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K Chayama

Publications and source records attributed to K Chayama.

At least 163 records · Page 9Linked to original sources
PubMed1994

[The diagnosis of hepatocellular carcinoma determined by pattern of AFP bands separated by Con A affinity electrophoresis].

We analyzed the Con A affinity of serum AFP in patients with a serum AFP concentration greater than 50ng/ml by antibody affinity electrophoresis and Western blotting to distinguish hepatocellular carcinoma (HCC) from benign chronic liver diseases (CLD). Of 164 patients with HCC, 48 (29.3%) had a single band, while 116 (70.7%) had multiple bands. All but three of 65 patients with cirrhosis had a single band. All but one of 32 patients with chronic hepatitis had a single band. We concluded that multiple AFP bands are diagnosis of HCC. This method is a useful assay for distinguishing HCC from CLD.

Adult↗
PubMed1994

Factors predictive of response to interferon-alpha therapy in hepatitis C virus infection.

To determine the patient-dependent and virus-related factors that may predict sustained response to interferon-alpha therapy, we prospectively evaluated 60 consecutive patients with chronic hepatitis C who received a standardized treatment schedule of interferon-alpha. Twenty-eight patients achieved a long-term sustained remission, 14 patients had temporary responses during treatment but relapsed after completing it and 14 patients did not respond. Four patients dropped out because of severe side effects and were excluded from evaluation of efficacy. Twenty-one variables were chosen as possible predictors of sustained response and were analyzed by means of multivariate analysis. Variables related to the hepatitis C virus included genotype and concentration in serum before treatment. The former was determined by means of the polymerase chain reaction with genotype-specific primers for genotypes PT, K1, K2a and K2b, which were deduced from nonstructural region 5 of the hepatitis C virus genome. The latter was measured with a competitive polymerase chain reaction technique. Three variables were statistically significant (p < 0.05) on univariate analysis: viral genotype, pretreatment level of viremia and Knodell's fibrosis score. In multivariate analysis viral genotype and Knodell's fibrosis score were correlated independently with a sustained response (p < 0.05 for both). Incidence of sustained response was 40% and 91% in patients with genotypes K1 and K2a, respectively. We conclude that with the treatment schedule used, viral genotype was the most useful predictor of a sustained response to treatment with interferon-alpha.

Adult↗
PubMed1993

Risk factors for tumor recurrence and prognosis after curative resection of hepatocellular carcinoma.

METHODS: Eighty-three patients with hepatocellular carcinoma (HCC) were treated with curative surgical resection during the past 8 years. RESULTS: No operative deaths occurred. The cumulative recurrence rates after resection at the ends of years 1, 2, and 3 were 37.0%, 57.1%, and 71.6%, respectively. After adjusting the imbalance in clinical factors among patients by using a Cox proportional-hazards model, it was shown that multiplicity, histologic classification, and absence of antibody to hepatitis C virus were associated significantly with recurrence after resection. The size of the tumor did not affect the incidence of recurrence. Thirty-eight of 41 patients with intrahepatic tumor recurrence had undergone at least one of the following three therapies against HCC: surgical reresection, percutaneous ethanol injection (PEI), and transcatheter arterial embolization (TAE). The most significant factor affecting the survival time of patients with tumor recurrence was the total number of tumor nodules at the time of recurrence. Although surgery and PEI were thought to be more effective treatments than TAE in prolonging life, multivariate analysis showed that they were not significant factors of survival time because choices in the method of treatment were correlated closely with the number of cancer nodules. A 65.3% 5-year survival rate from the time of first surgery was accomplished through vigorous therapy when tumors recurred. CONCLUSION: In conclusion, despite the high recurrence rate after resection of HCC, the use of multiple therapies can achieve increased survival rates.

Adult↗
PubMed1993

Effect of lymphoblastoid alfa-interferon in patients with chronic hepatitis C having different genotypic subtype of hepatitis C virus.

Five subtypes of hepatitis C virus (Pt[I], K1[II], K2a[III], K2b[IV] and Tr[V]) have been suggested based on the nucleotide sequence of the non-structural five region. To assess the susceptibility of each subtype to interferon therapy, we developed a one-step method which allows quick determination of subtype using polymerase chain reaction with a mixed primer set deduced from the sequence of each subtype. We were able to determine the subtype of 69 of 80 (86.3%) Japanese patients who received natural alfa-interferon treatment. The incidence of each subtype was K1: 53 (76.8%), K2a: 14 (20.3%), K2b: 3 (4.3%) and Tr: 1 (1.4%). Interferon was administered to these patients and found to be effective in 28 of 51 (54.9%) patients with K1 subtype and in 16 of 18 (88.9%) patients with other subtypes (P < 0.01). These data show that K1 is a major subtype in Japan and relatively resistant to interferon treatment.

