Cumulative Dose Of Doxorubicin Research Articles

Diversifying the anthracycline class of anti-cancer drugs identifies aclarubicin for superior survival of acute myeloid leukemia patients

The efficacy of anthracycline-based chemotherapeutics, which include doxorubicin and its structural relatives daunorubicin and idarubicin, remains almost unmatched in oncology, despite a side effect profile including cumulative dose-dependent cardiotoxicity, therapy-related malignancies and infertility. Detoxifying anthracyclines while preserving their anti-neoplastic effects is arguably a major unmet need in modern oncology, as cardiovascular complications that limit anti-cancer treatment are a leading cause of morbidity and mortality among the 17 million cancer survivors in the U.S. In this study, we examined different clinically relevant anthracycline drugs for a series of features including mode of action (chromatin and DNA damage), bio-distribution, anti-tumor efficacy and cardiotoxicity in pre-clinical models and patients. The different anthracycline drugs have surprisingly individual efficacy and toxicity profiles. In particular, aclarubicin stands out in pre-clinical models and clinical studies, as it potently kills cancer cells, lacks cardiotoxicity, and can be safely administered even after the maximum cumulative dose of either doxorubicin or idarubicin has been reached. Retrospective analysis of aclarubicin used as second-line treatment for relapsed/refractory AML patients showed survival effects similar to its use in first line, leading to a notable 23% increase in 5-year overall survival compared to other intensive chemotherapies. Considering individual anthracyclines as distinct entities unveils new treatment options, such as the identification of aclarubicin, which significantly improves the survival outcomes of AML patients while mitigating the treatment-limiting side-effects. Building upon these findings, an international multicenter Phase III prospective study is prepared, to integrate aclarubicin into the treatment of relapsed/refractory AML patients.

Incidence of cardiotoxicity after high cumulative dose of anthracyclines in adult patients with advanced soft tissue sarcomas: A systematic review and meta-analysis.

e24004 Background: The risk of anthracycline-related cardiotoxicity increases with cumulative dose, with most available literature based from studies on breast cancer patients. Although soft tissue sarcomas are heterogenous entities, anthracycline-based chemotherapy is considered the most active regimen. This study aims to clarify the incidence of cardiotoxicity among patients with advanced soft tissue sarcomas who receive a high cumulative dose of anthracyclines. Methods: We performed a systematic search across PubMed, Cochrane, Google Scholar, and ASCO and ESMO references. Studies were eligible if they (1) investigated soft tissue sarcoma patients, (2) receiving high cumulative doses of doxorubicin ( > 450mg/m2), lipodox ( > 550mg/m2) or epirubicin ( > 900mg/m2), and (3) reported the incidence of cardiotoxicity (clinical and subclinical). Three authors independently assessed validity of the articles using the Cochrane Tool for randomized trials and the Newcastle-Ottawa scale for cohorts. Pooled analysis was performed using MetaXL with the random effects model. Pooled incidence with 95% CI and heterogeneity (Cochran's Q) were determined. Results: For doxorubicin, 4 studies with 168 patients without pre-existing cardiomyopathy, and a mean age of 47 years were included. At a mean cumulative dose of 651.1mg/m2, clinical cardiotoxicity was seen in 2.6% (0.62–5.62%,Q3) while subclinical cardiotoxicity was seen in 23.8%(17.67%-30.53%,Q86). For epirubicin, we included 3 studies with 109 patients, without pre-existing cardiomyopathy, and mean age of 39 years. At a cumulative dose of 1128.33mg/m2, clinical cardiotoxicity was seen in 5.3% (1.74–10.38%,Q25), and subclinical cardiotoxicity was seen in 13.4% (7.62%-20.50%,Q37). Conclusions: The incidence of cardiotoxicity in patients with advanced soft tissue sarcomas receiving high cumulative dose of anthracyclines is comparable with existing data on breast, lymphoma and leukemia patients. Subclinical cardiotoxicity is more prominent. Majority of the patients received cardioprotective strategies during their treatment (dexrazoxane or continuous infusions of doxorubicin). Evidence with regard to lipodox is lacking.

Doxorubicin-induced neurotoxicity differently affects the hippocampal formation subregions in adult mice

Doxorubicin (DOX) is an anthracycline used to treat a wide range of tumours. Despite its effectiveness, it is associated with a long range of adverse effects, of which cognitive deficits stand out. The present study aimed to assess the neurologic adverse outcome pathways of two clinically relevant cumulative doses of DOX. Adult male CD-1 mice received biweekly intraperitoneal administrations for 3 weeks until reaching cumulative doses of 9 mg/kg (DOX9) or 18 mg/kg (DOX18). Animals were euthanized one week after the last administration, and biomarkers of oxidative stress and brain metabolism were evaluated in the whole brain. Coronal sections of fixed brains were used for specific determinations of the prefrontal cortex (PFC) and hippocampal formation (HF). In the whole brain, DOX18 tended to disrupt the antioxidant defences, affecting glutathione levels and manganese superoxide dismutase expression. Considering the regional analysis, DOX18 increased the volume of all brain areas evaluated, while GFAP-immunoreactive astrocytes decreased in the dentate gyrus (DG) and increased in the CA3 region of HF, both in a dose-dependent manner. Concerning the apoptosis pathway, whereas Bax increased in the DOX9 group, it decreased in the DOX18 group. Only in the latter group did Bcl-2 levels also decrease. While p53 only increased in the CA3 region of the DOX9 group, AIF increased in the PFC and DG of DOX18. Finally, phosphorylation of Tau decreased with the highest DOX dose in DG and CA3, while TNF-α levels increased in CA1 of DOX18. Our results indicate new pathways not yet described that could be responsible for the cognitive impairments observed in treated patients.

