Subclinical cardiotoxicity following adjuvant dose-escalated FEC, high-dose chemotherapy, or CMF in breast cancer

Comprehensive review on cardio-oncology: Role of multimodality imaging

Cancer and cardiovascular disease are the two leading causes of mortality worldwide. Evolving oncologic therapy, including the use of newer targeted agents, has led to an improvement in survival from childhood- and adult-onset cancers. Consequently, there has been a growing realization of cardiotoxic complications related to cancer therapy, with some complications manifesting over months to decades after completion of cancer treatment. This paper reviews cancer therapeutics-related cardiovascular toxicity and its manifestations, multimodality imaging techniques for surveillance and detection of this complication, and the current state of knowledge in this emerging field.

Combination chemotherapy with cyclophosphamide, epirubicin and 5-fluorouracil causes trabecular bone loss, bone marrow cell depletion and marrow adiposity in female rats

The introduction of anthracyclines to adjuvant chemotherapy has increased survival rates among breast cancer patients. Cyclophosphamide, epirubicin and 5-fluorouracil (CEF) combination therapy is now one of the preferred regimens for treating node-positive breast cancer due to better survival with less toxicity involved. Despite the increasing use of CEF, its potential in causing adverse skeletal effects remains unclear. Using a mature female rat model mimicking the clinical setting, this study examined the effects of CEF treatment on bone and bone marrow in long bones. Following six cycles of CEF treatment (weekly intravenous injections of cyclophosphamide at 10 mg/kg, epirubicin at 2.5 mg/kg and 5-flurouracil at 10 mg/kg), a significant reduction in trabecular bone volume was observed at the metaphysis, which was associated with a reduced serum level of bone formation marker alkaline phosphatase (ALP), increased trends of osteoclast density and osteoclast area at the metaphysis, as well as an increased size of osteoclasts being formed from the bone marrow cells ex vivo. Moreover, a severe reduction of bone marrow cellularity was observed following CEF treatment, which was accompanied by an increase in marrow adipose tissue volume. This increase in marrow adiposity was associated with an expansion in adipocyte size but not in marrow adipocyte density. Overall, this study indicates that six cycles of CEF chemotherapy may induce some bone loss and severe bone marrow damage. Mechanisms for CEF-induced bone/bone marrow pathologies and potential preventive strategies warrant further investigation.

Efficacy of variable dosage of aspirin in combating methotrexate-induced intestinal toxicity

The aim of the present study was to study in detail the effect of variable doses of aspirin on intestinal toxicity.

Evidence-based risk assessment and recommendations for physical activity clearance: cancer

Physical activity is becoming increasingly acknowledged as an integral component of in the multidisciplinary management of cancer patients. Intensive inquiry in this area is likely to increase further over the next decade; however, cancer-specific, evidence-based risk assessment and recommendations for physical activity are not available. A systematic literature review was performed of all studies conducting an exercise training intervention and (or) any form of objective exercise test among adults diagnosed with cancer. Studies were assessed according to evaluation criteria developed by a panel of experts. A total of 118 studies involving 5529 patients were deemed eligible. Overall, the results suggest that exercise training and maximal and submaximal exercise testing are relatively safe procedures with a total nonlife-threatening adverse event rate of <2%. There was only 1 exercise training-related death. However, the quality of exercise testing methodology and data reporting is less than optimal. Thus, whether the low incidence of events reflects the true safety of exercise training and exercise testing in cancer patients or less than optimal methodology and (or) data reporting remains to be determined. Evidence-based absolute and relative contraindications to physical activity and exercise training and testing are provided as well as probing decision-trees to optimize the adoption and safety of physical activity in persons diagnosed with cancer.

