Hepatitis B reactivation in patients receiving cytotoxic chemotherapy: diagnosis and management

Chronic hepatitis B infection

The management of chronic hepatitis B virus (HBV) infection requires understanding the natural history of the disease as well as the risks, benefits, and limitations of the therapeutic options. This article covers the principles governing when to start antiviral therapy, discusses recent advances using hepatitis B surface antigen quantification to better define various phases of infection, describes the use of HBV core, precore, and viral genotyping as well as host IL28B genotyping to predict response to interferon therapy, and reports on the management of HBV in 3 special populations (pregnancy, postliver transplantation, and in the setting of chemotherapy or immunosuppression).

Patients with hematological malignancies and serological signs of prior resolved hepatitis B

Hepatitis B virus (HBV) infection affects a large part of the world population. Within the different virological HBV categories that have been identified, patients with occult HBV infection represent a peculiar group. These individuals harbor a replication competent virus, inhibited in its replicative function. Accordingly, cases of reactivations have been observed in immunosuppressed individuals who lose immunological control over the infection. Patients with hematological malignancies (HM) are treated with intense myelo- and immunosuppressive chemotherapy regimens which favor HBV reactivation. This event can have severe consequences, such as hepatitis flare, hepatic failure and even death. In addition, it can lead to delays or interruptions of curative treatments, resulting in a decreased disease free and overall survival. In this review, we will examine the event of HBV reactivation in patients with signs of resolved HBV infection undergoing treatment for HM and propose possible management strategies.

Should we routinely treat patients with autoimmune/rheumatic diseases and chronic hepatitis B virus infection starting biologic therapies with antiviral agents? NO

Hepatitis B virus (HBV) infection affects a large part of the world population. Different virological HBV categories have been identified and managing strategies for immunosuppressed patients with serological signs of current or past HBV infection has been proposed. Those strategies developed to manage patients in the haematology setting are based on strong evidence. Instead, management of such patients in the rheumatologic setting, especially those treated with biologic response modifiers, is mainly based on data derived by case reports and expert opinions. More data are needed to better manage these patients in case of signs of current or past HBV infection.

The management of chronic hepatitis B in Asian Americans

Hepatitis B virus (HBV) infection is common with major clinical consequences worldwide. In Asian Americans, the HBsAg carrier rate ranges from 7 to 16%; HBV is the most important cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma (HCC). Patients are first diagnosed at different stages of clinical disease, which is categorized by biochemical and virologic tests. Patients at risk for liver complications should be identified and offered antiviral therapy. The two antiviral agents recommended for first-line treatment of chronic hepatitis B (CHB) are entecavir and tenofovir. The primary goal of therapy is sustained suppression of viral replication to achieve clinical remission, reverse fibrosis, and prevent and reduce progression to end-stage liver disease and HCC. Asian patients with chronic hepatitis, either HBeAg-positive or -negative, with HBV DNA levels >10(4) copies/mL (>2,000 IU/mL) and alanine aminotransferase (ALT) values above normal are candidates for antiviral therapy. HBeAg-negative patients with HBV DNA >10(4) copies/mL (>2,000 IU/mL) and normal ALT levels but who have either serum albumin ≤3.5 g/dL or platelet count ≤130,000 mm(3), basal core promoter mutations, or who have first-degree relatives with HCC should be offered treatment. Patients with cirrhosis and detectable HBV DNA must receive antiviral therapy. Considerations for treatment include pregnant women with high viremia, coinfected patients, and those requiring immunosuppressive therapy. In HBsAg-positive patients with risk factors, lifelong surveillance for HCC with alpha-fetoprotein testing and abdominal ultrasound examination at 6-month intervals is required. These recommendations are based on a review of relevant literature and the opinion of a panel of Asian American physicians with expertise in hepatitis B treatment.

Current trends in management of hepatitis B virus reactivation in the biologic therapy era

Hepatitis B virus (HBV) reactivation represents an emerging cause of liver disease in patients undergoing treatment with biologic agents. In particular, the risk of HBV reactivation is heightened by the use monoclonal antibodies, such as rituximab (anti-CD20) and alemtuzumab (anti-CD52) that cause profound and long-lasting immunosuppression. Emerging data indicate that HBV reactivation could also develop following the use of other biologic agents, such as tumor necrosis factor (TNF)-α inhibitors. When HBV reactivation is diagnosed, it is mandatory to suspend biologic treatment and start antiviral agents immediately. However, pre-emptive antiviral therapy prior to monoclonal antibody administration is crucial in preventing HBV reactivation and its clinical consequences. Several lines of evidence have shown that risk of HBV reactivation is greatly reduced by the identification of high-risk patients and the use of prophylactic antiviral therapy. In this article, we discuss current trends in the management of HBV reactivation in immunosuppressed patients receiving biologic therapy, such as rituximab, alemtuzumab and TNF-α antagonists.