Early myocardial injury in children on doxorubicin for cancer chemotherapy: a cross-sectional study in a tertiary referral centre in Kenya

IntroductionUse of doxorubicin, an anthracycline chemotherapeutic agent has been associated with late-occurring cardiac toxicities. Detection of early-occurring cardiac effects of cancer chemotherapy is essential to prevent occurrence of adverse events including toxicity, myocardial dysfunction, and death.ObjectiveTo investigate the prevalence of elevated cardiac troponin T (cTnT) and associated factors of myocardial injury in children on doxorubicin cancer chemotherapy.MethodsDesign: A cross-sectional study.Setting and subjects: A hospital-based study conducted on children aged 1-month to 12.4-years who had a diagnosis of cancer and were admitted at Kenyatta National Hospital (KNH).Interventions and outcomes: The patients underwent Echocardiography (ECHO) before their scheduled chemotherapy infusion. Twenty-four (24) hours after the chemotherapy infusion the patients had an evaluation of the serum cardiac troponin T (cTnT) and a repeat ECHO. Myocardial injury was defined as cTnT level > 0.014 ng/ml or a Fractional Shortening (FS) of < 29% on ECHO.ResultsOne hundred (100) children were included in the final analysis. Thirty-two percent (32%) of the study population had an elevated cTnT. A cumulative doxorubicin dose of > 175 mg/m2 was significantly associated with and elevated cTnT (OR, 10.76; 95% CI, 1.18–97.92; p = 0.035). Diagnosis of nephroblastoma was also associated with an elevated cTnT (OR, 3.0; 95% CI, 1.23–7.26) but not statistically significant (p = 0.105). Nine percent (9%) of the participants had echocardiographic evidence of myocardial injury.ConclusionWhen compared to echocardiography, elevated levels of cTnT showed a higher association with early-occurring chemotherapy-induced myocardial injury among children on cancer treatment at a tertiary teaching and referral hospital in Kenya.

Effects of pharmacogenetics on pharmacokinetics and toxicity of doxorubicin in Egyptian breast cancer patients

This study investigates the impact of single nucleotide polymorphisms in genes (SLC22A16 and CBR1) involved in the pharmacokinetics and toxicity of doxorubicin (DOX) in Egyptian female patients with breast cancer. Patients administered DOX (60 mg/m2) for 4 cycles every 3 weeks. The peak DOX plasma concentration was measured using a validated chromatographic method. The genotyping for the selected SNPs, SLC22A16 T > C (rs714368), and CBR1 C > T (rs20572), was performed by RT-PCR. Patients were monitored for hematological and cardiac toxicities. The variant carriers of CBR1 C > T (rs20572) exhibited significantly higher DOX concentration, but no significant association to DOX-induced hematological toxicity. On the other hand, SLC22A16 T > C (rs714368) had no significant influence on DOX plasma concentration, but was significantly correlated with lower risk of neutropenia (OR 0.31, 95% CI 0.12–0.75, p = 0.01) and leukopoenia (OR 0.18, 95% CI 0.07–0.5, p = 0.001). DOX-related cardiotoxicity was correlated with the cumulative dose of DOX (R = 0.238, p = 0.017), but not with any of the two examined SNPs. Genetic polymorphisms in SLC22A16 and CBR1 may explain the inter-individual variations in DOX pharmacokinetics and toxicity. Using pharmacogenetic testing is important to customise drug therapy for cancer patients treated with anthracyclines.

Doxorubicin Exposure and Breast Cancer Risk in Survivors of Adolescent and Adult Hodgkin Lymphoma.

