Potential role of epicardial adipose tissue as a biomarker of anthracycline cardiotoxicity.

BACKGROUND: We investigated the radiodensity of epicardial (EAT), subcutaneous (SAT), and visceral adipose tissue (VAT) before and after treatment with anthracyclines in a population of breast cancer (BC) patients, and in controls not treated with anthracyclines, to detect a potential role of EAT density as a biomarker of changes related to chemotherapy cardiotoxicity. METHODS: We reviewed BC patients treated with anthracyclines who underwent CT before (CT-t0) and after (CT-t1) chemotherapy, and age- and sex-matched controls who underwent two CT examinations at comparable intervals. On non-contrast scans, EAT was segmented contouring the pericardium and thresholding between -190 and -30 Hounsfield units (HU), and SAT and VAT were segmented with two 15-mm diameter regions of interest thresholded between -195 and -45 HU. RESULTS: Thirty-two female patients and 32 controls were included. There were no differences in age (p = 0.439) and follow-up duration (p = 0.162) between patients and controls. Between CT-t0 and CT-t1, EAT density decreased in BC patients (-66 HU, interquartile range [IQR] -71 to -63 HU, to -71 HU, IQR -75 to -66 HU, p = 0.003), while it did not vary in controls (p = 0.955). SAT density increased from CT-t0 to CT-t1 in BC patients (-107 HU, IQR -111 to -105 HU, to -105 HU, IQR -110 to -100 HU, p = 0.014), whereas it did not change in controls (p = 0.477). VAT density did not vary in either BC patients (p = 0.911) or controls (p = 0.627). CONCLUSIONS: EAT density appears to be influenced by anthracycline treatment for BC, well known for its cardiotoxicity, shifting towards lower values indicative of a less active metabolism.

Assessment of myocardial extracellular volume on body computed tomography in breast cancer patients treated with anthracyclines.

BACKGROUND: Cancer treatment with anthracyclines may lead to an increased incidence of cardiac disease due to cardiotoxicity, as they may cause irreversible myocardial fibrosis. So far, the proposed methods for screening patients for cardiotoxicity have led to only limited success, while the analysis of myocardial extracellular volume (mECV) at cardiac magnetic resonance (CMR) has shown promising results, albeit requiring a dedicated exam. Recent studies have found strong correlations between mECV values obtained through computed tomography (CT), and those derived from CMR. Thus, our purpose was to evaluate the feasibility of estimating mECV on thoracic contrast-enhanced CT performed for staging or follow-up in breast cancer patients treated with anthracyclines, and, if feasible, to assess if a rise in mECV is associated with chemotherapy, and persistent over time. METHODS: After ethics committee approval, female patients with breast cancer who had undergone at least 2 staging or follow-up CT examinations at our institution, one before and one shortly after the end of chemotherapy including anthracyclines were retrospectively evaluated. Patients without available haematocrit, with artefacts in CT images, or who had undergone radiation therapy of the left breast were excluded. Follow-up CT examinations at longer time intervals were also analysed, when available. mECV was calculated on scans obtained at 1, and 7 min after contrast injection. RESULTS: Thirty-two female patients (aged 57±13 years) with pre-treatment haematocrit 38%±4%, and ejection fraction 64%±6% were analysed. Pre-treatment mECV was 27.0%±2.9% at 1 min, and 26.4%±3.8% at 7 min, similar to values reported for normal subjects in the literature. Post-treatment mECV (median interval: 89 days after treatment) was 31.1%±4.9%, and 30.0%±5.1%, respectively, values significantly higher than pre-treatment values at all times (P<0.005). mECV at follow-up (median interval: 135 days after post-treatment CT) was 31.0%±4.5%, and 27.7%±3.7%, respectively, without significant differences (P>0.548) when compared to post-treatment values. CONCLUSIONS: mECV values from contrast-enhanced CT scans could play a role in the assessment of myocardial condition in breast cancer patients undergoing anthracycline-based chemotherapy. CT-derived ECV could be an imaging biomarker for the monitoring of therapy-related cardiotoxicity, allowing for potential secondary prevention of cardiac damage, using data derived from an examination that could be already part of patients' clinical workflow.

Is a dexamethasone-sparing strategy capable of preventing acute and delayed emesis caused by combined doxorubicin and paclitaxel for breast cancer? Analysis of a phase II trial.

OBJECTIVE: The effectiveness of palonosetron without delayed dexamethasone dosing against emesis was investigated in patients scheduled to receive the corticosteroid-containing combination of doxorubicin and paclitaxel (AT) for 3 cycles. METHODS: Chemo-naïve women with breast cancer receiving doxorubicin (60 mg/m(2)) and paclitaxel (200 mg/m(2)) were eligible. Patients received palonosetron 0.25 mg intravenously before chemotherapy, however, all patients also received a premedication consisting of prednisone (25 mg orally the evening before therapy) and hydrocortisone (250 mg intravenously just before paclitaxel). The primary end point was complete control (CC; no vomiting, no rescue anti-emetics, and no more than mild nausea) during the overall phase (days 1-5) following cycle 1. RESULTS: Seventy-six patients were enrolled and evaluable (median age 50 years). Fifty-six patients (74%; 95% CI 62-83%) achieved overall CC. Acute (day 1) and delayed (days 2-5) CC rates were 78 and 74%, respectively. No vomiting rates for the acute, delayed and overall phases were 85, 85 and 83%, respectively. An exploratory analysis showed only a small decrease in the probability of achieving CC between cycle 1 (74%) and cycle 3 (66%). CONCLUSION: The dexamethasone-sparing strategy prevented emesis in more than 70% of breast cancer patients receiving their initial cycle of AT chemotherapy.

