Pattern of Liver Disease Following High-Dose Cytosine Arabinoside (HDARAC) Therapy in Children with Acute Myeloid Leukemia

Hepatic late adverse effects after antineoplastic treatment for childhood cancer

BACKGROUND

Survival rates have greatly improved as a result of more effective treatments for childhood cancer. Unfortunately, the improved prognosis has been accompanied by the occurrence of late, treatment-related complications. Liver complications are common during and soon after treatment for childhood cancer. However, among long-term childhood cancer survivors, the risk of hepatic late adverse effects is largely unknown. To make informed decisions about future cancer treatment and follow-up policies, it is important to know the risk of, and associated risk factors for, hepatic late adverse effects. This review is an update of a previously published Cochrane review.

OBJECTIVES

To evaluate all the existing evidence on the association between antineoplastic treatment (that is, chemotherapy, radiotherapy involving the liver, surgery involving the liver and BMT) for childhood cancer and hepatic late adverse effects.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2018, Issue 1), MEDLINE (1966 to January 2018) and Embase (1980 to January 2018). In addition, we searched reference lists of relevant articles and scanned the conference proceedings of the International Society of Paediatric Oncology (SIOP) (from 2005 to 2017) and American Society of Pediatric Hematology/Oncology (ASPHO) (from 2013 to 2018) electronically.

SELECTION CRITERIA

All studies, except case reports, case series, and studies including fewer than 10 patients that examined the association between antineoplastic treatment for childhood cancer (aged 18 years or less at diagnosis) and hepatic late adverse effects (one year or more after the end of treatment).

DATA COLLECTION AND ANALYSIS

Two review authors independently performed the study selection and 'risk of bias' assessment. The 'risk of bias' assessment was based on earlier checklists for observational studies. For the original version of the review, two review authors independently performed data extraction. For the update of the review, the data extraction was performed by one reviewer and checked by another reviewer.

MAIN RESULTS

Thirteen new studies were identified for the update of this review. In total, we included 33 cohort studies including 7876 participants investigating hepatic late adverse effects after antineoplastic treatment (especially chemotherapy and radiotherapy) for different types of childhood cancer, both haematological and solid malignancies. All studies had methodological limitations. The prevalence of hepatic late adverse effects, all defined in a biochemical way, varied widely, between 0% and 84.2%. Selecting studies where the outcome of hepatic late adverse effects was well-defined as alanine aminotransferase (ALT) above the upper limit of normal, indicating cellular liver injury, resulted in eight studies. In this subgroup, the prevalence of hepatic late adverse effects ranged from 5.8% to 52.8%, with median follow-up durations varying from three to 23 years since cancer diagnosis in studies that reported the median follow-up duration. A more stringent selection process using the outcome definition of ALT as above twice the upper limit of normal, resulted in five studies, with a prevalence ranging from 0.9% to 44.8%. One study investigated biliary tract injury, defined as gamma-glutamyltransferase (γGT) above the upper limit of normal and above twice the upper limit of normal and reported a prevalence of 5.3% and 0.9%, respectively. Three studies investigated disturbance in biliary function, defined as bilirubin above the upper limit of normal and reported prevalences ranging from 0% to 8.7%. Two studies showed that treatment with radiotherapy involving the liver (especially after a high percentage of the liver irradiated), higher BMI, and longer follow-up time or older age at evaluation increased the risk of cellular liver injury in multivariable analyses. In addition, there was some suggestion that busulfan, thioguanine, hepatic surgery, chronic viral hepatitis C, metabolic syndrome, use of statins, non-Hispanic white ethnicity, and higher alcohol intake (> 14 units per week) increase the risk of cellular liver injury in multivariable analyses. Chronic viral hepatitis was shown to increase the risk of cellular liver injury in six univariable analyses as well. Moreover, one study showed that treatment with radiotherapy involving the liver, higher BMI, higher alcohol intake (> 14 units per week), longer follow-up time, and older age at cancer diagnosis increased the risk of biliary tract injury in a multivariable analysis.

AUTHORS' CONCLUSIONS

The prevalence of hepatic late adverse effects among studies with an adequate outcome definition varied considerably from 1% to 53%. Evidence suggests that radiotherapy involving the liver, higher BMI, chronic viral hepatitis and longer follow-up time or older age at follow-up increase the risk of hepatic late adverse effects. In addition, there may be a suggestion that busulfan, thioguanine, hepatic surgery, higher alcohol intake (>14 units per week), metabolic syndrome, use of statins, non-Hispanic white ethnicity, and older age at cancer diagnosis increase the risk of hepatic late adverse effects. High-quality studies are needed to evaluate the effects of different therapy doses, time trends, and associated risk factors after antineoplastic treatment for childhood cancer.

