resected hepatocellular carcinoma in cirrhotic liver

BACKGROUND/AIMS

Results of several studies on DNA ploidy as a prognostic indicator in hepatocellular carcinoma are contradictory. The present study analysed the correlations between DNA ploidy of resected hepatocellular carcinoma and tumour characteristics, tumour recurrence, risk factors and survival.

METHODS

Tumoural DNA ploidy of hepatocellular carcinomas from 37 patients with cirrhosis who underwent curative tumour resection was studied by flow cytometry.

RESULTS

A diploid pattern was found in 23 hepatocellular carcinomas (62.2%) and an aneuploid pattern in 14 (37.8%). The tumour recurrence rate did not differ statistically between diploid (69.6%) and aneuploid (50%) hepatocellular carcinomas. The only prognostic variable with significant difference in DNA pattern was the histologic tumour type; the majority of non-trabecular tumours were aneuploid while most trabecular hepatocellular carcinomas had a diploid DNA pattern. Actuarial survival at 1, 2, 3 and 4 years of patients with diploid and aneuploid tumours was 69.6%, 40.6%, 16.2% and 0%, and 69.3%, 59.4%, 49.5% and 32.9%, respectively (log rank p = 0.1927).

CONCLUSION

These results indicate that DNA ploidy has no prognostic value in hepatocellular carcinoma.

Alteration of DNA ploidy and cell nuclearity in human hepatocellular carcinoma associated with HBV infection

BACKGROUND/AIMS

Hepatocellular carcinoma usually arises in cirrhotic livers as a complication of chronic liver disease, and may show a variable trend towards increasing ploidy. The aim of this study was to investigate possible associations between different etiological factors, particularly hepatitis B virus and hepatitis C virus infection, and alteration of DNA-ploidy and nuclearity of neoplastic hepatocytes.

METHODS

DNA-ploidy, the percentage of binucleated cells in the total cell population and the fraction of mononucleated hepatocytes in the polyploid compartment were assessed by image cytometry on cellular suspensions obtained by fine-needle biopsy from 60 hepatocellular carcinomas in patients whose viral status had previously been assessed.

RESULTS

Significantly higher DNA-ploidy values (p = 0.005), with a reduction in the percentage of binucleated hepatocytes (p = 0.003) and an increase in the fraction of mononucleated hepatocytes in the polyploid compartment (p < 0.0001), were found in hepatocellular carcinoma with actual or previous hepatitis B virus infection (including also HCV+ve patients) in comparison to those not associated with hepatitis B virus infection, but not when HCV+ve hepatocellular carcinomas were compared to HCV-ve ones. Statistically significant differences for ploidy values (p < 0.05), percentage of binucleated hepatocytes (p < 0.05) and fraction of mononucleated hepatocytes in the polyploid compartment (p = 0.003) were also found between hepatocellular carcinoma associated only to hepatitis B virus infection ("pure" hepatitis B virus cases) and those associated only to hepatitis C virus infection ("pure" hepatitis C virus cases).

CONCLUSIONS

Hepatocellular carcinoma associated with a previous or actual hepatitis B virus infection shows a peculiar phenotypical appearance, characterized by a trend towards increasing ploidy and reduction of binuclearity.

Numerical chromosome aberrations in hepatocellular carcinoma detected by fluorescence in situ hybridization

AIMS/METHODS

Numerical aberrations of chromosomes 7,8,9,10,12,17,18, X and Y were examined in 38 hepatocellular carcinoma specimens using centromere-specific DNA probes by the fluorescence in situ hybridization method.

