Long-term heart function after adjuvant epirubicin chemotherapy for breast cancer

Assessment of Long-term Follow-up of Randomized Trial Participants by Linkage to Routinely Collected Data: A Scoping Review and Analysis

Importance

Follow-up of participants in randomized trials may be limited by logistic and financial factors. Some important randomized trials have been extended well beyond their original follow-up period by linkage of individual participant information to routinely collected data held in administrative records and registries.

Objective

To perform a scoping review of randomized clinical trials extended by record linkage to characterize this literature and explore any additional insights into treatment effectiveness provided by long-term follow-up using record linkage.

Data Sources

A literature search in Embase, CINAHL, MEDLINE, and the Cochrane Register of Controlled Trials was performed for the period January 1, 1945, through November 25, 2016.

Study Selection

Various combinations of search terms were used, as there is no accepted terminology. Determination of study eligibility and extraction of information about trial characteristics and outcomes, for both original and extended trial reports, were performed in duplicate.

Data Extraction and Synthesis

Assessment of study eligibility and data extraction were performed independently by 2 reviewers. All analyses were descriptive.

Main Outcomes and Measures

Outcomes in the pairs of original and extended trials were categorized according to whether any benefits or harms from interventions were sustained, were lost, or emerged during long-term follow-up.

Results

A total of 113 extended trials were included in the study. Linkage to administrative and registry data extended follow-up by between 1 and 55 years. The most common interventions were pharmaceuticals (47 [41.6%]), surgery (19 [16.8%]), and disease screening (19 [16.8%]). End points most frequently studied through record linkage included mortality (88 [77.9%]), cancer (41 [36.3%]), and cardiovascular events (37 [32.7%]). One hundred four trial extensions (92.0%) were analyzed according to the original trial randomization. The reports provided details of 155 analyses of study outcomes. Seventy-four analyses (47.7%) identified statistically significant benefits in the trial extension phase. In 21 of these (28.4%), benefits were significant only in this period. Null results in both the original and extended trials were seen in 34 of the analyses (21.9%). Loss of significant benefits of an intervention were seen in 12 analyses (7.7%). Statistically significant harms were seen in 16 trial extension analyses (10.3%), and in 14 of these (87.5%), the harms were significant only in the trial extension phase.

Conclusions and Relevance

Trial extension by linkage to routinely collected data is a versatile underused approach that may add critical insights beyond those of the original trial. Some beneficial and harmful outcomes of interventions are captured only in the extension phase of randomized trials.

Biomarkers for monitoring chemotherapy-induced cardiotoxicity

Cardiotoxicity, including acute and late-onset cardiotoxicity, is a well-known adverse effect of many types of antitumor agents. Early identification of patients with cardiotoxicity is important to ensure prompt treatment and minimize toxic effects. The etiology of chemotherapy-induced cardiotoxicity is multifactorial. Traditional methods for assessment of chemotherapy-induced cardiotoxicity typically involve serial measurements of cardiac function via multi-modality imaging techniques. Typically, however, significant left ventricular dysfunction has already occurred when cardiotoxicity is detected by imaging techniques. Biomarkers, most importantly cardiac natriuretic peptides and troponins, are promising markers for identifying patients potentially at risk for clinical heart failure symptoms. This review summarizes the recent progress in clinical utilization of biomarkers for early diagnosis of acute cardiotoxicity and for prediction of late-onset cardiotoxicity. We also discuss the conflicting results of different studies and the association of results with study design.

An epirubicin-peptide conjugate with anticancer activity is dependent upon the expression level of the surface transferrin receptor

Epirubicin (EPI) is one of the most widely used anticarcinogens; however, serious side effects, including cardiomyopathy and congestive heart failure, limit its long‑term administration. To overcome this problem, the HAIYPRH peptide ligand was used with EPI in the synthesis of a HAIYPRH‑EPI conjugate. The anticancer activity and cellular uptake of the conjugate were measured and evaluated. The results of the present study indicated that the cytotoxicity of HAIYPRH‑EPI was correlated with the expression of the cell surface transferrin receptor (TfR). The conjugate exerted high cytotoxicity and proapoptotic function when in an LN229 glioma cell line, which overexpresses surface TfR. It was hypothesized that transferrin (Tf) can promote cytotoxicity. Conversely, the conjugate exhibited very low cytotoxicity and proapoptotic function in a U87 glioma cell line, in which surface TfR expression was undetectable. In addition, fluorescence microscopy and flow cytometry methods were used to evaluate cellular uptake, and the results of these methods were consistent with the present hypotheses. The conjugate cellular uptake of the conjugate in LN229 cells was markedly higher compared with that in U87 cells, and it was hypothesized that Tf can enhance the uptake in LN229 cells. The cytotoxicity of HAIYPRH‑EPI was dependent upon the expression of surface TfR. Considering that the majority of cancer cells have high rates of iron uptake and surface TfR is generally overexpressed on cancer cells, it was speculated by the authors that HAIYPRH‑EPI may form part of an effective strategy for increasing the selectivity of EPI for cancer cells, as well as reducing its systemic toxicity. To confirm the hypothesis, the effects of HAIYPRH‑EPI on non‑cancerous cell lines were investigated. A future study will examine the side effects of HAIYPRH‑EPI, using a suitable delivery system in an animal model.

