Search PubMed⌕ Search

Biomedical subjects

Nobukazu Yuki

Publications and source records attributed to Nobukazu Yuki.

8 recordsLinked to original sources

Squamous cell carcinoma as a rare entity of primary liver tumor with grave prognosis.

The development of primary squamous cell carcinoma (SCC) of the liver has only rarely been reported in association with pre-existing hepatic cysts and biliary tract diseases. This report describes an unusual case of SCC originating in a cirrhotic liver. A 63-year-old male alcoholic was incidentally found to have a 6-cm liver tumor which showed mixed echogenic by sonography and a low-density area with rim enhancement by computed tomography. Tumor biopsy led to a diagnosis of SCC with a sarcomatoid change. The tumor showed fatal rapid growth accompanied by abdominal pain. Transcatheter arterial embolization and chemotherapy were not effective, and the tumor increased to 13cm in diameter over an 8-month period. A post-mortem search revealed no alternative primary tumor site other than liver. Review of the literature shows that abdominal pain is a chief symptom of primary liver SCC. Only three of the nine patients treated with hepatic resection survived without recurrence during 8 months to 4 years of follow-up. We propose that SCC with a grave prognosis should be considered as a rare entity of primary liver tumor even in cirrhotic patients.

Journal Article↗

Significance of liver negative-strand HCV RNA quantitation in chronic hepatitis C.

BACKGROUND/AIMS: Liver negative-strand hepatitis C virus (HCV) RNA is the most direct indicator of active viral replication but has only been examined in a few semiquantitative studies. METHODS: Positive- and negative-strand HCV RNA in the right (R) and left (L) liver lobes was quantified by rTth-based strand-specific real-time polymerase chain reaction for 48 chronic hepatitis C patients. RESULTS: Close correlations between lobes were seen for positive- and negative-strand amounts (r = 0.950; P < 0.001 and r = 0.920; P < 0.001, respectively). The ratio of negative to positive strands (median, 0.14 for R and 0.13 for L) varied by 2 log directly in relation to HCV replication assessed by liver negative strands but had no relation to liver positive strands and circulating HCV. Only negative-strand quantitation was inversely correlated with age (r = -0.322; P = 0.026 for R and r = -0.340; P = 0.018 for L), while liver tissues with hepatitis B virus DNA contained larger amounts of each strand. In 27 patients treated with enhanced interferon monotherapy, the amounts of liver negative strands (<4 log copies/100 ng RNA) were the only independent predictor of a sustained virologic response. CONCLUSIONS: Negative-strand quantitation is uniform in the liver and bears distinct relevance to the disease.

Adult↗

Long-term clinical and virological outcomes of chronic hepatitis C after successful interferon therapy.

Clinical relevance of occult hepatitis C virus (HCV) and/or hepatitis B virus (HBV) infection(s) remains uncertain years after interferon (IFN) therapy for chronic hepatitis C. By 1993, 38 sustained virological responders (SVRs) showing HCV RNA clearance at 6 months post-treatment and 37 biochemical responders (BRs) with end-of-treatment alanine aminotransferase (ALT) normalization and subsequent 6-month stabilization within 2 x the upper limit of normal (ULN) were enrolled. They were monitored for 4.4-12 years (median 6.8), then 15 SVRs and 15 BRs underwent paired liver biopsies. Biopsy samples were tested for positive and negative HCV RNA strands, and HBV DNA surface and X sequences. All SVRs showed sustained serum HCV RNA clearance during follow-up, but hepatocellular carcinoma (HCC) developed in 4 (11%) SVRs. On paired liver biopsies, histological improvement was significant, but mild inflammation persisted in 87% of SVRs. Nonetheless, no HCV RNA sequence was amplified from liver tissues, and HBV DNA sequences were found in only one SVR. As for BRs, biochemical flare-up of >2 x ULN occurred at a 5-year risk of 41% (95% CI 24.7-56.4). The event was unpredictable but controllable by retreatment in 70%. Liver tissues after follow-up contained positive and negative HCV RNA strands, but no HBV DNA sequence was amplified. These results suggest that SVRs, albeit free of occult HCV and/or HBV infection(s) over a decade, retain mild liver inflammation and the risk of HCC. Occult HBV was also shown uninvolved in flare-up during follow-up of BRs.

Adult↗

Circulating soluble Fas levels in patients with hepatitis C virus infection and interferon therapy.