Female Hodgkin lymphoma (HL) survivors treated with chest radiotherapy (RT) at a young age have a strongly increased risk of breast cancer (BC). Studies in childhood cancer survivors have shown that doxorubicin exposure may also increase BC risk. Although doxorubicin is the cornerstone of HL chemotherapy, the association between doxorubicin and BC risk has not been examined in HL survivors treated at adult ages. We assessed BC risk in a cohort of 1,964 female 5-year HL survivors, treated at age 15-50 years in 20 Dutch hospitals between 1975 and 2008. We calculated standardized incidence ratios, absolute excess risks, and cumulative incidences. Doxorubicin exposure was analyzed using multivariable Cox regression analyses. After a median follow-up of 21.6 years (IQR, 15.8-27.1 years), 252 women had developed invasive BC or ductal carcinoma in situ. The 30-year cumulative incidence was 20.8% (95% CI, 18.2 to 23.4). Survivors treated with a cumulative doxorubicin dose of >200 mg/m2 had a 1.5-fold increased BC risk (95% CI, 1.08 to 2.1), compared with survivors not treated with doxorubicin. BC risk increased 1.18-fold (95% CI, 1.05 to 1.32) per additional 100 mg/m2 doxorubicin (Ptrend = .004). The risk increase associated with doxorubicin (yes v no) was not modified by age at first treatment (hazard ratio [HR]age <21 years, 1.5 [95% CI, 0.9 to 2.6]; HRage ≥21 years, 1.3 [95% CI, 0.9 to 1.9) or chest RT (HRwithout mantle/axillary field RT, 1.9 [95% CI, 1.06 to 3.3]; HRwith mantle/axillary field RT, 1.2 [95% CI, 0.8 to 1.8]). This study shows that treatment with doxorubicin is associated with increased BC risk in both adolescent and adult HL survivors. Our results have implications for BC surveillance guidelines for HL survivors and treatment strategies for patients with newly diagnosed HL.

QTc intervals at rest and during exercise assessed by group correction formulas in survivors of childhood acute lymphoblastic leukemia

IntroductionEarly signs of subclinical cardiac damage must be identified before they turn into clinical manifestations. Tailoring a formula is relevant for precise QTc evaluation in childhood acute lymphoblastic leukemia (ALL) survivors considering they are at risk of long-term cardiac problems. Therefore, we aim to develop group heart rate correction formulas for QT intervals in childhood ALL survivors at rest and during exercise, and to assess the applicability of these methods across a variety of risk groups exposed to diverse chemotherapy dosages. MethodsTwo hundred and fifty childhood ALL survivors in the PETALE study were classified into 3 groups depending on their prognostic risk group. ECG measurements (QT and RR intervals) were made at rest and during a cardiopulmonary exercise test. QT correction for heart rate was applied using 5 different formulas, which included 2 previously published formulas and 3 group-specific formulas for each sex. ResultsThe QT/RR relation showed 2 different curves between rest and during exercise, which was worse for females. Group-specific QTc formulas allowed adequate heart rate-corrected QT interval, independently of the cumulative dose of doxorubicin received during treatment. Group-specific formulas showed significantly shorter QTc intervals than QTc from Bazett's formula. QTc (Bazett's formula) values surpassed the established clinical norm in 22 males (11%) and 22 females (11%), with a majority occurring during exercise, affecting 15 males (7.5%) and 10 females (5%). ConclusionThis study shows the applicability of personalized group correction of QT/RR data in childhood ALL survivors. Our comprehensive assessments (spanning rest, exercise, and recovery) is an effective approach for risk stratification of cardiac complications in childhood ALL survivors.

Left ventricular mechanical dyssynchrony after chemotherapy in breast cancer patients with normal rest gated SPECT-MPI.

Early diagnosis of chemotherapy-induced cardiotoxicity plays an important role in preventing heart failure. The main aim of our study was to assess left ventricular (LV) dyssynchrony measured by phase analysis of gated single-photon emission computed tomography (SPECT) as an early sign of cardiotoxicity after breast cancer chemotherapy. This cross-sectional study was conducted on patients with stage ≤ 3 breast cancer and no history of cardiovascular disease or diabetes. After mastectomy, the patients underwent rest gated SPECT myocardial perfusion imaging (MPI). Sixty patients with normal gated SPECT-MPI were selected and the imaging was performed after chemotherapy with doxorubicin, cyclophosphamide and paclitaxel. LV function and contractility parameters were extracted by QGS software and the results were compared with the t test method. The abnormality of at least one of the three phase analysis indices was considered as left ventricular dyssynchrony (LVD). The average LV end-systolic volume and ejection fraction (LVEF) before and after chemotherapy were (16.2 ± 8.0ml and 21.6 ± 11.6ml) and (73.4 ± 7.9% and 67.5 ± 9.2%) respectively, which showed a significant decrease (P < 0.05). In 2 patients (3.3%), the LVEF decreased to less than 50% after chemotherapy. The average parameters of left ventricular contractility before and after chemotherapy were, respectively, as follows: PHB (24.1 ± 7.5 and 33.8 ± 16.4), PSD (9.4 ± 6.1 and 5.7 ± 1.9) and entropy (28.9 ± 7.1 and 35.6 ± 9.7), which showed a significant increase (P < 0.05). LVD was observed in 14 patients (23.4%) after chemotherapy and prevalence of LVD was significantly higher in patients who had received a cumulative dose of doxorubicin of more than 400mg/m2 (P = 0.005). There was no relationship between age and body mass index with the incidence of LVD after chemotherapy (P > 0.05). Using phase analysis of gated SPECT-MPI, chemotherapy-induced LVD was seen in a significant number of patients with breast cancer, especially with a high cumulative dose of doxorubicin. LVD might indicate chemotherapy-induced cardiotoxicity before LVEF becomes abnormal.