RESULTS

Numerical aberrations in more than one of the chromosomes examined were found in 27 of 38 (71%) specimens; 6 of 15 (40%) well-differentiated hepatocellular carcinomas; 15 of 17 (88%) moderately differentiated hepatocellular carcinomas; and all of 6 (100%) poorly differentiated hepatocellular carcinomas. Of 6 early hepatocellular carcinomas, numerical chromosome aberrations were detected in 2. The incidence of numerical chromosome aberrations was 93.8% in patients with portal vein thromboses and/or intrahepatic metastases, 52.4% without portal vein thromboses and/or intrahepatic metastases (p < 0.05), while 89.5% of patients with a tumor more than 3 cm in diameter and 50.0% with a tumor less than 3 cm in diameter had chromosome aberrations (p < 0.05).

CONCLUSIONS

These results suggest that numerical chromosome aberrations start to occur in the early stage of hepatocellular carcinoma and to accumulate during tumor progression.

Frequent loss in chromosome 8p loci in liver cirrhosis accompanying hepatocellular carcinoma

Most hepatocellular carcinoma (HCC) is preceded by liver cirrhosis, but the genetic changes involved in cirrhosis are not well understood. We therefore studied loss of heterozygosity (LOH) in cirrhotic and neoplastic foci in livers of 14 patients with HCC. The samples, microdissected from paraffin-embedded tissues, were analyzed using a polymerase-chain-reaction-based assay for dinucleotide repeat polymorphisms on 8p. Of the 14 cases, 13 showed constitutional heterozygosity for the microsatellite markers. In 7 (54%) of these 13 informative cases, LOH was detected in the primary HCC and, in these 7 doubly informative (informative and LOH-positive in primary HCC) cases, LOH was found in 16 (70%) of 23 liver cirrhotic foci. The pattern of 8p allelic loss was identical in each doubly informative tumor; however, some of the liver cirrhotic foci harbored an 8p loss identical to that seen in the primary HCC, some harbored a different 8p loss, and some did not harbor any 8p loss. The remaining 6 cases without LOH on 8p in HCC showed no 8p loss in any cirrhotic foci. Presumably HCC could develop from cirrhotic cells harboring 8p loss.

Flow cytometric DNA analysis of cirrhotic liver cells in patients with hepatocellular carcinoma can provide a new prognostic factor

BACKGROUND

DNA flow cytometry of hepatocellular carcinoma (HCC) cells has been investigated in many studies, but, to the best of our knowledge, there are no data on DNA analysis of cirrhotic parenchyma around the HCC. In this study, cell kinetics and ploidy of parenchymal cells around HCC were performed to ascertain if this would predict the possibility of recurrence in the cirrhotic areas.

METHODS

The DNA content of 93 cases of HCC and of cirrhotic liver around the tumor nodules was analyzed by flow cytometry. Ploidy and proliferative index of HCC and cirrhotic liver were compared with macroscopic, histologic, and clinical features of each case and linked with the behavior of these tumors. Survival curves were assessed according to the Kaplan-Meier method. A multivariate analysis based on Cox proportional hazards regression model was performed on cases of diploid cirrhosis cells in which the S-phase fraction was evaluable.

RESULTS

The univariate analysis of survival suggested significant roles for age, number of intrahepatic nodules, Edmondson-Steiner's classification, portal invasion, vascular invasion, presence of necrosis, hepatitis B surface antigen, alpha-feto-protein, Child's score, ploidy, and S-phase fraction of HCC cells. The DNA analysis of the cirrhotic cells showed that polyploidy was dramatically reduced in patients with HCC, compared with normal hepatocytes, and aneuploid clones were present among diploid cells. High S-phase fraction of cirrhotic cells and Child-Pugh classification were the strongest independent parameters affecting the tumor behavior in this study.

CONCLUSIONS

The results of this study suggest that S-phase fraction of cirrhotic liver parenchyma may be employed as a new parameter in the prognostic evaluation of HCC patients.

