Cardiovascular toxicities of biological therapies.

The development of biological therapy is based on growing knowledge regarding the molecular changes required in cells for the development and progression of cancer to occur. Molecular targeted therapy is designed to inhibit the major molecular pathways identified as essential for a specific development. This information, in turn, has led to new opportunities for the treatment of cancer. Normal cells, however, are also dependent on these pathways to maintain their function and, consequently, their survival. Interfering with this function in normal cells may result in the risk of serious adverse effects. One serious adverse effect is the risk of cardiovascular dysfunction. Some targeted therapies, eg, treatment with monoclonal antibodies or angiogenesis inhibitors, have shown an increased risk of cardiac events. Their influence on the cardiovascular system, however, seems to be transient, but there is scarce information about their long-term effects for general use. Previous experience with long-term survivors, in whom the risk for cardiac disease seems to increase in subsequent years, has led to concern about patients treated with molecular therapy. This review assesses the currently available knowledge about the risk of cardiotoxicity in targeted therapy for general use.

Recent advances in cardiotoxicity of anticancer therapies.

The treatment of two major diseases in the Western world, cancer and heart disease, has improved significantly in recent years. Today, many more cancers are curable than in previous years. Cancer treatment often consists of chemotherapy, radiation therapy, and now also targeted therapy. All three types of treatment can lead to an increased risk of developing or of worsening a pre-existent cardiovascular disease either during the treatment, immediately afterward, or several years after cessation of therapy. Anthracyclines, a class of drugs that are also known as anthracycline antibiotics, and the drug cisplatin have contributed to the success of cancer treatment. However, these agents can cause cardiovascular disease during treatment, and studies have shown that the risk of disease persists for many years after treatment stops. Irradiation contributes significantly to this risk when the cardiovascular system is part of the radiation field. If the targeted therapy also inhibits the genes responsible for maintaining the function of the cardiovascular system, development of cardiovascular symptoms is inevitable. Therefore, it is essential to have a cardiovascular endpoint in trials with targeted therapy. When treatment stops, however, the effect on the cardiovascular system appears to cease, but it is not known whether the long-term risk of developing cardiovascular disease increases. Combined, these factors indicate that close cooperation between oncologists and cardiologists is essential to optimally benefit patients with cancer.

Systolic versus diastolic cardiac function variables during epirubicin treatment for breast cancer.

Anthracyclines are important in the treatment of numerous malignant diseases but the use is limited by a risk of heart failure (CHF). LVEF (left ventricular ejection fraction) measurements by radionuclide ventriculography with multiple gated acquisition (MUGA) is often used for cardiac monitoring. However, diastolic variables have been proposed as sensitive supplements. It was hypothesized that a change in diastolic filling variables measured by MUGA could identify individuals after epirubicin treatment (ET) in risk of developing heart failure. A retrospective analysis of registered raw data. Individuals completing high-dose ET for breast cancer were selected from a 2-year period. All had MUGA-scans performed prior to and after ET and were observed clinically for late development of CHF. Eleven of 34 individuals developed CHF. A significant LVEF-reduction was recorded after ET with only minor changes in diastolic parameters. Development of CHF was related to dose, entry-blood pressure and inversely to post-epirubicin LVEF. Risk of CHF was high if LVEF <50% (Hazard ratio 3.31). Epirubicin induces considerable decrease in LVEF and a high risk of CHF. The risk of CHF is significantly higher if LVEF is reduced after ET. Diastolic MUGA-variables seem to add little information to conventional measurements of LVEF.

New insight into epirubicin cardiac toxicity: competing risks analysis of 1097 breast cancer patients.

BACKGROUND: Current recommendations that cancer patients receive a maximum cumulative dose of 900 mg/m(2) epirubicin are based on the risk of epirubicin-mediated cardiotoxicity and do not take into account the competing risk of death from cancer. Here, we identify risk factors for cardiotoxicity and overall mortality and determine the cumulative dose of epirubicin that yields a 5% risk for cardiotoxicity for cancer patients from different risk backgrounds. METHODS: Data were collected from 1097 consecutive anthracycline-naive patients treated for metastatic breast cancer with epirubicin. Patients who developed congestive heart failure classified as New York Heart Association class 2 or higher were recorded as having cardiotoxicity. Independent Cox multiple regression analyses for cardiotoxicity and for overall mortality were followed by competing risks analysis, with cardiotoxicity as the primary event and death from all other causes as the competing event. All statistical tests were two-sided. RESULTS: A total of 11.4% of patients developed cardiotoxicity. Risk factors for cardiotoxicity included increased cumulative dose of epirubicin (hazard ratio per every 100 mg/m(2) administered = 1.40, 95% confidence interval = 1.21 to 1.61), patient age, predisposition to cardiac disease, history of mediastinal irradiation, or antihormonal treatment for metastatic disease. Risk factors for death from all other causes (including breast cancer) included lesser dosages of epirubicin, increased tumor burden, prior use of adjuvant chemotherapy, and patient age. The cumulative dosage of epirubicin that carries a 5% risk of cardiotoxicity was lower than previously assumed and was dependent on risks of both cardiotoxicity and overall mortality. CONCLUSION: Maximum cumulative dosages of epirubicin are presented that confer a 5% risk of cardiotoxicity for patients with different sets of risk factors.