Late Cardiac Toxic Effects Associated With Treatment Protocols for Hodgkin Lymphoma in Children

Contemporary North American trials for children with Hodgkin lymphoma (HL) have decreased radiation therapy (RT) use and increased pharmacologic cardioprotection but also increased the cumulative doxorubicin dose, making overall treatment consequences for late cardiac toxic effects uncertain. To estimate the risk of cardiac toxic effects associated with treatments used in modern pediatric HL clinical trials. For this cohort study, Fine and Gray models were fitted using survivors in the Childhood Cancer Survivor Study who were diagnosed with HL between January 1, 1970, and December 31, 1999, and were followed for a median of 23.5 (range, 5.0-46.3) years. These models were applied to the exposures in the study population to estimate the 30-year cumulative incidence of cardiac disease. The study population comprised patients with intermediate-risk or high-risk HL treated in 4 consecutive Children's Oncology Group clinical trials from September 2002 to October 2022: AHOD0031, AHOD0831, AHOD1331, and S1826. Data analysis was performed from April 2020 to February 2023. All patients received chemotherapy including doxorubicin, and some patients received mediastinal RT, dexrazoxane, or mediastinal RT and dexrazoxane. Estimated 30-year cumulative incidence of grade 3 to 5 cardiac disease. The study cohort comprised 2563 patients, with a median age at diagnosis of 15 (range, 1-22) years. More than half of the patients were male (1357 [52.9%]). All 2563 patients received doxorubicin, 1362 patients (53.1%) received mediastinal RT, and 307 patients (12.0%) received dexrazoxane. Radiation therapy use and the median mean heart dose among patients receiving RT decreased, whereas the planned cumulative dose of doxorubicin and use of dexrazoxane cardioprotection increased. For patients treated at age 15 years, the estimated 30-year cumulative incidence of severe or fatal cardiac disease was 9.6% (95% CI, 4.2%-16.4%) in the AHOD0031 standard treatment group (enrolled 2002-2009), 8.6% (95% CI, 3.8%-14.9%) in the AHOD0831 trial (enrolled 2009-2012), 8.2% (95% CI, 3.6%-14.3%) in the AHOD1331 trial (enrolled 2015-2019), and 6.2% (95% CI, 2.7%-10.9%) in the S1826 trial (enrolled 2019-2022), whereas the expected rate in an untreated population was 5.0% (95% CI, 2.1%-9.3%). Despite the estimated reduction in late cardiac morbidity, the frequency of recommended echocardiographic screening among survivors will increase based on current guidelines. In this cohort study of sequential HL trials, reductions in the proportion of children receiving mediastinal RT and increases in dexrazoxane use were estimated to offset the increased doxorubicin dose and produce a net reduction in late cardiac disease. Further studies on dexrazoxane are warranted to confirm whether its role in reducing cardiac toxic effects is maintained long term. These findings suggest that survivorship follow-up guidelines should be refined to align with the risks associated with treatment.

Cardiac Morbidity and Mortality in Patients with Sarcoma: A Population-Based Study.

Soft tissue sarcoma (STS) is a rare malignancy that affects soft tissues. It encompasses various subtypes and requires different treatment strategies. Doxorubicin is a commonly used anthracycline in the management of localized and metastatic STS. However, high doses of doxorubicin are associated with cardiotoxicity, which can significantly impact patients' long-term outcomes. This study aimed to evaluate doxorubicin's effect on cardiac function in patients with sarcoma and to correlate the frequency of cardiotoxicity with potential risk factors. A retrospective analysis was conducted on patients with sarcoma who were treated with doxorubicin between 2016 and 2022 at King Abdulaziz Medical City in Saudi Arabia. Patient demographic information, comorbidities, cardiac measurements, laboratory values, systemic therapy, and treatment outcomes were collected from electronic medical records. A statistical analysis was performed to assess the association between cardiotoxicity and various factors. A total of 133 patients were included in the study, with a median age of 30 years. Cardiotoxicity was observed in 9% of the patients. Female patients had a significantly higher risk of developing cardiotoxicity. Patients with a higher Eastern Cooperative Oncology Group (ECOG) performance status and lower troponin I levels also had an increased risk of cardiotoxicity. However, there was no significant association between cardiotoxicity and the number of chemotherapy cycles, total cumulative dose of doxorubicin, or history of radiation. Furthermore, patients with cardiotoxicity had a higher risk of mortality. The overall survival of the patients was 18 months. Doxorubicin-associated cardiotoxicity is a concern for patients with sarcoma. Female patients and patients with a higher ECOG performance status are at an increased risk of developing cardiotoxicity. Careful monitoring and risk assessment are crucial for mitigating the adverse effects of doxorubicin treatment in patients with sarcoma. Future studies are warranted to validate these findings and explore preventive strategies for doxorubicin-induced cardiotoxicity in patients with sarcoma.