DNA image analysis study of lesions of the gallbladder and biliary system

DNA ploidy analysis of 22 lesions arising from the intrahepatic and extrahepatic biliary systems and gallbladder was performed on Feulgen-stained 5-microns sections from archival paraffin-embedded tissue on an image analyzer (CAS-200). The cases included intrahepatic cholangiocarcinoma (n = 6), extrahepatic bile duct carcinoma (n = 5), carcinoma of the gallbladder (n = 11), and appropriate controls. All malignancies were stage III and IV adenocarcinomas with the exception of 1 stage II moderately differentiated gallbladder adenocarcinoma. No correlation with ploidy and stage could be made, most likely because of the advanced stage of the tumors at the time of presentation. When DNA ploidy was compared with the grade of tumor, the 3 well-differentiated adenocarcinomas (2 cholangiocarcinomas, 1 bile duct carcinoma) were predominantly diploid; however, diploid peaks were also found in moderately differentiated adenocarcinomas of all 3 sites and in a poorly differentiated adenocarcinoma of the extrahepatic bile ducts. Finally, 15 of 22 (68%) of cases showed only aneuploid populations. Multiple populations were observed in 19 of the 22 cases; this finding may reflect intratumoral heterogeneity and correlate with the advanced stage and aggressive nature of malignancies of the gallbladder and biliary system.

Report of a complex karyotype in recurrent metastatic fibrolamellar hepatocellular carcinoma and a review of hepatocellular carcinoma cytogenetics

Metastatic fibrolamellar hepatocellular carcinoma (HCC) was detected in the abdominal lymph nodes of an adolescent male after resection of the primary tumor. No dividing cells were isolated from attempted cytogenetic studies of the primary tumor. However, cytogenetic analysis of lymph node metastases detected 9 and 12 months after partial hepatectomy revealed abnormal hypertriploid karyotypes, with a suggestion of clonal evolution: 62-92 < 3n >,XX, -Y, +3, +6, +6, +7, +7, +8, +10, +13, +15, +16, +20, -21, -22, +mar1 x 2, +mar[cp6]/46,XY[8] and 78 < 3n >,XX, -Y,der(1)t(1;1)(p36.1;q21), +4, +6, +6, +7, +7,i(8)(q10), +10, +15, +20, -21, -22, +mar1 x 2, +mar2[3]/46, XY[17], respectively. Karyotypes of this variant of HCC have not been reported previously. The cytogenetics of HCC are reviewed.

Cytogenetic analyses of hepatocellular carcinoma by in situ hybridization with a chromosome-specific DNA probe

BACKGROUND

Numerical chromosome analysis has been established in solid tumors by using in situ hybridization (ISH) with a chromosome-specific probe. We analyzed human hepatocellular carcinoma (HCC) by ISH for chromosome 17 and investigated the correlation of its copy number with histologic malignancy, proliferative activity, p53 mutation, and DNA ploidy.

METHODS

Chromosome 17 was hybridized with a pericentromere-specific DNA probe directly on the tumor cells isolated from paraffin blocks of 25 surgically resected HCCs. Proliferative activity was measured by Ki-67 immunohistochemistry, p53 mutation was analyzed by p53 immunohistochemistry, and DNA ploidy was estimated by cytofluorometry.

RESULTS

Forty-four percent of the 25 HCCs showed numerical abnormality of chromosome 17. Many disomic cases had a less malignant histology, whereas many polysomic cases had a more malignant histology. The Ki-67 positive index of polysomic cases was higher than that of disomic cases. In 22 cases (88.0%), the copy number of chromosome 17 was well matched with DNA ploidy. However, the numerical abnormality of chromosome 17 did not show a significant correlation with p53 mutation. Two of four HCCs that showed histologic heterogeneity were also heterogenous on ploidy pattern and the copy number of chromosome 17. Conversely, there was one case in which only ISH could demonstrate heterogeneity, although the other features exhibited homogeneity.

CONCLUSIONS

Numerical chromosome abnormalities correlated with the increase of histologic malignancy proliferative activity, and DNA ploidy. Moreover, ISH analysis was useful in assessing the intratumoral heterogeneity in HCC, especially when current methods failed to detect it. Thus, ISH provides information on important biologic features, such as malignant potential and intratumoral heterogeneity, in HCC.