A phase I study of ixabepilone in combination with epirubicin in patients with metastatic breast cancer.

UNLABELLED: In this phase I trial, 42 women with metastatic breast cancer were treated with a fixed dose of epirubicin (75 mg/m2) and escalating doses of ixabepilone (25, 30, and 35 mg/m2). The maximum-tolerated dose of ixabepilone in combination with epirubicin was 30 mg/m2 (the recommended dose for phase II evaluation), and the dose-limiting toxicity dose was 35 mg/m2 with grade 4 neutropenia. PURPOSE: The objectives of this phase I trial were to determine the maximum-tolerated dose (MTD), toxicity profile, dose-limiting toxicities (DLT), pharmacokinetics, and the recommended phase II dose for ixabepilone in combination with epirubicin in women with metastatic breast cancer. PATIENTS AND METHODS: Patients ≥18 years old with an histologically or cytologically confirmed diagnosis of invasive breast cancer and clinical evidence of locally recurrent or metastatic disease were enrolled and treated with a fixed dose of epirubicin (75 mg/m(2)) and escalating doses of ixabepilone (25, 30, and 35 mg/m(2)). RESULTS: Forty-two women were treated at 3 different dose levels of ixabepilone: 25 (n = 6), 30 (n = 30), and 35 mg/m(2) (n = 6) in combination with 75 mg/m(2) epirubicin. The MTD of ixabepilone in combination with epirubicin 75 mg/m(2) was 30 mg/m(2), and the DLT dose was 35 mg/m(2) with grade 4 neutropenia. Grade 3/4 neutropenia was the most frequent moderate-to-severe adverse event and was manageable and reversible. No deaths were reported. Objective responses were achieved in 18 of 32 patients with measurable disease (56% [90% CI, 40%-71%]) and in 9 of 22 evaluable patients treated at the MTD (41% [90% CI, 23%-61%]). Ixabepilone clearance and the epirubicin pharmacokinetic profile were similar across ixabepilone dose levels. CONCLUSIONS: The combination of ixabepilone and epirubicin was clinically active. The recommended dose for evaluation in phase II is epirubicin 75 mg/m(2), followed by ixabepilone 30 mg/m(2) every 3 weeks.

Pathological complete response rates following different neoadjuvant chemotherapy regimens for operable breast cancer according to ER status, in two parallel, randomized phase II trials with an adaptive study design (ECTO II).

Sequential doxorubicin/paclitaxel (AT) followed by CMF treatment was shown to be an active neoadjuvant chemotherapy regimen in the first European Cooperative Trial in Operable Breast Cancer (ECTO I trial). The aim of the current study (ECTO II) is to assess the complete pathological response (pCR) rate following three different anthracycline and taxane-containing neoadjuvant chemotherapy regimens, with or without capecitabine (X). Patients with operable, invasive breast cancer > 2.0 cm in diameter, were randomized to AT→CMF, AT→CMX or AC→TX regimens in two parallel, randomized, open-label, phase II trials (within a single study) in patients with estrogen receptor negative (ER-) and estrogen receptor positive (ER+) diseases, respectively. Exemestane was delivered concomitantly with neoadjuvant chemotherapy in ER+ tumors. Achievement of pCR was more common in ER- than ER+ women (45.3 vs. 10.4%). Capecitabine was only associated with a higher frequency of pCR in ER+ patients receiving AT→CMX. Overall response rates (ORR) ranged from 88 to 97%, and this translated into high rates of breast-conserving surgery (67% of ER- patients and 72% of ER+ patients). All three regimens were well tolerated. Febrile neutropenia and gastrointestinal effects were the most common grade ≥ 3 adverse events. As expected, the ECTO II study showed higher pCR rates in patients with ER- disease. Substituting capecitabine for fluorouracil (± methotrexate) in anthracycline/taxane-containing regimens appeared to be beneficial only in ER+ tumors. Translational studies investigating interactions between therapeutic agents and tumor biology are warranted to refine patient selection and improve the results of neoadjuvant chemotherapy.

Trastuzumab as adjuvant systemic therapy for HER2-positive breast cancer.

Trastuzumab has an established role for the treatment of HER2-positive early-stage breast cancer because of the success of this agent in the adjuvant setting. Several key questions about the value of trastuzumab for the treatment of breast cancer, however, still need to be answered. Various differences in patient characteristics and treatment regimens were present in the randomized trials discussed in this Review; therefore, the details of trastuzumab use need clarification. For example, the optimum timing, the ideal administration schedule, and the appropriate length of treatment are not known. Cardiotoxicity is major concern even though the results of all randomized trials have shown that the degree of cardiotoxicity with trastuzumab is acceptable -- the incidence of cardiac damage caused by trastuzumab ranged from 0.4% to 4.1% in the different trials (cumulative incidence of congestive heart failure, New York Heart Association class 3-4). Current data do not support the use of trastuzumab for more than 1 year. The analysis of 2-year treatment with trastuzumab is expected to be available in 2009.