Progression-Free Survival (PFS) and Toxicity with Nivolumab-AVD Compared to Brentuximab Vedotin-AVD in Pediatric Advanced Stage (AS) Classic Hodgkin Lymphoma (cHL), Results of SWOG S1826

Background: Approaches to therapy in pediatric and adult cHL have differed historically. Brentuximab vedotin (BV) is efficacious in pediatric patients (pts) with high-risk cHL when combined with chemotherapy and response based involved site radiation therapy (RT) ( Castellino. NEJM 2022). Inhibition of the PD-1 pathway, central to the pathogenesis of cHL, is safe and effective in children with relapsed HL but has not been evaluated in the frontline setting. Led by SWOG, the National Clinical Trials Network (NCTN) conducted the randomized, phase 3 trial S1826 to evaluate nivolumab (N)-AVD vs BV-AVD in pts ages ≥12 years (y) with newly diagnosed Stage 3-4 cHL. Methods: Eligible pts were randomized 1:1 to either 6 cycles of N-AVD or BV-AVD. At randomization enrollment was stratified by age, International Prognostic Score (IPS), and intent to use RT. Treating site of pts 12-17y, the subject of this subgroup analysis, declared intent to use RT for residual metabolically active lesions on the end of treatment PET per protocol. Recipients of BV-AVD were required to receive G-CSF prophylaxis vs optional with N-AVD. Dexrazoxane was permitted, but not mandated. Response and disease progression was assessed by investigators using the 2014 Lugano Classification. The primary endpoint was PFS; secondary endpoints included overall survival (OS), event-free survival (EFS), and safety. Results: Of 976 eligible pts enrolled (from 7/9/2019 to 10/5/2022): 24.3% (n=237) were 12-17 y and randomized to N-AVD (n=120) or BV-AVD (n=117). Median age was 15.6 y (range, 12-17.9 y), 50% of pts were male, 69% were white, 15% were black, and 18% were Hispanic. 27% had an IPS score 4-7. At the 2nd interim analysis (50% of total PFS events) the SWOG Data and Safety Monitoring Committee recommended reporting the primary results as the primary PFS endpoint crossed the protocol-specified conservative statistical boundary for the full trial. In the pediatric cohort, 6 PFS events were observed after N-AVD compared to 12 events after BV-AVD. At a median follow-up of 12.1 months, the PFS was compared between arms [HR 0.48, 95% CI 0.18-1.28, stratified one-sided logrank p=0.067) in the pediatric cohort; 1 y PFS: N-AVD, 94%, BV-AVD, 88% (Fig.1). There have been no deaths in this age group. Overall use of RT was 0.8% (2/237) and 79% of pediatric pts received dexrazoxane. The rate of grade (gr) ≥ 3 hematologic adverse events (AE) was 45% after N-AVD compared to 41% after BV-AVD, with 3% gr ≥ 3 febrile neutropenia and 1% with sepsis after either regimen, despite differences in GCSF use (59.2% N, 93.2% BV). Overall rates of immune related AEs (irAEs) (any gr) were low: pneumonitis (3.0% N vs 1% BV), and colitis (0% N vs 1% BV). Rash (any gr) was more common in BV-AVD (2% N vs 14% BV). Hypo/hyperthyroidism (any gr) was higher after N-AVD (2% N vs 0% BV). Rates of transaminitis were similar (ALT elevation: 42% N vs 54% BV). While sensory peripheral neuropathy was more frequent after BV-AVD (sensory: 18% N vs 29% BV; motor: 8% N vs 5% BV), only 1% was &amp;gt; grade 3. Discontinuation of N vs BV therapy occurred in 8.3% vs 2.6% of pediatric pts respectively, compared to 7.9% vs 21.1% of adults. Conclusions: In early follow-up, N-AVD and BV-AVD are well tolerated and associated with low rates of irAEs in pts ages 12-17 y. With 12.1 mos median follow-up the PFS benefit observed for N-AVD in pediatric pts mirrors that observed in the overall study. RT usage is lower, and cumulative doxorubicin dose is higher than historical pediatric cHL trials. The difference in rate of discontinuation between study arms and by age group needs further evaluation. Longer follow-up is needed to better define the roles of N-AVD and Bv-AVD for AS cHL. S1826 is a model NCTN trial, providing earlier access to novel agents and harmonization of treatment for adolescents and young adults with AS cHL. Funding: NIH/NCI/NCTN grants U10CA180888 and U10CA180819, U10CA180820, U10CA180821, U10CA180863, U10 CA180886; and Bristol-Myers Squibb. Bv provided by Seagen (Canada Only). Clinical Trial NCT03907488.

Cardiac safety of pegylated liposomal doxorubicin after conventional doxorubicin exposure in patients with sarcoma and breast cancer.