Hepatic late adverse effects after antineoplastic treatment for childhood cancer

BACKGROUND

Survival rates have greatly improved as a result of more effective treatments for childhood cancer. Unfortunately the improved prognosis has resulted in the occurrence of late, treatment-related complications. Liver complications are common during and soon after treatment for childhood cancer. However, among long-term childhood cancer survivors the risk of hepatic late adverse effects is largely unknown. To make informed decisions about future cancer treatment and follow-up policies it is important to know the risk of, and associated risk factors for, hepatic late adverse effects.

OBJECTIVES

To evaluate the existing evidence on the association between antineoplastic treatment for childhood cancer and hepatic late adverse effects.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2009, Issue 2), MEDLINE (1966 to June 2009) and EMBASE (1980 to June 2009). In addition, we searched reference lists of relevant articles and conference proceedings.

SELECTION CRITERIA

All studies except case reports, case series and studies including less than 10 patients that examined the association between antineoplastic treatment for childhood cancer (aged 18 years or less at diagnosis) and hepatic late adverse effects (one year or more after the end of treatment).

DATA COLLECTION AND ANALYSIS

Two review authors independently performed the study selection, risk of bias assessment and data extraction.

MAIN RESULTS

We identified 20 cohort studies investigating hepatic late adverse effects after antineoplastic treatment for childhood cancer. All studies had methodological limitations. The prevalence of hepatic late adverse effects varied widely, between 0% and 84.2%. Selecting studies where the outcome of hepatic late adverse effects was well defined as alanine aminotransferase (ALT) above the upper limit of normal resulted in five studies. In this subgroup the prevalence of hepatic late adverse effects ranged from 8.0% to 52.8%, with follow-up durations varying from one to 27 years after the end of treatment. A more stringent selection process using the outcome definition of ALT as above twice the upper limit of normal resulted in three studies, with a prevalence ranging from 7.9% to 44.8%. Chronic viral hepatitis was identified as a risk factor for hepatic late adverse effects in univariate analyses. It is unclear which specific antineoplastic treatments increase the risk of hepatic late adverse effects

AUTHORS' CONCLUSIONS

The prevalence of hepatic late adverse effects ranged from 7.9% to 52.8% when selecting studies with an adequate outcome definition. It has not been established which childhood cancer treatments result in hepatic late adverse effects. There is a suggestion that chronic viral hepatitis increases the risk of hepatic late adverse effects. More well-designed studies are needed to reliably evaluate the prevalence of, and risk factors for, hepatic late adverse effects after antineoplastic treatment for childhood cancer.

Hepatitis C virus serum markers and liver disease in children with leukemia

This review summarises serologic profiles and clinical features of HCV infection in children with leukemia. The diagnosis of HCV infection is currently based on the detection in serum of antiviral antibodies and HCV-RNA. Studies on leukemic children, however, have clearly shown that only HCV-RNA testing correctly identifies HCV infection, as specific antibodies become detectable in serum only after chemotherapy withdrawal in almost all cases. Viraemia instead appears early in the course of leukemia, and infected patients become carriers. The pattern of liver disease is rather homogeneous. Early onset, persisting ALT elevation during chemotherapy often with drastic reduction during high-dose chemotherapy, followed by sharp exacerbations of liver cell necrosis. ALT normalise after chemotherapy withdrawal in most cases, despite persisting viraemia. As regards to the ultimate prognosis of liver disease in these children, we have observed that, among a series of 119 patients followed for at least 10 years off-therapy, none has developed clinical decompensated liver disease and only 6% still has abnormal ALT levels. On the other hand, the need for prolonged follow-up of children surviving leukemia with chronic HCV infection is emphasized by the fact that the natural history of HCV infection has not been fully clarified and that additional late sequelae are likely to occur.

Evidence against the role of hepatitis C virus in severe liver damage occurring early in the course of acute leukemia in children

Severe liver damage revealed by a sharp transaminase elevation may be seen in patients with leukemia. This may be due to several possible causes, including viral hepatitis, chemotherapy-induced hepatotoxicity and leukemic infiltration. HCV infection may be suspected to play a relevant role as these patients are often heavily transfused after the onset of their hematologic disorder. We have therefore examined the role of HCV in 15 children with leukemia who developed severe liver damage shortly after the diagnosis of leukemia. All patients were tested for HCV-RNA by the polymerase chain reaction at the time of peak SGPT elevation and for anti-HCV on serial serum samples taken thereafter. Only one patient (6.6%) showed hepatitis C viremia and none developed confirmed anti-HCV positivity during follow-up, suggesting that HCV had not played a major role in causing these severe episodes of liver necrosis. This is in agreement with observations made in non-immunocompromised patients in whom fulminant hepatitis is only exceptionally due to HCV.