Three versus six months of exercise training in breast cancer survivors

Breast cancer is the most prevalent type of cancer in American women. Exercise appears to diminish many of the side effects resulting from breast cancer and its treatment. Very little research, however, has compared the outcomes of varying lengths of combined aerobic and resistance training exercise interventions on physiological and psychological parameters in breast cancer survivors. The purpose of this study was to compare the physiological and psychological outcomes following 3 and 6 months of exercise in breast cancer survivors. Breast cancer survivors (N = 114) participated in either 3 months of prescriptive, individualized exercise (3M; n = 29), 6 months of prescriptive, individualized exercise (6M; n = 68), or served as sedentary controls (C; n = 17). Cancer survivors completed a medical evaluation and assessment at baseline followed by a predetermined 3- or 6-month exercise intervention. Cancer survivors in the control group performed no exercise between the initial assessment and 6-month reassessment. Cardiovascular endurance, pulmonary function, muscular endurance, fatigue, and symptoms of depression were assessed at baseline and post intervention. Repeated measures ANCOVA revealed improvements (P < 0.05) in cardiovascular endurance, fatigue, and symptoms of depression in breast cancer survivors undergoing 3- and 6-month individualized exercise interventions. Breast cancer survivors exercising for 6 months showed additional improvements (P < 0.05) in pulmonary function and muscular endurance. Cancer survivors in the control group did not improve in cardiovascular endurance, pulmonary function, muscular endurance, or fatigue. Three months of individualized, prescriptive exercise leads to improved cardiovascular endurance, fatigue, and symptoms of depression in breast cancer survivors. Additional benefits are seen if exercise is continued for a total of 6 months.

Long-term follow-up of the SBG 9401 study comparing tailored FEC-based therapy versus marrow-supported high-dose therapy

BACKGROUND

The purpose was to investigate adjuvant marrow-supportive high-dose chemotherapy compared with an equitoxicity-tailored comparator arm.

PATIENTS AND METHODS

Five hundred and twenty-five women below the age of 60 years with operated high-risk primary breast cancer were randomised to nine cycles of granulocyte colony-stimulating factor supported and individually tailored FEC (5-fluorouracil, epirubicin, cyclophosphamide), (n = 251) or standard FEC followed by marrow-supported high-dose therapy with CTCb (cyclophosphamide, thiotepa, carboplatin) therapy (n = 274), followed by locoregional radiotherapy and tamoxifen for 5 years.

RESULTS

There were 104 breast cancer relapses in the tailored FEC group versus 139 in the CTCb group (double triangular method by Whitehead, P = 0.046), with a median follow-up of all included patients of 60.8 months. The event-free survival demonstrated 121 and 150 events in the tailored FEC- and CTCb group, respectively [P = 0.074, hazard ratio (HR) 0.804, 95% confidence interval (CI) 0.633-1.022]. Ten patients in the tailored FEC regimen developed acute myeloid leukaemia (AML)/myelodysplasia (MDS). One hundred deaths occurred in the tailored FEC group and 121 in the CTCb group (P = 0.287, HR 0.866, 95% CI 0.665-1.129).

CONCLUSION

The update of this study shows an improved outcome linked to the tailored FEC treatment in relation to breast cancer relapse, but also an increased incidence of AML/MDS.

Diabetes, hypertension, and cardiovascular events in survivors of hematopoietic cell transplantation: a report from the bone marrow transplantation survivor study

We ascertained the prevalence of self-reported late occurrence of diabetes, hypertension, and cardiovascular (CV) disease in 1089 hematopoietic cell transplantation (HCT) survivors who underwent HCT between 1974 and 1998, survived at least 2 years, and were not currently taking immunosuppressant agents and compared them with 383 sibling controls. All subjects completed a 255-item health questionnaire. The mean age at survey completion was 39.3 years for survivors and 38.6 years for siblings; mean follow-up was 8.6 years. Adjusting for age, sex, race, and body mass index (BMI), survivors of allogeneic HCT were 3.65 times (95% confidence interval [CI], 1.82-7.32) more likely to report diabetes than siblings and 2.06 times (95% CI, 1.39-3.04) more likely to report hypertension compared with siblings but did not report other CV outcomes with any greater frequency. Recipients of autologous HCTs were no more likely than siblings to report any of the outcomes studied. Allogeneic HCT survivors were also more likely to develop hypertension (odds ratio [OR]=2.31; 95% CI, 1.45-3.67) than autologous recipients. Total body irradiation (TBI) exposure was associated with an increased risk of diabetes (OR=3.42; 95% CI, 1.55-7.52). Thus, HCT survivors have a higher age- and BMI-adjusted risk of diabetes and hypertension, potentially leading to a higher than expected risk of CV events with age.