388 Background: Lifetime cumulative doses of conventional doxorubicin (&gt;450 mg/m2) are associated with dose-dependent cardiotoxicity. In soft tissue sarcoma (STS) and breast cancer, conventional doxorubicin is often utilized in earlier lines of therapy, whereas pegylated liposomal doxorubicin (PLD) is typically reserved for recurrent and metastatic disease. PLD is associated with less cardiotoxicity than conventional doxorubicin and high doses of PLD can be administered without increased risk of cardiotoxicity in patients without prior exposure to conventional doxorubicin. Limited data exists evaluating cardiotoxicity associated with PLD treatment after conventional doxorubicin, especially when doxorubicin lifetime doses approach the established cumulative total lifetime dose of 450-550 mg/m2. This study aims to evaluate the cardiac safety of PLD use in patients who had prior exposure to conventional doxorubicin. Methods: This was a single-center, observational, retrospective cohort study conducted in patients ≥18 years with STS or breast cancer, who were exposed to conventional doxorubicin from an earlier line of treatment prior to PLD between January 2010 – May 2022. Patients participating in clinical trials were excluded. The primary outcome of the study was cardiac safety. Cardiac toxicity was defined as ≥ 10% decrease in left ventricle ejection fraction (LVEF) or new diagnosis of heart failure within 6 months after PLD cessation. Results: 494 patients were screened and 50 patients met inclusion criteria, 8 STS and 42 breast cancer patients. Median lifetime cumulative conventional doxorubicin dose in patients with STS was 450 mg/m2 with a max dose of 825 mg/m2, and 240 mg/m2 with a max dose of 300 mg/m2 in breast cancer patients. Median lifetime cumulative PLD dose was 105 mg/m2 (range: 35-150 mg/m2) in the STS group and 105 mg/m2 (range: 35-510 mg/m2) in the breast cancer group. A decrease of ≥ 10% in LVEF was not observed in the STS group. 22 breast cancer patients had available LVEF data on PLD; 3 of these patients experienced ≥ 10% in LVEF drop and one of three patients was diagnosed heart failure. The average cumulative dose of PLD administered in patients with &gt; 10% decrease in LVEF was 177 mg/m2 and had an average of 3.5 cycles. Most of STS patients initiated PLD treatment within 2 years after conventional doxorubicin while most breast patients initiated PLD treatment at least 10 years following conventional doxorubicin exposure. Conclusions: PLD administration in patients with prior exposure to conventional doxorubicin appears to be safe with limited cardiotoxicity in patients with STS and breast cancer. Future research is needed to determine if and how often routine cardiac monitoring is needed for patients on PLD without existing cardiac risk.

Cardiac Safety of Pegylated Liposomal Doxorubicin After Conventional Doxorubicin Exposure in Patients With Sarcoma and Breast Cancer.

Lifetime cumulative doses of conventional doxorubicin (>450 mg/m2) are associated with dose-dependent cardiotoxicity. In sarcoma and breast cancer, conventional doxorubicin is often utilized in the adjuvant setting, whereas pegylated liposomal doxorubicin (PLD) is typically reserved for recurrent and metastatic disease. PLD is believed to be associated with reduced cardiotoxicity compared to conventional doxorubicin.Limited data exists evaluating the cardiotoxicity associated with PLD treatment after conventional doxorubicin, especially when doxorubicin lifetime doses approach the established cumulative total lifetime dose of 450-550 mg/m2. This study aims to further qualify the cardiac safety of PLD use in patients who have had prior exposure to conventional doxorubicin. This was a single-center, observational, retrospective cohort study conducted in patients ≥18 years with sarcoma or breast cancer who were exposed to conventional doxorubicin from an earlier line of treatment before PLD between January 2010 to May 2022. Patients were evaluated for the presence of cardiac toxicity at any point in their treatment course. Cardiac toxicity was defined as ≥ 10% decrease in left ventricle ejection fraction (LVEF) or a new diagnosis of heart failure within six months after PLD cessation. The time interval between the last conventional doxorubicin exposure and PLD initiation and the time interval between PLD initiation and LVEF monitoring were also analyzed. 494 patients were screened, and 50 met inclusion criteria: eight with sarcoma and 42 with breast cancer. The median lifetime cumulative conventional doxorubicin dose in patients with sarcoma was 450 mg/m2 with a maximum dose of 825 mg/m2and 240 mg/m2 with a maximum dose of 300 mg/m2in breast cancer patients. The median lifetime cumulative PLD dose was 105 mg/m2(range: 35-150 mg/m2) in the sarcoma group and 105 mg/m2(range: 35-510 mg/m2) in the breast cancer group. A decrease of ≥ 10% in LVEF was not observed in the sarcoma group. Patients with breast cancer had available LVEF data on PLD, and three of these patients experienced ≥ 10% in LVEF drop, with one of these patients diagnosed with heart failure. The average cumulative dose of PLD administered in patients with > 10% decrease in LVEF was 177 mg/m2 and had an average of 3.5 cycles. Five sarcoma patients initiated PLD treatment within two years after conventional doxorubicin exposure, while most breast patients initiated PLD treatment at least 10 years following conventional doxorubicin exposure. The average time from PLD initiation to first and second available LVEF monitoring was one and five months in the sarcoma group and three and eight months in the breast cancer group, respectively. PLD administration in patients with prior exposure to conventional doxorubicin appears to be safe, with limited cardiotoxicity in patients with sarcoma and breast cancer. Future research is needed to determine if and how often routine cardiac monitoring is needed for patients on PLD without existing cardiac risk.