[DNA content of the tumor cell. A new prognostic parameter in hepatocellular carcinoma?]

Hepatocellular carcinoma is a heterogeneous disease with considerable differences in malignant behaviour. Some relevant factors for prognosis are known. In this study we analysed DNA ploidy as a potential prognostic parameter. With DNA image cytometry we were able to differentiate between diploid, hypotriploid, triploid, hypertriploid, tetraploid and aneuploid tumours. The best prognosis was for patients with diploid, hypotriploid and tetraploid tumours with a median survival time of 41 months in contrast to 3 months for patients with triploid, hypertriploid or aneuploid tumours. There was a strong correlation between histomorphological parameters and the DNA content. The DNA content of tumour cells may be considerable clinical relevance in hepatocellular carcinoma regarding the decision as to whether or not to perform a resection. In patients with prognostically unfavorable parameters adjuvant oncological therapy may improve the prognosis.

DNA flow cytometry in patients undergoing liver transplantation for hepatocellular carcinoma

The purpose of the study was to analyse patterns of DNA content in hepatocellular carcinomas (HCC) submitted to orthotopic liver transplantation (OLT). Paraffin-embedded archival material from 15 patients (ten men, five women, mean age 51 +/- 1.78 years) transplanted in St-Roch Hospital between 1988 and 1991 was available for laboratory evaluation by flow cytometry. Five out of 15 were incidental HCC. The analysis was performed by a FACSscan flow cytometer coupled to a Hewlett-Packard computer. The cellular DNA content was defined as diploid or aneuploid in the presence of a single (DNA index of 1) or two distinct (DNA index different from 1) Gzero/G1 peaks, respectively. All incidental HCC (five patients) were diploid, the tumour size was 1.2 +/- 0.2 cm, the number of nodules was 1.4 +/- 0.24 and the mortality rate was 40%. No death in the incidental HCC group was related to neoplastic recurrence. In the remaining ten patients transplanted for HCC, we observed 50% diploid tumours, the tumour size was 5.2 +/- 1.55 cm and the number of nodules was 2.7 +/- 0.56. In this group six patients died of neoplastic recurrence (two were diploid and four aneuploid). The diameter of the neoplasm in diploid patients who died of neoplastic recurrence was over 5 cm and the number of nodules was over three. Moreover, in aneuploid patients who died of neoplastic recurrence, the diameter of the neoplasm was less than 5 cm in three cases and the number of nodules was less than three in two patients. This study indicates that incidental HCC may be a less aggressive malignancy and may have a better prognosis. In this group, no patient recurred after OLT and all tumours were diploid. Aneuploidy, tumour size (> 5 cm) and number of lesions (> 3) are prognostic indicators for neoplastic recurrence in patients transplanted for hepatocellular carcinoma.

Study of repeated arterial infusion chemotherapy with a subcutaneously implanted reservoir for advanced hepatocellular carcinoma

We performed repeated arterial infusion chemotherapy (RAIC) in 114 advanced hepatocellular carcinoma (HCC) patients, using a subcutaneous reservoir implanted under ultrasonic guidance. In 60 patients, this was the initial therapy for the primary tumor and the other 54 patients being treated for recurrent tumor. One hundred and seventy-one patients with advanced HCC who had been treated by transcatheter arterial embolization (TAE) or single bolus arterial infusion chemotherapy before RAIC was available served as historical controls. In 97 patients, anticancer agents (4'-epidoxorubicin or acurarubicin) and Lipiodol emulsion were used, and in 17, anticancer agents alone were given. The response rates were 39.2% in the Lipiodol group and 17.6% in the non-Lipiodol group. The dose of Lipiodol and the degree of liver invasion were the most important factors influencing the response rate. The 1-, 2-, and 3-year survival rates were 55.0%, 30.9%, and 21.2%, respectively. The long-termsurvival was compared in relation to Child's classification and the presence or absence of portal vein tumor thrombosis (PVTT). In non-PVTT patients, the results of initial therapy and therapy for recurrence were similar, but recurrent Child's C patients showed a poorer prognosis. In PVTT patients, initial therapy had a better prognosis than treatment for recurrence, but initial Child's C patients had a poor long-termprognosis. During the observation period, no severe complications were encountered, but in Child's C patients, hepatic function sometimes deteriorated. Compared with the results in the 171 controls, RAIC was more useful for advanced HCC as initial therapy, and it was also beneficial for the treatment of recurrence after TAE.