Cardiac toxicity of high-dose chemotherapy

Cardiac toxicity is an uncommon but potentially serious complication of high-dose (HD) chemotherapy and little is known about incidence, severity and underlying mechanisms. We have systematically reviewed the literature of the last 30 years to summarize and appraise the published evidence on cardiac toxicity associated with HD chemotherapy. HD cyclophosphamide-containing regimens have been most commonly associated with cardiac toxicity, with a progressively decreasing incidence over time. Dosage, application regimens and coadministration of other chemotherapeutic agents emerged as risk factors. While cardiac toxicity has been rarely associated with other cytotoxic drugs, an unexpected incidence of severe cardiotoxicity resulted from reduced-intensity conditioning regimens containing melphalan and fludarabine. Predictive value of cardiologic examination of patients is limited, and patients with a slight depression of cardiac performance could tolerate HD chemotherapy. Clinical examination, resting electrocardiography and dosage adjustment in overweight patients remain the mainstay of prevention, with bidimensional echocardiography (2D echo) for patients with a history of anthracycline exposure. Strategies to decrease the long-term negative impact of anthracycline administration on cardiac performance are being investigated. New 2D echo-based techniques and circulating markers of cardiac function hold promise for allowing identification of patients at high risk for and early diagnosis of cardiac toxicity.

Prevalence of the metabolic syndrome in relation to self-reported cancer history

PURPOSE

To estimate the prevalence of metabolic syndrome in persons with a history of cancer from a population-based sample of adults, and compare that prevalence to persons without a history of cancer.

METHODS

Data from the Third National Health and Nutrition Examination Survey were analyzed to compare prevalence and prevalence differences of the metabolic syndrome, as defined by Adult Treatment Panel III criteria, between 486 persons with a reported history of cancer and 12,526 persons with no reported history of cancer.

RESULTS

The prevalence of metabolic syndrome was 258/1000 persons for those with a cancer history and 184/1000 persons among those without, resulting in a prevalence difference of 74/1000 persons (95% CI, 38-110). Prevalence differences varied substantially by age at interview. The prevalence difference was highest among those aged 40 to 49 years (112/1000 persons) and 50 to 59 years (73/1000 persons), while those in younger (18-39 years) and older (: 60 years) age groups had a moderately higher prevalence among those without a cancer history.

CONCLUSION

These results add to the emerging concern that metabolic syndrome and associated risks for cardiovascular disease and type 2 diabetes may be an adverse late effect of cancer and/or its treatment.

Monitoring of cardiac function on the basis of serum troponin I levels in patients with acute leukemia treated with anthracyclines

Anthracyclines are used extensively in the therapy of hematologic malignancies. However, their use has been limited by acute and chronic cardiotoxicity. Cardiac troponins have emerged as sensitive and specific markers of even minor myocardial damage. In this study we prospectively evaluated serial measurements of serum cardiac markers and echocardiography in patients with de novo acute myeloid and lymphoid leukemias (AML and ALL, respectively) treated with anthracyclines. We examined and subdivided 79 patients into 3 groups: group 1 (37 patients with AML, all < 60 years), group 2 (25 with AML, all 260 years), group 3 (17 with ALL). Serum specimens were collected before treatment and during and after therapy and were analyzed for troponin I (Tnl), myoglobin, creatine phosphokinase-muscle myocardium isoenzyme B, and lactate dehydrogenase concentrations. In group 1, 4 of the 37 patients (11%) had increased levels of Tnl on the 14th day of induction therapy, but by the 28th day the Tnl level had returned to normal in 3 of these 4 patients. In group 2, 3 of the 25 patients (12%) demonstrated increased Tnl concentrations on the 7th day of induction therapy, but by the 14th day these levels had normalized in 2 of the 3. In group 3, we detected no increased Tnl concentrations. Echographic study did show a significant correlation with the Tnl levels (P < .001), involving a reversible decrease in left ventricular ejection fraction among patients with increased Tnl levels (> 0.15 ng/mL) on day 14 in group 1 and on day 7 in group 2. These results may aid the clinician in the treatment of patients by identifying high-risk patients who may benefit from closer observation or supportive cardiac therapy.