The role of inflammation and antioxidant defenses in the cardiotoxicity of doxorubicin in elderly CD-1 male mice

Doxorubicin (DOX) is a potent chemotherapeutic agent used against several cancer types. However, due to its cardiotoxic adverse effects, the use of this drug may be also life-threatening. Although most cancer patients are elderly, they are poorly represented and evaluated in pre-clinical and clinical studies. Considering this, the present work aims to evaluate inflammation and oxidative stress as the main mechanisms of DOX-induced cardiotoxicity, in an innovative approach using an experimental model constituted of elderly animals treated with a clinically relevant human cumulative dose of DOX. Elderly (18–20 months) CD-1 male mice received biweekly DOX administrations, for 3 weeks, to reach a cumulative dose of 9.0 mg/kg. One week (1W) or two months (2 M) after the last DOX administration, the heart was collected to determine both drug’s short and longer cardiac adverse effects. The obtained results showed that DOX causes cardiac histological damage and fibrosis at both time points. In the 1W-DOX group, the number of nuclear factor kappa B (NF-κB) p65 immunopositive cells increased and a trend toward increased NF-κB p65 expression was seen. An increase of inducible nitric oxide synthase (iNOS) and interleukin (IL)-33 and a trend toward increased IL-6 and B-cell lymphoma-2-associated X (Bax) expression were seen after DOX. In the same group, a decrease in IL-1β, p62, and microtubule-associated protein 1A/1B-light chain 3 (LC3)-I, p38 mitogen-activated protein kinase (MAPK) expression was observed. Contrariwise, the animals sacrificed 2 M after DOX showed a significant increase in glutathione peroxidase 1 and Bax expression with persistent cardiac damage and fibrosis, while carbonylated proteins, erythroid-2-related factor 2 (Nrf2), NF-κB p65, myeloperoxidase, LC3-I, and LC3-II expression decreased. In conclusion, our study demonstrated that in an elderly mouse population, DOX induces cardiac inflammation, autophagy, and apoptosis in the heart in the short term. When kept for a longer period, oxidative-stress-linked pathways remained altered, as well as autophagy markers and tissue damage after DOX treatment, emphasizing the need for continuous post-treatment cardiac monitoring.

Subsequent female breast cancer risk associated with anthracycline chemotherapy for childhood cancer

Anthracycline-based chemotherapy is associated with increased subsequent breast cancer (SBC) risk in female childhood cancer survivors, but the current evidence is insufficient to support early breast cancer screening recommendations for survivors treated with anthracyclines. In this study, we pooled individual patient data of 17,903 survivors from six well-established studies, of whom 782 (4.4%) developed a SBC, and analyzed dose-dependent effects of individual anthracycline agents on developing SBC and interactions with chest radiotherapy. A dose-dependent increased SBC risk was seen for doxorubicin (hazard ratio (HR) per 100 mg m−2: 1.24, 95% confidence interval (CI): 1.18–1.31), with more than twofold increased risk for survivors treated with ≥200 mg m−2 cumulative doxorubicin dose versus no doxorubicin (HR: 2.50 for 200–299 mg m−2, HR: 2.33 for 300–399 mg m−2 and HR: 2.78 for ≥400 mg m−2). For daunorubicin, the associations were not statistically significant. Epirubicin was associated with increased SBC risk (yes/no, HR: 3.25, 95% CI: 1.59–6.63). For patients treated with or without chest irradiation, HRs per 100 mg m−2 of doxorubicin were 1.11 (95% CI: 1.02–1.21) and 1.26 (95% CI: 1.17–1.36), respectively. Our findings support that early initiation of SBC surveillance may be reasonable for survivors who received ≥200 mg m−2 cumulative doxorubicin dose and should be considered in SBC surveillance guidelines for survivors and future treatment protocols.

Clonal Hematopoiesis as a Molecular Risk Factor for Doxorubicin-Induced Cardiotoxicity: A Proof-of-Concept Study.

The main dose-limiting toxicity of anthracyclines is cardiotoxicity. Clonal hematopoiesis (CH), somatic mutations in hematopoietic stem or progenitor cells in patients without hematologic malignancy, is also associated with risk for adverse cardiovascular events and worse outcomes overall. We hypothesize that CH increases risk for doxorubicin-induced cardiotoxicity (DIC). We conducted a retrospective cohort study in patients treated with doxorubicin for cancer (N = 100). Patients (n = 25) had incident symptomatic heart failure, decline in left ventricular ejection fraction, or arrhythmia. CH was identified using paired peripheral blood and tumor DNA. After adjusting for age at doxorubicin initiation, diabetes, dyslipidemia, and chest radiation, high cumulative dose of doxorubicin (>240 mg/m2; odds ratio [OR], 7.00; 95% CI, 1.77 to 27.74; P = .0056), CH (OR, 8.58; 95% CI, 2.05 to 35.99; P = .0033), and history of smoking (OR, 3.15; 95% CI, 1.00 to 9.93; P = .0495) were associated with DIC. This study provides preliminary evidence for CH as a predictive risk factor for DIC, which, with further investigation, could serve as an important precision medicine biomarker for the large number of patients with cancer who have CH.

