Different dosage schedules for reducing damage to the heart in people with cancer receiving anthracycline chemotherapy

Review question
We reviewed the evidence of different anthracycline dosage schedules to cause damage to the heart in people with cancer of all ages receiving anthracycline chemotherapy. We also looked at tumour response, participant survival, adverse effects other than damage to the heart, and quality of life.

Background
Anthracyclines are one of the most effective treatments for various types of cancer. Unfortunately, there is a risk of heart damage depending on the total dose a patient has received. In an effort to prevent heart damage, different anthracycline dosage schedules such as different infusion durations or different individual peak doses (the maximal dose received in one week) are being used.

Study characteristics
The evidence is current to December 2015.

We found 11 studies: 7 evaluated different infusion durations (803 participants), and 4 evaluated different peak doses (5280 participants). Participants had different types of cancer.

Key results
For the use of different anthracycline infusion durations, the authors found that an anthracycline infusion duration of six hours or longer reduces the risk of clinical heart failure (for example shortness of breath or leg oedema), and it seems to reduce the risk of subclinical heart failure (that is heart damage diagnosed for example by an echocardiography in people without symptoms). Only a small amount of data was available for children and individuals with leukaemia, since most studies evaluating different anthracycline infusion durations were performed in adults with solid tumours.

Based on the currently available evidence, we are not able to favour either a doxorubicin peak dose of less than 60 mg/m2 or 60 mg/m2 or more. There was not enough high-quality evidence available for the use of other anthracycline peak doses to be able to draw conclusions. No data were available for children and individuals with leukaemia.

Further high-quality research is needed.

Quality of the evidence
All studies had problems relating to quality of the evidence.

Authors' conclusions: 

An anthracycline infusion duration of six hours or longer reduces the risk of clinical heart failure, and it seems to reduce the risk of subclinical cardiac damage. Since there is only a small amount of data for children and data obtained in adults cannot be extrapolated to children, different anthracycline infusion durations should be evaluated further in children.

We identified no significant difference in the occurrence of clinical heart failure in participants treated with a doxorubicin peak dose of less than 60 mg/m2 or 60 mg/m2 or more. Only one RCT was available for the other identified peak doses, so we can make no definitive conclusions about the occurrence of cardiotoxicity. More high-quality research is needed, both in children and adults and in leukaemias and solid tumours.

Read the full abstract...
Background: 

This review update has been managed by both the Childhood Cancer and Cochrane Gynaecological, Neuro-oncology and Orphan Cancer Groups.

The use of anthracycline chemotherapy is limited by the occurrence of cardiotoxicity. To prevent this cardiotoxicity, different anthracycline dosage schedules have been studied.

Objectives: 

To determine the occurrence of cardiotoxicity with the use of different anthracycline dosage schedules (that is peak doses and infusion durations) in people with cancer.

Search strategy: 

We searched the databases of the Cochrane Register of Controlled Trials (CENTRAL) (the Cochrane Library, Issue 11, 2015), MEDLINE (1966 to December 2015), and EMBASE (1980 to December 2015). We also searched reference lists of relevant articles, conference proceedings, experts in the field, and ongoing trials databases.

Selection criteria: 

Randomised controlled trials (RCTs) in which different anthracycline dosage schedules were compared in people with cancer (children and adults).

Data collection and analysis: 

Two review authors independently performed the study selection, the 'Risk of bias' assessment, and data extraction. We performed analyses according to the guidelines of the Cochrane Handbook for Systematic Reviews of Interventions.

Main results: 

We identified 11 studies: 7 evaluated different infusion durations (803 participants), and 4 evaluated different peak doses (5280 participants). Seven studies were RCTs addressing different anthracycline infusion durations; we identified long-term follow-up data for one of the trials in this update. The meta-analysis showed a statistically significant lower rate of clinical heart failure with an infusion duration of six hours or longer as compared to a shorter infusion duration (risk ratio (RR) 0.27; 95% confidence interval 0.09 to 0.81; 5 studies; 557 participants). The majority of participants included in these studies were adults with different solid tumours. For different anthracycline peak doses, we identified two RCTs addressing a doxorubicin peak dose of less than 60 mg/m2 versus 60 mg/m2 or more, one RCT addressing a liposomal doxorubicin peak dose of 25 mg/m2 versus 50 mg/m2, and one RCT addressing an epirubicin peak dose of 83 mg/m2 versus 110 mg/m2. A significant difference in the occurrence of clinical heart failure was identified in none of the studies. The participants included in these studies were adults with different solid tumours. High or unclear 'Risk of bias' issues were present in all studies.