Adult↗
PubMed1993

A multivariate analysis of risk factors for hepatocellular carcinogenesis: a prospective observation of 795 patients with viral and alcoholic cirrhosis.

To elucidate the appearance rates of hepatocellular carcinoma in cirrhosis and to assess the risk factors for hepatocellular carcinogenesis, we prospectively studied 795 consecutive patients with viral or alcoholic cirrhosis for 2 to 17 yr (median of 5.8 yr). During the observation period, hepatocellular carcinoma developed in 221 patients. Cumulative appearance rates of hepatocellular carcinoma were 19.4%, 44.3% and 58.2% at the end of the fifth, tenth and fifteenth years, respectively. When classified by the type of hepatitis virus infection, the appearance rates of hepatocellular carcinoma in 180 patients with only HBsAg and in 349 patients with only antibodies to hepatitis C virus were 14.2% and 21.5% at the fifth yr, 27.2% and 53.2% at the tenth yr and 27.2% and 75.2% at the fifteenth yr, respectively. Cox proportional hazard model identified that alpha-fetoprotein levels (p = 0.00001), age (p = 0.00067), positive hepatitis C virus antibodies (p = 0.00135), total alcohol intake (p = 0.00455) and indocyanine green retention rate (p = 0.04491) were independently associated with the appearance rates of hepatocellular carcinoma. Whereas age and indocyanine green retention rate were independent predictors for the appearance rate of liver tumor in the subgroup of HBsAg-positive patients, alpha-fetoprotein levels, age and past alcohol consumption were independent predictors in the group of hepatitis C virus antibody-positive patients. These epidemiological results suggest that some differences exist in the activity and modes of cancer promotion between hepatitis B virus infection and hepatitis C virus infection.

Adult↗
PubMed1993

Diagnosis and follow-up of small hepatocellular carcinoma with selective intraarterial digital subtraction angiography.

To clarify the angiographic features of small hepatocellular carcinoma, we performed digital subtraction angiography in 91 patients with hepatocellular carcinomas of 2 cm or less. Repeated digital subtraction angiography studies were performed in 25 patients whose first angiograms showed no tumor staining. Digital subtraction angiography showed hypervascular tumor staining in only 51 patients (56.0%). We found that the smaller a tumor nodule was, the lower the detection rate of tumor stain on digital subtraction angiography. The detection rate of hypervascularity was closely correlated with the grading of histological differentiation of the tumors: well-differentiated hepatocellular carcinomas more often showed negative tumor staining. Repeated digital subtraction angiography studies showed alteration of tumor staining from isovascular to hypervascular in 6 of 6 patients with tumors that became larger than 2 cm and in 12 of 19 patients with tumors that remained 2 cm or smaller. Conversion of vascularity is commonly found in the early stage of small hepatocellular carcinoma, and the process is usually slow, taking approximately 1 yr.

Adult↗
PubMed1992

Alanine aminotransferase and HCV-RNA responses following interferon therapy of HCV-RNA positive chronic hepatitis.

Interferon (IFN) has been shown to be effective for chronic hepatitis C. This study investigated changes of alanine aminotransferase (ALT) and HCV-RNA in chronic hepatitis C patients treated with alpha-IFN. IFN was given to 73 patients with HCV-RNA positive chronic hepatitis C. The pattern of changes in ALT activity after IFN administration was classified into five types. Type 1 was characterized by normalization of ALT (< or = 25 K.U) during IFN administration and sustained normalization after the IFN therapy. Type 2 involved a rebound of ALT after termination of IFN therapy and subsequent normalization. Type 3 had no ALT normalization during IFN administration, with normalization after the completion of the therapy. Type 4 involved transient normalization of ALT level during IFN therapy, with a subsequent reversion to abnormal levels after the termination of IFN therapy. Type 5 showed sustained abnormally high levels of ALT activity both during and after treatment. Twenty four patients (32.9%) had sustained normalization ALT (< or = 25 K.U) after the termination of IFN treatment. The HCV-RNA negative rate at 6 months after IFN therapy in patients with sustained normalization of ALT was 87.5% (21/24).