Cost-effectiveness of universal hepatitis B virus screening in patients beginning chemotherapy for solid tumors

PURPOSE

Universal screening for chronic hepatitis B virus (HBV) infection before chemotherapy has been recommended. We evaluated the cost-effectiveness of HBV screening before chemotherapy given for nonhematopoietic solid tumors (STs).

METHODS

A decision-analytic model was used to compare the cost-effectiveness of universal screening conducted per professional guidelines versus no screening in hypothetical patient cohorts beginning adjuvant chemotherapy for early breast cancer or palliative chemotherapy for advanced non-small-cell lung cancer. Survival times were extrapolated using Markov models. Probabilities were derived from published studies and costs estimated from the perspective of the Australian health care system. One-way and probabilistic sensitivity analyses were performed, including with the application of an alternative HBV screening strategy.

RESULTS

Using an incremental cost-effectiveness ratio threshold of $50,000 (Australian dollars) per life-year (LY) saved, universal HBV screening was not cost-effective for adjuvant patients ($88,224/LY, 13% probability of being cost-effective), palliative patients ($1,344,251/LY, 0%), or pooled (all) patients ($149,857/LY, 1%). Sensitivity analyses found that screening approached cost-effectiveness among adjuvant patients with the highest reported rates of undiagnosed chronic HBV (65%, $59,445/LY) or HBV reactivation with chemotherapy (41%, $56,537/LY). Cost- effectiveness was also significantly influenced by HBV population prevalence. An alternative screening strategy using hepatitis B surface antigen testing only produced the most economically favorable results, with $30,126/LY (80% probability) for adjuvant patients and $51,201/LY (43%) for the pooled cohort.

CONCLUSION

Universal HBV screening conducted per current guidelines is not cost-effective in patients with STs. Screening may be economically favorable in selected patient subpopulations and/or with simplification of the screening strategy.

Antiviral treatment in patients with hepatitis B virus infection receiving chemotherapy

Reactivation of hepatitis B virus (HBV) is a frequent complication of chemotherapy in patients with HBV infection. Reactivation is characterized by increased levels of serum HBV DNA, abnormal liver function and hepatic failure. HBV reactivation inevitably leads to disruption of chemotherapy and severe clinical results in some cases. Nucleoside analogues play an important role in preventing and reducing the risk for HBV reactivation and HBV-associated morbidity and mortality. This paper gives a systematic review of the definition, mechanism and causes of HBV reactivation and summarizes the principles and problems for antiviral treatment in patients with HBV reactivation. It is strongly recommended that all patients should be screened for HBV serum markers before chemotherapy and preventive therapy with nucleoside analogues be given in patients with HBV. The use of potent antiviral drugs with low resistance potential and close viral monitoring during therapy are important for patients with HBV infection undergoing chemotherapy.

[Current treatment of hepatitis B infection: where do the new nucleos(t)ide analogues fit in?]

One of the most important advances made in the treatment of chronic hepatitis B infection has been the development of nucleos(t)ide analogues. The first antiviral agents used had limited efficacy due to the high resistance rate. However, in the last few years, new agents (tenofovir, entecavir) have been developed with greater antiviral potency and a lower resistance rate. Consequently, these agents are considered to be the treatment of choice in the most recent clinical guidelines. Nevertheless, interferon may still play an important role in the treatment of hepatitis B in selected patients. Moreover, in some contexts, such as renal insufficiency, pregnancy or immunosuppression, the role of the new oral antiviral agents has not been precisely defined. The present review analyzes these aspects, as well as some of the particular features of the management of patients treated with nucleos(t)ide analogues.

Current hepatitis B screening practices and clinical experience of reactivation in patients undergoing chemotherapy for solid tumors: a nationwide survey of medical oncologists

PURPOSE

Universal screening for chronic hepatitis B virus (HBV) before chemotherapy has been recommended by the Centers for Disease Control. We sought to determine the practice of Australian oncologists with regard to HBV screening in patients with solid tumors (STs) and their clinical experience of HBV reactivation (HBVR).

METHODS

A survey was sent to all consultant members of the Medical Oncology Group of Australia. One hundred eighty-eight responses (63% response rate) were received. We also reviewed the incidence of HBV in patients with STs screened at the Peter MacCallum Cancer Centre (Melbourne, Australia).