Predicting cancer therapy-induced cardiotoxicity: the role of troponins and other markers

Several anticancer drugs have been associated with cardiac toxicity, especially the anthracyclines and trastuzumab. The pathogenesis of anthracycline-associated toxicity has been well described, whereas the mechanism of trastuzumab-associated toxicity is unknown. Although routine cardiac imaging studies (e.g. echocardiogram or multiple gated acquisition scans) may identify subclinical evidence of myocardial dysfunction, available data do not support their routine use for monitoring asymptomatic patients undergoing cancer therapy. Other modalities such as nuclear medicine scintigraphy with indium-111-antimyosin antibody and endomyocardial biopsy have been shown to be useful in identifying early cardiac damage, but their routine use is limited by practical considerations such as feasibility and cost. Consequently, there is significant interest in developing simple and reproducible methods for identifying patients at risk for treatment-induced myocardial damage. Available data suggest that circulating markers such as troponins and natriuretic peptides could potentially be useful for this purpose. Measurement of plasma troponin levels are commonly used in clinical practice in order to provide diagnostic and prognostic information in patients with myocardial ischaemia. Elevated levels may likewise correlate with anthracycline-induced cardiac damage, although plasma levels are only minimally elevated (well below that associated with ischaemia), and elevations may persist for weeks or months after anthracycline exposure. Clinical trials are currently evaluating the role of these markers in predicting both early and late, clinical and subclinical damage associated with anthracyclines and trastuzumab.

Pulmonary toxicity after radiotherapy in primary breast cancer patients: results from a randomized chemotherapy study

PURPOSE

Pulmonary toxicity was prospectively evaluated within a randomized trial for breast cancer patients at high risk for relapse, who postoperatively received as adjuvant therapy either 9 cycles of tailored chemotherapy (20 patients) (cyclophosphamide, epirubicin, 5-fluorouracil [FEC]) or standard FEC x 3 followed by high-dose chemotherapy (cyclophosphamide, thiotepa, carboplatin [CTCb]) supported by peripheral blood stem cell transplantation (14 patients). After high-dose chemotherapy or tailored FEC, all patients received locoregional radiotherapy (50 Gy/5 weeks), plus tamoxifen for 5 years.

METHODS AND MATERIALS

Lung function tests (FVC, FEV1, and DL(CO)) were performed before chemotherapy and 9 months after radiotherapy. Computed tomography of the lungs was performed before radiotherapy and 6 weeks, 3 months, and 9 months after radiotherapy.

RESULTS

Clinical signs of suspected pneumonitis were noted in 29% of patients, but only 1 patient needed symptomatic therapy. Radiologic changes were detected in 68% of patients, and they were most frequent at 3 months after radiotherapy. FVC decreased in both groups (tailored FEC: mean difference, -6.5%, p = 0.0005; CTCb: -2.0%, p = 0.21; tailored FEC vs. CTCb: -4.5%, p = 0.05). DL(CO) decreased significantly in both groups (tailored FEC: mean difference, -11.2%, p < 0.0001; CTCb: -5.6%, p = 0.02; tailored FEC vs. CTCb: -5.6%, p = 0.07). FEV1 decreased by 7.3% in patients treated with tailored FEC (p < 0.0001) and by 2.5% in patients treated with CTCb (p = 0.03) (tailored FEC vs. CTCb: 3.7%, p = 0.08).

CONCLUSIONS

Changes in pulmonary function were thus detected in both groups, although to a greater extent in the tailored FEC group. The clinical significance of these findings should be balanced carefully against the improved, statistically significant relapse-free survival achieved with the tailored FEC regimen compared to high-dose CTCb + peripheral blood stem cell transplantation (PSCT).

Trastuzumab therapy and the heart: palliation at what cost?

Trastuzumab (Herceptin®), a monoclonal HER2 receptor blocker, was approved by the Food and Drug Administration in September, 1998 for the treatment of advanced breast carcinoma. It is rapidly emerging as an important drug for the treatment of metastatic breast cancer. The results of a pivotal trial revealed a 53% improvement in the response rate when trastuzumab was added to the standard chemotherapeutic regimen. However, a greater than four-fold increase in the occurrence of congestive heart failure was also noted. This novel agent has ushered in hope for thousands of women, but its use mandates that a clear understanding of its effects and relative risks be appreciated. Careful patient selection for the use of trastuzumab is critically important. It is prudent that cardiologists be aware of its cardiotoxicity, and that the risk/benefit ratio be clarified before its use in less invasive forms of breast cancer. (c)2001 CHF, Inc.