Clinical outcome in patients with prostate cancer treated with external beam radiotherapy and high dose-rate iridium 192 brachytherapy boost: a 6-year follow-up.

To report the long-term results for treatment of localized carcinoma of the prostate using high dose rate (HDR) brachytherapy, conformal external beam radiotherapy (3D EBRT) and neo-adjuvant hormonal therapy (TAB). From 1998 through 1999, 154 patients with localized prostate cancer were entered in the trial. Biologically no evidence of disease (bNED) was defined at PSA levels < 2 microg/l. In order to compare the results of this treatment with other treatment modalities, the patient's pre-treatment data were used to calculate the estimated 5-year PSA relapse free survival using Kattan's nomograms for radical prostatectomy (RP) and 3D EBRT. After 6 years of follow-up, 129 patients remain alive. The actual 5-year relapse-free survival is 84%. None of the patients demonstrated clinical signs of local recurrence. The median PSA at follow-up among the relapse-free patients was 0.05 microg/l. Among the 80 patients who presented with clinical stage T3 tumours, 55 (68%) were relapse-free. The expected 5-year relapse-free survival using nomograms for RP and 3D EBRT was 54% and 70%, respectively. Late rectal toxicity RTOG grade 3 occurred in 1% of the patients. Late urinary tract toxicity RTOG grade 3 developed in 4% of the patients. Combined treatment, utilizing HDR, 3D EBRT and TAB, produces good clinical results. Rectal toxicity is acceptable. Urinary tract toxicity, most likely can be explained by the fact that during the first years of this treatment, no effort was made to localize the urethra, which was assumed to be in the middle of the prostate.

Combined curative radiotherapy including HDR brachytherapy and androgen deprivation in localized prostate cancer: a prospective assessment of acute and late treatment toxicity.

Self-reported symptoms including urinary, bowel and sexual side effects were investigated prospectively at multiple assessment points before and after combined radiotherapy of prostate cancer including HDR brachytherapy and neoadjuvant androgen deprivation therapy. Between April 2000 and June 2003, patients with predominantly advanced localized prostate tumours subjected to this treatment were asked before treatment and on follow-up visits to complete a questionnaire covering urinary, bowel and sexual problems. The mainly descriptive analyses included 525 patients, responding to at least one questionnaire before or during the period 2-34 months after radiotherapy. Adding androgen deprivation before radiotherapy significantly worsened sexual function. During radiotherapy, urinary, bowel and sexual problems increased and were reported at higher levels up to 34 months, although there seemed to be a general tendency to less pronounced irritative bowel and urinary tract symptoms over time. No side effects requiring surgery were reported. Classic late irradiation effects such as mucosal bleeding were demonstrated mainly during the second year after therapy, but appear less pronounced in comparison with dose escalated EBRT series. In conclusion, despite the high radiation dose given, the toxicity seemed comparable with that of other series but long term (5-10 years) symptom outcome has to be determined.

Predictors of central nervous system metastasis in patients with metastatic breast cancer. A competing risk analysis of 579 patients treated with epirubicin-based chemotherapy.

In order to identify factors predictive of central nervous system (CNS) metastasis, we reviewed the histories of 579 patients treated with epirubicin-based chemotherapy for metastatic breast cancer. Statistical analysis included Kaplan-Meier survival plots, Cox's regression analysis and competing risk analysis using the cumulative incidence. Median follow-up-time was 137 months (range 0-183+). In this period, one hundred and twenty-four patients (21.4%) developed CNS metastasis. Lung, liver, and lymph node metastases and oestrogen receptor negative or unknown tumor were predictive as well. However, increased pretreatment lactate dehydrogenase (LDH) concentration in serum above the upper normal limits was the strongest single risk factor and should therefore be measured. The risk of CNS metastasis differed considerably among risk groups. Patients without risk factors had a cumulative incidence on 9%, compared to a cumulative incidence of 42%, when the serum LDH concentration was elevated to more than twice the upper normal limits.

Palliation of bone pain in prostate cancer using chemotherapy and strontium-89. A randomized phase II study.

Strontium-89 is an established alternative for the alleviation of bone pain in prostate cancer. There are few data evaluating the effect on pain of palliative chemotherapy. The aim of this randomized phase II study was to assess and compare the analgesic efficacy of strontium-89 and chemotherapy (FEM=5-FU, epirubicin, and mitomycin C) in 35 patients with disseminated, hormone-refractory prostate cancer suffering from persisting bone pain despite analgesic treatment. In order to minimize the risk for imbalances regarding the two patient groups, a double-blind randomization was performed. A significant reduction in pain intensity and pain frequency was registered in both patient groups (P < 0.01 in both groups after 3 weeks). Side effects were generally mild in the strontium-89 group and significantly more severe in the FEM group. The effect of FEM on pain is surprising as chemotherapy has generally only limited effect on tumor growth in bone metastases due to prostate cancer. A possible explanation is that FEM has an inhibitory activity on the inflammatory component of metastases.