RESULTS

Fifty-three percent of medical oncologists screen for HBV, but only 19% screen all patients. The most common reasons given for performing screening were anecdotal experience of HBVR (46%) and perceived sufficient evidence for screening of some patient subgroups (42%). Sixty-five percent of those who screened did so only in subgroups, usually selecting patients on the basis of ethnicity (82%). Oncologists who did not screen most commonly cited inadequate evidence for a benefit of screening (72%). Twenty-two percent of oncologists had witnessed one or more HBVR events, representing one event per 45 years of respondents' practice. HBVR events reported (n = 54) consisted of asymptomatic liver test abnormalities only (44%), symptomatic hepatitis (28%), decompensated liver failure (19%), and death (7%). In 206 patients with STs screened for HBV, 1.0% (n = 2) were HBV surface antigen positive, and 14.9% hepatitis B core antibody positive.

CONCLUSION

The majority of Australian medical oncologists have not adopted universal HBV screening before chemotherapy. Further evidence of the benefit and cost effectiveness of universal screening in patients with STs will be required to alter practice.

Hepatitis B Reactivation in a HBsAg-Negative, HBcAb-Positive Patient Receiving Fludarabine for the Treatment of Chronic Lymphocytic Leukaemia

Hepatitis B virus (HBV) reactivation is an increasingly recognized cause of morbidity and mortality in patients undergoing chemotherapy. In haematology, the risk of reactivation of B hepatitis among HBsAg-positive patients has been documented; therefore, use of lamivudine prophylaxis is recommended before starting chemotherapy. Differently, for HBsAg-negative patients with markers of previous HBV infection (i.e., presence of isolated anti-HBc positivity) (anticore patients) management strategies are not univocal. We describe a rare case of HBV reactivation in an anticore patient after fludarabine therapy for chronic lymphocytic leukaemia. The patient fully recovered after a 6-month course of lamivudine with persistent HBV-DNA clearance and loss of HBsAg. The most important feature of this case is that fludarabine alone infrequently determines HBV reactivation, especially in anticore patients. Therefore, we suggest that patients candidates to receive fludarabine therapy should be considered for lamivudine prophylaxis, not only if HBsAg-positive, but even if anticore-positive only.

Hepatitis B virus reactivation in breast cancer patients receiving cytotoxic chemotherapy: a prospective study

Breast cancer is a rapidly increasing problem in many developing countries, and cytotoxic chemotherapy is now an integral part of its management. In several developing countries, the carriage of hepatitis B virus (HBV) in cancer patients may be as high as 12%, and such patients are at risk of developing fatal HBV reactivation during chemotherapy. HBV reactivation is well recognized in patients with hematological malignancies, but limited data are available on patients with other, more common, cancers, such as breast cancer. Recent data have suggested that increased viral replication, an indication of HBV reactivation, may precede clinical hepatitis. In the absence of serial HBV DNA monitoring, HBV reactivation during chemotherapy may have been underestimated. In this prospective study, breast cancer patients who were hepatitis B surface antigen (HBsAg) seropositive were followed up during chemotherapy. The main objectives were to determine the incidence of HBV reactivation in breast cancer patients undergoing conventional chemotherapy; to investigate whether "serial HBV DNA monitoring" improves the accuracy of diagnosing HBV reactivation when compared with previous schema that only measured HBV DNA at the time of clinical hepatitis ("conventional monitoring"); and to assess the clinical consequences as a result of developing the condition. The secondary objective was to identify risk factors associated with this condition. Over an 18-month period, 41 patients were studied. Ten developed HBV reactivation by conventional monitoring criteria, but with serial HBV DNA monitoring, seven additional patients were diagnosed when increased HBV DNA levels were detected before, but not concomitant with, clinical hepatitis. Thus, a total of 17 patients (41%) developed HBV reactivation. Premature termination of chemotherapy or delay in treatment schedules occurred in 71% of the patients who developed viral reactivation, as compared with 33% in those who did not develop the condition (P = 0.019). No risk factors associated with the development of HBV reactivation could be identified. Serial monitoring of HBV DNA, in addition to liver function, increases the sensitivity of diagnosing of HBV reactivation, and helps explain some cases that would otherwise be labeled as "cryptogenic hepatitis," for which concomitant HBV DNA measured at the time of hepatitis was undetectable. The present study highlights the importance of monitoring HBsAg-seropositive patients who are receiving chemotherapy for common solid tumors such as breast cancer.