Effects of dose-intensive chemotherapy and radiotherapy on serum n-terminal proatrial natriuretic peptide in high-risk breast cancer patients

By using N-terminal proatrial natriuretic peptide (proANP) in serum as a marker of cardiac function, we compared the cardiac side effects of two intensive adjuvant treatment regimens for breast cancer. Patients received either 9 cycles of FEC (5-fluorouracil, epirubicin and cyclophosphamide) where the doses of epirubicin and cyclophosphamide were escalated according to the leucocyte nadir (n = 49, FEC-group) or three cycles of FEC followed by high-dose chemotherapy with alkylating agents (n = 56, CTCb-group) given with the support of peripheral blood stem cells support. Both groups received adjuvant radiotherapy. Serial measurements of proANP were performed up to three years after treatment. Mean proANP values in the FEC-group was on average 19% higher than in the CTCb-group (p = 0.002). The proANP levels showed a significant association with the cumulative dose of epirubicin (p < 0.001) but not with cyclophosphamide (p = 0.151) and 5-FU (p = 0.160). The pharmacokinetics of epirubicin was studied at the first and third chemotherapy course. The proANP levels after treatment were significantly related to the AUC (p = 0.034) and Cmax(p = 0.037) of epirubicin. Left-sided chest irradiation was associated with on average 12% higher proANP values than right-sided (p = 0.031). We conclude that dose-escalated FEC causes a stronger increase in proANP than 3 FEC followed by high-dose CTCb-treatment. Increase of proANP levels might represent an early sign of cardiotoxicity secondary to chemotherapy and radiation treatment. Long-time follow-up is necessary to determine the clinical significance of these findings.

Prospective Evaluation of Early Cardiac Damage Induced by Epirubicin-Containing Adjuvant Chemotherapy and Locoregional Radiotherapy in Breast Cancer Patients

PURPOSE: To evaluate prospectively the cardiotoxic effects of epirubicin-containing adjuvant chemotherapy in breast cancer patients.

PATIENTS AND METHODS: Patients (median age, 46 years; range, 28 to 55 years) were treated with five cycles of fluorouracil, epirubicin (90 mg/m2), and cyclophosphamide (FEC) (group I, n = 21) or with four cycles of FEC followed by high-dose chemotherapy consisting of cyclophosphamide, thiotepa, and carboplatin (group II, n = 19). Locoregional radiotherapy was applied subsequently. Cardiac evaluation was performed before chemotherapy (T0), 1 month after chemotherapy, 1 month after radiotherapy (T2), and 1 year after start of chemotherapy (T3). Left ventricular ejection fraction (LVEF) was determined by radionuclide ventriculography and diastolic function by echocardiography. Autonomic function was assessed by 24-hour ECG registration for heart rate variability (HRV) analysis. Time-corrected QT (QTc) was assessed and N-terminal atrial natriuretic peptide (NT-ANP) and brain natriuretic peptide (BNP) were measured as biochemical markers of cardiac dysfunction.

RESULTS: No patient developed overt congestive heart failure (CHF) and the mean LVEF declined from 0.61 at T0 to 0.54 at T3 (P = .001), resulting in an LVEF below 0.50 (range, 0.42 to 0.49) in 17% of the patients, whereas 28% had a decline of more than 0.10. Plasma NT-ANP levels increased gradually from 237 pmol/L at T0 to 347 pmol/L at T3 (P < .01), whereas plasma BNP levels increased from 2.9 pmol/L to 5.1 pmol/L (P = .04). Mean QTc increased from 406 msec at T0 to 423 msec at T3 (P < .01). No persistent alterations were found in diastolic function and HRV.

CONCLUSION: Relatively low doses of epirubicin in adjuvant chemotherapy for breast cancer results in mild subclinical myocardial damage demonstrated by a decline in LVEF, an increase in natriuretic peptide levels, and an increase in QTc, which may indicate a long-term risk of CHF.