BACKGROUND: The clinical relevance of the circulating soluble form of the Fas-Receptor (sFas) was investigated in patients with hepatitis C receiving type 1 interferon (IFN) therapy. METHODS: sFas was quantified by enzyme-linked immunosorbent assay in 66 hepatitis C virus (HCV) carriers and 30 HCV-naive or previously infected controls. The levels were then monitored during enhanced treatment with type 1 IFNs in 15 chronic hepatitis C patients. RESULTS: The HCV carriers had high levels of sFas compared with controls (3.8+/-1.3 vs 2.7+/-0.8 ng/ml; P<0.001). sFas levels in patients with chronic HCV infection were directly related to serum alanine aminotransferase levels (r=0.440; P<0.001) and the histological grade (r=0.403; P=0.019). Among necroinflammatory reactions, only piecemeal necrosis showed a correlation with sFas levels (r=0.556; P=0.001). Pretreatment sFas levels, however, were not predictive of therapeutic outcomes. A sustained virological response to enhanced IFN therapy showed a relation to only the pretreatment HCV load. Interestingly, circulating sFas was upregulated when IFN-beta was administered at short intervals (3 MU/every 12 h). This upregulation was accompanied by parallel aminotransferase elevation, which was observed regardless of a virological response. CONCLUSIONS: sFas elevation, in parallel with the severity of liver injury, suggests the possible upregulation of hepatic Fas expression and the Fas-mediated pathway in both HCV- and type 1 IFN-induced liver injury. The essential function of sFas to protect hepatocytes against Fas-mediated liver injury was not evident in these clinical settings.

Adult↗

Histological improvement of chronic liver disease after spontaneous serum hepatitis C virus clearance.

The long-term histological and virological outcomes of spontaneous circulating hepatitis C virus (HCV) clearance were studied in chronic liver disease. Between 1979 and 1984, three patients underwent laparoscopy for chronic non-A, non-B liver disease, and two were found to have cirrhosis and one with chronic active hepatitis. After HCV assays became available in 1990, they were positive persistently for HCV antibody without serum HCV RNA. Reductions of antibody levels to HCV core and/or nonstructural proteins were observed, and liver biopsies were undertaken between 1995 and 2000. Liver biopsies at 11-19 years after laparoscopy disclosed marked alleviation of liver inflammation and fibrosis in each case although a low grade of inflammation remained. The two patients with cirrhosis no longer showed histological features of cirrhosis, and the poor liver function in one patient had been ameliorated. Liver specimens from two patients were subjected to polymerase chain reaction to detect positive and negative HCV RNA strands and hepatitis B virus DNA. Only the positive HCV RNA strand was detected for one patient who had previously cirrhosis. Liver specimens were examined from another six nonviremic HCV-seropositive individuals without chronic liver disease. Five patients displayed low-grade liver inflammation without evident fibrosis, but none had any viral genome in the liver. These findings suggest that spontaneous circulating HCV clearance in chronic liver disease confers favorable liver histological outcome, although occult HCV infection persists. J. Med. Virol. 69:41-49, 2003.

Female↗

Long-term histologic and virologic outcomes of acute self-limited hepatitis B.

The long-term impact of acute self-limited hepatitis B on the liver is unknown. Fourteen patients were recalled at a median of 4.2 years (range, 1.8-9.5 years) after the onset of acute hepatitis B. All showed clinical and serologic recovery with circulating hepatitis B surface antigen (HBsAg) clearance. Antibody to HBsAg (anti-HBs) had developed in 12 patients. Nine underwent liver biopsies at a median of 7.2 years, and histologic findings were evaluated using Ishak scores. Serum samples and frozen liver tissue were subjected to real-time detection polymerase chain reaction (PCR) to quantify the surface and X regions of the hepatitis B virus (HBV) genome and qualitative PCR to detect the covalently closed circular (ccc) HBV DNA replicative intermediate. Three patients had low levels of circulating HBV DNA up to 8.9 years after the onset, whereas both HBV DNA surface and X regions were found in the liver of all 9 patients examined, including 7 negative for serum HBV DNA. Liver viral loads assessed by the 2 regions showed a significant correlation (r = 0.946; P =.008), and all patients tested positive for ccc HBV DNA. Liver fibrosis and mild inflammation persisted in 8 patients. The fibrosis stage had relation to peak serum HBV DNA in the acute phase (P =.046) but not to liver viral loads in the late convalescent phase. In conclusion, occult HBV infection persists in the liver and is accompanied by abnormal liver histology for a decade after complete clinical recovery from acute self-limited hepatitis B.

Acute Disease↗