Flow cytometric analysis of DNA heterogeneity in superficial carcinoma of the esophagus

BACKGROUND

There are few studies of flow cytometric analysis for DNA heterogeneity of patients with superficial carcinoma of the esophagus limited to the epithelium or superficially invading the lamina propria or submucosa.

METHODS

Flow cytometric analysis of cellular DNA content was performed on superficial carcinomas of the esophagus using paraffin embedded blocks of the surgically resected specimens from 56 patients. To evaluate the intratumoral DNA heterogeneity, a total of 141 samples of the 56 tumors were analyzed, depending upon the tumor size.

RESULTS

One or two of the samples was available from 18 of 19 patients with tumors 2 cm or less in greatest dimension, whereas more than three of the samples were available from 22 of 37 patients with tumors 2.1 cm or greater in dimension (P < 0.003). Of 56 tumors, 40 (71.4%) exhibited DNA aneuploidy; DNA heterogeneity was found in 26 tumors (46.4%). The remaining 16 tumors exhibited DNA diploidy. Two of the five tumors that were limited to the epithelium had DNA heterogeneity. The mean dimension of the tumors with DNA heterogeneity was significantly greater (5.8 +/- 2.8 cm) than those exhibiting DNA diploidy (2.3 +/- 1.1 cm) and DNA aneuploidy without heterogeneity (2.9 +/- 2.4 cm). Recurrences after esophagectomy were detected in 6 of the 56 patients; the DNA ploidy pattern of these six patients exhibited DNA heterogeneity.

CONCLUSION

The incidence of DNA heterogeneity increases as tumor size increases and is associated with an increased risk of tumor recurrence after esophagectomy in patients with superficial carcinoma of the esophagus.

Intratumoral DNA heterogeneity of small hepatocellular carcinoma

BACKGROUND

Intratumoral DNA heterogeneity provides important information regarding biologic and clinical behavior. The purpose of this study was to evaluate the incidence of DNA heterogeneity in small hepatocellular carcinoma (HCC) nodules.

METHODS

The DNA content of 28 surgically resected small HCC nodules (< or = 3.0 cm) was measured using flow cytometry of fresh or frozen samples taken from different parts of each nodule with reference to the macroscopic features.

RESULTS

Of the 28 small HCC nodules, 14 (50.0%) had only DNA diploid stemline characteristics. Five nodules (17.9%) manifested DNA diploid and DNA aneuploidy within the same tumor. Of the remaining nine nodules (32.1%) that showed only DNA aneuploidy, two contained tumor tissues with apparently different DNA content. Thus, DNA heterogeneity was found in 7 (25.0%) of 28 nodules. DNA heterogeneity correlated well with macroscopic histologic features. All four early HCC were composed of only DNA diploid cells, whereas three of six nodule-in-nodule lesions were composed of DNA heterogeneous cells, in which the inner obviously cancerous nodule showed DNA aneuploidy and the outer well differentiated HCC portion demonstrated DNA diploid. Four of 18 overt HCC nodules showed DNA heterogeneity; 2 of these 4 nodules showed both diploid and aneuploid peaks, and the other 2 two showed different aneuploid peaks within the same nodule.

