A prospective, controlled, nonrandomized study on prophylactic parenteral dichloromethylene bisphosphonate (clodronate) in multiple-myeloma

Bone resorption by osteoclasts causes neoplastic bone disease, which is a significant cause of death in multiple myeloma (MM). Counteracting bone resorption with prophylactic bisphosphonates has delayed bane disease, and this is expected to improve survival. Between January, 1987 and March, 1990, 341 evaluable previously untreated, consecutive patients with MM entered a prospective, multicenter study in which cytostatic therapy was randomized. The first 148 patients recruited were not planned for prophylaxis and the following 193 were scheduled to receive parenteral, prophylactic clodronate. Clodronate was administered at a dose of 600-1000 mg/4-6 weeks and was started at diagnosis and continued throughout survival time. Data on clodronate prophylaxis were evaluated on both an intention-to-treat and a compliance analysis basis. The rate of response and the duration of response were independent of clodronate prophylaxis. Progression of skeletal disease occurred less often in patients who received the drug than in those who were not given prophylaxis (50.5 vs 34.8%; p<.02 by compliance analysis). Survival was longer for patients on clodronate prophylaxis than for those who were not planned for (p<.02 by intention to-treat-analysis) or for those who did not receive clodronate prophylaxis (p<.009 by compliance analysis). Local pain associated with i.m. administration was the only significant side effect of clodronate. Parenteral clodronate prophylaxis prolongs survival in MM, probably because it allows better control of bone disease and reduces deaths related to it.

A randomized trial of prolonged high dose of interferon plus ribavirin for hepatitis C patients nonresponders to interferon alone

Retreatment of chronic hepatitis C patients nonresponders to interferon (IFN) alone with the standard dose of IFN [3 million units (MU) thrice weekly (TIW)] plus ribavirin for 24 weeks has yielded low sustained virological response (SVR), averaging 8%. The aim of the present, open-labelled, randomized study was to evaluate the efficacy of IFN induction therapy followed by prolonged high dose of IFN plus ribavirin in nonresponders. One hundred and fifty-one patients were randomized to receive 5 MU daily of IFN alfa-2b (group 1, n = 73) or 5 MU TIW of IFN alfa 2b (group 2, n = 78) for 4 weeks followed by IFN (5 MU TIW) plus ribavirin (1000/1200 mg/daily) for 48 weeks in both groups. In an intention-to-treat analysis, the sustained virological response (SVR) at 24-week follow-up was 33 and 23% for group 1 and 2, respectively (P = 0.17). The overall SVR was 52 and 18% in patients with genotype 2/3 and 1/4, respectively. Among genotype 1/4 patients the SVR was 29 and 11% for age younger or older than 40 years. Compared with genotype 2/3 patients, the risk (95% confidence interval) of nonresponse to retreatment was 3.0-fold (1.17-8.0) in younger genotype 1/4 patients and 8.4-fold (3.0-23.29) in older genotype 1/4 patients. In conclusion these results suggest that retreatment with a reinforced regimen should be focused in nonresponder genotype 2/3 patients and younger genotype 1/4 patients, who are most likely to benefit. Induction therapy does not improve SVR.

Efficacy of prolonged 5 million units of interferon in combination with ribavirin for relapser patients with chronic hepatitis C

summary. Retreatment of relapser patients with chronic hepatitis C with the standard dose of interferon (IFN) of 3 million units (MU) thrice weekly (tiw) plus ribavirin for 24 weeks achieves a sustained response in 30 and 73% of patients with genotype 1 and 2 or 3, respectively. The aim of this study was to evaluate the efficacy and safety of IFN alpha-2b induction therapy, followed by prolonged treatment with a high dose of IFN alpha-2b plus ribavirin in relapser patients. A total of 119 patients were randomized to receive IFN alpha-2b 5 MU daily (Group A: 59 patients) or IFN alpha-2b 5 MU tiw (Group B: 60 patients) for 4 weeks followed by IFN (5 MU tiw) and ribavirin (1000-1200 mg/day) for 48 weeks in both groups. The primary end point was hepatitis C virus (HCV)-RNA clearance at week 24 after the end of treatment. A sustained virological response (SVR) was achieved in 68 and 60% of Group A and B patients, respectively (P = 0.37). Logistic regression analysis identified genotype 2 or 3 as the only independent factor associated with response, whereas induction regimen and baseline viraemia levels did not affect the response. The overall SVR was 53 and 72% in patients with genotype 1 or 4 and 2 or 3, respectively. In conclusion, induction IFN therapy does not enhance the SVR to a 48-week combination therapy. Our study suggests that relapsed patients with genotype 1 or 4 may achieve significant response rates of approximately 50%, if retreated with 5 MU tiw IFN plus ribavirin for 48 weeks.