Adult↗
PubMed1991

Effect of repeated transcatheter arterial embolization on the survival time in patients with hepatocellular carcinoma. An analysis by the Cox proportional hazard model.

One hundred fifty-eight patients with hepatocellular carcinoma (HCC) were treated by transcatheter arterial embolization (TAE) as repeatedly as possible. Survival rates at the end of the first, second, and third year were 76.5%, 54.5%, and 41.1%, respectively. In 142 patients with repeated TAE, a significantly increased number of patients with complete necrosis of tumor was observed after repetition of the therapy. Adjusting the imbalance in prognostic factors among patients by using Cox proportional hazard model, it proved that the best response during the repeated therapy, rather than the first response, was significantly associated with survival period of the patients. Aside from the factor of response to the treatment, tumor size was the worst prognostic factor at the time when diagnosis was made. Other significant factors were portal vein invasion by HCC and bilirubin. The survival period of patients with HCC treated by repeated TAE was, therefore, affected by cancer factors, liver cirrhosis factors, and therapy-responsiveness factors. It is concluded that even if complete necrosis of tumor is not obtained after the first trial, repetition of TAE is an effective measure for prolonging of survival time in patients with HCC.

Adult↗
PubMed1991

Effect of interferon administration on serum hepatitis C virus RNA in patients with chronic hepatitis C.

Hepatitis C virus RNA as detected by reverse transcription and nested polymerase chain reaction was monitored in 16 patients with chronic hepatitis C treated with interferon. Hepatitis C virus RNA became undetectable after 4 to 8 wk of interferon administration in 13 of the 16 patients. During 6 mo of follow-up, 5 of the 13 patients who became negative for hepatitis C virus RNA after interferon administration remained negative, and all five continued to have normal ALT levels. Repeat liver biopsy in these five patients revealed histological improvement. Antibody to hepatitis C virus, which was initially positive in all treated patients, fell to undetectable levels in three of the five patients. In contrast, aminotransferase levels rose again in all eight patients who had become hepatitis C virus RNA negative but had again exhibited hepatitis C virus RNA after completion of therapy. In 16 untreated patients, hepatitis C virus RNA remained detectable. These results indicate that detection of hepatitis C virus RNA may be useful as a marker of viral replication in chronic hepatitis C; they also suggest that interferon should again be administered to patients who become hepatitis C virus RNA negative on treatment but again exhibit this marker of viral replication when treatment is stopped.

Adult↗
PubMed1991

[Clinical features and viral markers in patients with chronic hepatitis positive for both HBs antigen and anti-C-100 antibody].

Among 612 patients with chronic hepatitis type B, 24 patients tested positive for anti-C-100 antibody. Clinical features and viral markers of these 24 patients were studied. Anti-C-100 antibody was detected more often in patients negative for HBe antigen than those positive for this antigen (22/385 vs. 2/227 [P less than 0.01]). HCV RNA, as detected by reverse transcription and nested polymerase chain reaction, was positive in 20 of 22 patients negative for HBe antigen whereas it was detected in only one of two patients positive for HBe antigen. In a patient who seroconverted from HBe antigen to anti-HBe HCV RNA was undetectable in the HBe antigen positive phase and had become detectable after seroconversion. These data indicate that both hepatitis virus (type B and type C) can co-infect in a patient and that type C becomes active after the seroconversion from HBe antigen to anti-HBe.

Adult↗
PubMed1989

[Remission state and five-year survival after transcatheter arterial embolization therapy in patients with hepatocellular carcinoma].

Repeated transcatheter arterial embolization (TAE) therapy was done for 138 cases with hepatocellular carcinoma. Relationship was investigated between long term survival more than 3 years and tumor necrosis rate estimated on radiological images (superselective angiogram and/or computerized tomography) after therapy. Excellent tumor necrosis (radiological disappearance of viable tumor) was attained in 35 out of 138 cases through repeated TAE. When "remission" is defined as excellent tumor necrosis and normal alphafetoprotein value lasting for more than one year, remission state was attained in 17 cases (12.3%). Cumulative three-year survival rate was 37.0%, and 5-year survival was 26.5%. Out of 37 three-year-survivors, only 12 cases (32.4%) experienced remission state in their clinical course. On the other hand, 7 cases (77.7%) of 9 five-year-survivors experienced remission at least one time. Though good tumor necrosis and 3-year survival were achieved by only performing repeated TAE therapy, "remission" state was important and necessary to get 5-year survival.

Aged↗