CONCLUSIONS

DNA heterogeneity correlating with macroscopic features is found frequently even in small HCC nodules. Therefore, multiple sampling based on macroscopic features is required for the accurate assessment of DNA ploidy, particularly when the information about DNA ploidy is used as a prognostic indicator.

Effects of preoperative chemotherapy on DNA ploidy patterns, cell cycle, and histological findings in gastric and colonic cancer patients

The effects of preoperative chemotherapy on gastric and colonic cancers have yet to be evaluated fully. In this study, its effects were assessed by studying DNA ploidy patterns, cell cycles, and histological findings in such patients. Thirty-nine patients with gastric or colonic cancer were given preoperative chemotherapy with UFT (an admixture of tegafur and uracil). Biopsy specimens for analysis were obtained before chemotherapy through a gastroscope or colonoscope and after chemotherapy from resected tumors. The DNA ploidy patterns and cell cycles were evaluated using a flow cytometer and the tissues were examined histologically. The DNA ploidy pattern was diploid (D) in 12 gastric and 13 colonic cancer patients and aneuploid (A) in 10 and 4 patients, respectively. After chemotherapy, the pattern changed in nine gastric (A-->D: 7, D-->A: 2) and six colonic cancer patients (A-->D: 3, D-->A: 3) and was unchanged in the remaining patients. Cell cyclic analysis showed decreased G1- and increased S-phase fractions in 10 of 12 patients with gastric and 6 of 10 patients with colonic cancer. Histologically, decreased tumor cellularity, increased fibrosis, and/or cytological changes were observed in both cancers after chemotherapy. Gastric and colonic cancers in which the DNA ploidy pattern changed from aneuploid to diploid, G1- decreased and S-phase increased, and/or histological changes were observed, were considered to have responded to preoperative UFT administration.

Diagnostic and prognostic value of DNA ploidy and cell nuclearity in ultrasound-guided liver biopsies

BACKGROUND

Focal nodule lesions in patients with cirrhotic livers may be visualized by using imaging techniques; however, the diagnostic and prognostic judgment of biopsies from borderline lesions may be difficult using conventional histologic criteria.

METHODS

The diagnostic and prognostic value of DNA ploidy analysis determined by image cytometry of Feulgen-stained isolated hepatocytes was investigated in ultrasound-guided biopsies from 50 nodular lesions found in patients with cirrhotic livers (39 hepatocellular carcinomas [HCCs] and 11 macroregenerative nodules) and from 10 patients with livers affected by viral chronic hepatitis. Of the 11 macroregenerative nodules, 7 presented a subsequent neoplastic behavior. Specimens from the morphologically normal livers of five patients who underwent liver surgery served as control tissues. Image cytometry was performed on Feulgen-stained cytologic preparations, obtained by enzymatic digestion of formalin fixed biopsies. The DNA ploidy of the main stem line and the distribution of mononucleated and binucleated hepatocytes (nuclearity) were compared using histologic diagnosis, Edmondson's grade, tumor size, and patient follow-up.

RESULTS

The main stem line was peridiploid in all benign specimens and in 31 clinically confirmed HCCs, peritetraploid in 11 HCCs, perioctaploid in 1 HCC, and aneuploid in 3 HCCs. The fraction of mononucleated polyploid hepatocytes was found to be the best diagnostic parameter in euploid HCCs and was significantly correlated with the Edmondson grade and the nodular size. Survival information was available for 43 patients, with a median observation period of 350 days. A DNA ploidy value of the main stem line greater than 3c was an important determinant of survival as a single parameter and in association with histologic grade and greatest dimension of tumor.

CONCLUSIONS

This study suggests that the ploidy distribution analysis of mononucleated and binucleated hepatocytes can provide valuable information for making correct diagnoses and for predicting survival outcome for patients with HCCs.