Serum biomarkers evaluation to predict chemotherapy-induced cardiotoxicity in breast cancer patients

Anti-neoplastic chemotherapy can determine various side effects, including cardiotoxicity, and no real guidelines for its early detection and management have been developed. The aim of this study is to find some plasmatic markers able to identify breast cancer patients that are at greater risk of developing cardiovascular complications during chemotherapy, in particular heart failure. A prospective study on 100 breast cancer patients with mean age of 66 years in adjuvant treatment with anthracyclines, taxanes, and trastuzumab was performed. Patients underwent cardiological examination before starting treatment (T0) and at 3 months (T1), 6 months (T2), and 1 year (T3) after treatment. Evaluation of serum cardiac markers and N-terminal pro-brain natriuretic peptide (NT-proBNP) was performed at T0, T1, T2, and T3, simultaneously to electrocardiogram and echocardiogram, showing a significant increase in NT-proBNP concentration (p > 0.0001) at T1, T2, and T3, before left ventricular ejection fraction decrease became evident. Human epidermal growth factor receptor 2 (HER2)-negative patients were more susceptible to mild hematological cardiotoxicity, while HER2-positive patients were more susceptible to severe cardiotoxicity. A significant correlation between NT-proBNP increased values after chemotherapy and prediction of mortality at 1 year was evidenced. From our experience, serum biomarker detection was able to support an early diagnosis of cardiac damage, also in the absence of left ventricular ejection fraction decrease. Therefore, the evaluation of specific plasmatic markers for cardiac damage is more sensitive than echocardiography in the early diagnosis of chemotherapy-related cardiotoxicity; furthermore, it can also add a prognostic value on outcome.

Evaluation of epirubicin in thermogelling and bioadhesive liquid and solid suppository formulations for rectal administration

Temperature sensitive Pluronic (Plu) and pH-sensitive polyacrylic acid (PAA) were successfully mixed in different ratios to form in situ gelling formulations for colon cancer therapy. The major formulations were prepared as the liquid and solid suppository dosage forms. Epirubicin (Epi) was chosen as a model anticancer drug. In vitro characterization and in vivo pharmacokinetics and therapeutic efficacy of Epi in six Plu/PAA formulations were evaluated. Our in vitro data indicate that Epi in Plu 14%/PAA 0.75% of both solid and liquid suppositories possess significant cytotoxicity, strong bioadhesive force, long-term appropriate suppository base, sustained release, and high accumulation of Epi in rat rectums. These solid and liquid suppositories were retained in the upper rectum of Sprague-Dawley (SD) rats for at least 12 h. An in vivo pharmacokinetic study using SD rats showed that after rectal administration of solid and liquid suppositories, Epi had greater area under the curve and higher relative bioavailability than in a rectal solution. These solid and liquid suppositories exhibited remarkable inhibition on the tumor growth of CT26 bearing Balb/c mice in vivo. Our findings suggest that in situ thermogelling and mucoadhesive suppositories demonstrate a great potential as colon anticancer delivery systems for protracted release of chemotherapeutic agents.

Temporal changes in standard and tissue Doppler imaging echocardiographic parameters after anthracycline chemotherapy in women with breast cancer

Anthracyclines are established cardiotoxic agents; however, the exact extent and time course of such cardiotoxicity has not been appraised in detail. We aimed to exploit serial measurements of standard and tissue Doppler imaging (TDI) echocardiographic parameters collected in a prospective clinical trial to clarify the outlook of cardiac function during and long after anthracycline chemotherapy. Women enrolled in a randomized trial focusing on liposomal doxorubicin-based chemotherapy for breast cancer and providing ≥4 separate echocardiographic assessments were included. Repeat-measure nonparametric analyses were used to appraise changes over time in the standard and tissue Doppler imaging echocardiographic parameters. A total of 39 patients with serial imaging evaluations were enrolled. Significant temporal changes were found for the left ventricular ejection fraction and diastolic parameters, despite different temporal trends. Specifically, the left ventricular ejection fraction exhibited a V-shaped trend, decreasing initially from 63% to 61% but then recovering to 64% (p <0.001), with a similar trend in the TDI E/Em ratio (p = 0.011). In contrast, persistent impairments typical of an L-shaped trend were found for the E wave (p = 0.006), TDI lateral Em wave (p = 0.001), and TDI septal Em wave (p = 0.001). In conclusion, subclinical temporal changes in the standard and TDI echocardiographic parameters after anthracycline chemotherapy showed a distinctive pattern of transient impairment followed by full recovery of the left ventricular ejection fraction versus a persistent impairment of the diastolic parameters, which must be taken into account in the everyday treatment of such patients.