Hepatitis C virus infection and clonal B-cell expansion

The striking association between hepatitis C virus (HCV) infection and the so-called "essential" mixed cryoglobulinemia (MC) has led to the hypothesis that HCV plays a major role in the production of cryoglobulins. Analysis of soluble and cryoprecipitable immune complexes shows that the hepatitis C virion is bound to IgM bearing the WA cross-idiotype (XId). The production of WA XId IgM seems to be the result of chronic stimulation by HCV of a population of WA XId + CD5 + B cells. It is possible that the reactivity of WA XId IgM does not initially include rheumatoid factor (RF) activity, which may be acquired secondarily from mutational events accompanying a probably T-cell independent B cell proliferation. Type II MC is a benign proliferation that progresses to malignancy in a minority of patients. This is consistent with the concept that malignancy progression involves the accumulation of multiple mutations of proto-oncogenes and tumor suppressor genes that are facilitated by chronic antigenic stimulation. The recent demonstration of HCV in hyperplastic reactive lymphoadenopathy and in the neoplastic lymph nodes of patients with MC strengthens the putative role played by HCV in lymphomagenesis. A fuller understanding of the virus-related mechanisms of lymphoproliferation in MC patients would contribute significantly to the development of therapeutic strategies.

Immunohistochemical detection of hepatitis C virus-related proteins in liver tissue

OBJECTIVE

Hepatitis C virus (HCV)-associated antigens (Ags) are hard to detect and poorly defined in liver tissue, and are of uncertain interpretation. The failure of immunohistochemistry in HCV infection may be due to the affinity of specific antisera, the levels of Ags in infected tissues, the labile and unstable expression of antigenic determinants, and the use of fixatives that may alter or destroy viral epitopes. Strategies to optimize all stages of tissue specimen processing have therefore been devised in the liver biopsies of patients with acute and chronic hepatitis, and those with hepatocellular carcinoma (HCC).

METHODS

HCV-Ags were detected with a two-stage indirect immunostaining procedure on unfixed cryostat liver sections from 7 acute and 23 chronic HCV-infected patients, and from 4 patients with HCV-associated HCC. A mixture of monoclonal antibodies directed to structural and non-structural HCV-related proteins were used as the primary reagents.

RESULTS

HCV-Ags in 50-70% of the hepatocytes were found in all seven acute hepatitis patients compared with < or = 20% hepatocytes (P < 0.05) in 10 out of 23 patients (43.5%) with chronic hepatitis. Immunoreactive signals appeared as diffuse or coarse granular deposits in the cytoplasm only. The nuclei were unstainable. No clear membranous pattern was found, although fine granular, submembranous accumulation in distinct areas of the cytoplasm was observed. In acute hepatitis, HCV-Ag positive hepatocytes were distributed in the lobules in direct relation to the areas of necrosis and inflammatory cell accumulation, whereas in chronic hepatitis the immunoreactive cells were not clearly related to the necrotic foci. HCV-Ag immunodeposits were demonstrated in all patients with HCC. The immunoreactive signal in neoplastic cells was primarily located in the cytoplasm and rarely in the nuclei. As compared with the non-neoplastic zones, neoplasia demonstrated a significantly higher specific signal.

CONCLUSIONS

Immunohistology is a powerful tool for the identification of HCV-related proteins in liver tissue. Sensitivity was significantly enhanced by the use of fresh-frozen tissues, which presumably preserve their HCV antigen structure, and by a mixture of monoclonal antibodies directed against HCV-related proteins, possibly on account of the separate access of each probe to different target proteins. The demonstration of HCV infection in hepatocyte cytoplasm indicates that this is the primary site of HCV replication, while its presence in malignant cells suggests that the virus could be substantially involved in the pathogenesis of HCC.