DNA ploidy of fibrolamellar hepatocellular carcinoma by image analysis

Twelve cases of fibrolamellar hepatocellular carcinoma (FLC) were evaluated for DNA ploidy by means of image analysis of Feulgen-stained tissue sections. All of the tumors showed a nondiploid DNA distribution (six aneuploid and six tetraploid); no diploid pattern was found. The nuclear area of the tumors (53.8 microns 2 +/- 18.0; mean +/- standard deviation) was significantly larger than that of the surrounding noncancerous livers (33.2 +/- 4.7; P < .0001). These findings suggest that DNA content in fibrolamellar carcinoma (FLC) is not directly related to the clinical behavior and that other factors may be responsible for the better prognosis of this variant of HCC.

Prospective flow cytometric DNA analysis of hepatocellular carcinoma specimens collected by ultrasound-guided fine needle aspiration

BACKGROUND

The survival of 52 patients with hepatocellular carcinoma (HCC) seen during the last 4 years was analyzed prospectively on the basis of disease stage and nuclear DNA content.

METHODS

Ploidy was measured by flow cytometry (FCM). Cells for cytologic diagnosis and FCM were collected by ultrasound-guided fine needle aspiration.

RESULTS

DNA aneuploidy, which was detected in 62% of the patients, did not correlate with clinicopathologic features, except in the sonographic aspect (P = 0.03). However, ploidy correlated significantly with survival; the survival times for patients with an aneuploid DNA index were significantly shorter than for those with a diploid index (P = 0.02). In a Cox multivariate analysis, DNA content was prognostically significant, as were the grade of cirrhosis severity and the echographic aspect.

CONCLUSIONS

In addition to the clinicopathologic features observed, FCM DNA analysis of ultrasound-guided fine needle aspirates from HCC is a simple and valid method for estimating a prognosis of these patients.

The significance of atypia and histologic malignancy in pilocytic astrocytoma of the cerebellum: a clinicopathologic and flow cytometric study

Biologically malignant pilocytic astrocytomas are rare. Precise morphologic criteria permitting their identification and clinically meaningful distinction from more ordinary pilocytic astrocytomas have not been developed. The histologic grading schemes applied to fibrillary astrocytomas--ones based on nuclear atypia, increased cellularity, mitotic activity, endothelial proliferation, and necrosis--are thought not to correlate with prognosis in pilocytic astrocytomas. Nonetheless, these features were systematically sought in 107 cerebellar pilocytic astrocytomas, four of which were histologically malignant. The clinical, morphologic, and flow cytometric features of these cases were studied. The incidence of histologic malignancy occurring spontaneously in otherwise typical pilocytic astrocytomas was 0.9%; that occurring after radiation was 1.8%. The four histologically malignant tumors occurred in two males and two females, ages 6 to 18 years. All showed increased mitotic activity (three to five mitoses per high-power microscopic field [250x]). Endothelial proliferation and necrosis were present in three and two cases each. DNA ploidy analysis showed the spontaneously occurring malignant-appearing tumors to be aneuploid, whereas both previously radiated tumors were tetraploid; 5% to 11% of cells were in S phase. The appearance of histologic malignancy in pilocytic astrocytoma is rare and less reliably correlated with prognosis than in patients with fibrillary astrocytomas. Essential features of such tumors include a high mitotic index and perhaps a high percentage of cells in S phase.

Aggressive medulloblastoma with high-level N-myc amplification

A 27-year-old man was treated for an aggressive cerebellar medulloblastoma that, at operation, exhibited dural invasion. Six months after gross total resection and radiation therapy, a "surgical metastasis" developed in the lower portion of the surgical scar. The tumor grew rapidly down into the right side of his neck. Chemotherapy failed, and he subsequently died. Cytogenetic and molecular genetic studies revealed multiple numeric and structural chromosome abnormalities, including an abnormal chromosome 17p arm, more than 100-fold N-myc amplification, a rearranged c-myc gene, and a 16-base pair deletion involving exon 7 of the p53 gene. We postulate that these genetic features may have contributed to the aggressive behavior of the tumor.