Neopetroside-B alleviates doxorubicin-induced cardiotoxicity via mitochondrial protection

Doxorubicin, a member of the anthracycline family, is a widely prescribed anticancer chemotherapy drug. Unfortunately, cumulative doses of doxorubicin can cause mitochondrial dysfunction, leading to acute or chronic cardiotoxicity. This study demonstrated that Neopetroside-B (NPS-B) protects cardiomyocytes in the presence of doxorubicin. NPS-B improved mitochondrial function in cardiomyocytes by increasing ATP production and oxygen consumption rates. On the other hand, NPS-B negatively influenced cancer cell lines by increasing reactive oxygen species. We analyzed NPS-B-influenced metabolites (VIP > 1.0; AUC>0.7; p < 0.05) and proteins (FC > 2.0) and constructed metabolite-protein enrichment, which showed that NPS-B affected uracil metabolism and NAD-binding proteins (e.g., aldehyde dehydrogenase and glutathione reductase) in cardiomyocytes. However, for the cancer cells, NPS-B decreased the NAD+/NADH balance, impairing cell viability. In a xenograft mouse model treated with doxorubicin, NPS-B reduced cardiac fibrosis and improved cardiac function. NPS-B may be a beneficial intervention to reducing doxorubicin-induced cardiotoxicity with anticancer effects.

Doxorubicin Dose-Dependent Impact on Physiological Balance-A Holistic Approach in a Rat Model.

Doxorubicin (DOX) is commonly used in several chemotherapies to treat various cancers, but it is known to cause cardiotoxicity and cardiac symptoms. Autonomic dysfunction is thought to contribute to the cardiotoxic effects of DOX, but the specific dose required to disrupt homeostatic processes is still unclear and is influenced by numerous factors. This study aimed to investigate how the DOX dosage affects autonomic function and physiological parameters, to elucidate the neurocardiac mechanisms underlying the observed cardiovascular side effects. Wistar rats were treated with DOX for four weeks and divided into three dosing groups: DOX8 (2 mg/kg/week), DOX16 (4 mg/kg/week), and DOX20 (5 mg/kg/week). A control group received NaCl 0.9% saline (1 mL/kg/week). In an acute experiment, we recorded blood pressure (BP), electrocardiogram, heart rate (HR), and respiratory rate (RF). Baroreflex gain and chemoreflex sensitivity were calculated, and cardiac tissue was analyzed with picrosirius histochemistry to measure collagen content. Our results showed that the LF/HF ratio, indicative of autonomic activity, was altered along with hypotension and bradycardia at a cumulative DOX dose threshold of 16 mg/kg. We observed a positive correlation between DOX dose and BP, HR, urinary norepinephrine, LF/HF ratio, and fibrotic heart area. Lower LF/HF ratios were associated with high DOX doses, reflecting drug-induced impairment of autonomic control of HR. This study provides valuable insights into the dose-dependent effects of DOX on physiological parameters and the development of cardiovascular dysfunction. These findings are critical, which is important for optimizing the management and therapeutic strategies for patients undergoing DOX-based chemotherapy.

Substrate oxidation during exercise in childhood acute lymphoblastic leukemia survivors

Children with acute lymphoblastic leukemia (ALL) are at high risk of developing long-term cardiometabolic complications during their survivorship. Maximal fat oxidation (MFO) is a marker during exercise of cardiometabolic health, and is associated with metabolic risk factors. Our aim was to characterize the carbohydrate and fat oxidation during exercise in childhood ALL survivors. Indirect calorimetry was measured in 250 childhood ALL survivors to quantify substrate oxidation rates during a cardiopulmonary exercise test. A best-fit third-order polynomial curve was computed for fat oxidation rate (mg/min) against exercise intensity (O2peak) and was used to determine the MFO and the peak fat oxidation (Fatmax). The crossover point was also identified. Differences between prognostic risk groups were assessed (ie, standard risk [SR], high risk with and without cardio-protective agent dexrazoxane [HR + DEX and HR]). MFO, Fatmax and crossover point were not different between the groups (p = .078; p = .765; p = .726). Fatmax and crossover point were achieved at low exercise intensities. A higher MFO was achieved by men in the SR group (287.8 ± 111.2 mg/min) compared to those in HR + DEX (239.8 ± 97.0 mg/min) and HR groups (229.3 ± 98.9 mg/min) (p = .04). Childhood ALL survivors have low fat oxidation during exercise and oxidize carbohydrates at low exercise intensities, independently of the cumulative doses of doxorubicin they received. These findings alert clinicians on the long-term impact of cancer treatments on childhood ALL survivors’ substrate oxidation.

Left ventricular response to short exercise in long term non-hodgkin lymphoma survivors

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Echocardiographic left ventricular (LV) global longitudinal strain (GLS) may be used to detect subclinical ventricular dysfunction in patients who have received cardiotoxic chemotherapy. However, in some persons participating in recreational sports, GLS at rest may be lower than normal, but normalizes after a short exercise test as soon as resting heart rate (HR) is reached. The aim of the study was to determine GLS response to a short exercise test in patients treated for aggressive non- Hodgkin Lymphoma (NHL) compared to controls. Methods We conducted a cross-sectional study nested in a cohort of NHL survivors and their siblings served as controls . Survivors were treated 5 years ago or longer with a cumulative doxorubicin (anthracycline) dose of at least 250 mg/m2. Transthoracic Echocardiography (TTE) was performed according to the guidelines. First, GLS and LV ejection fraction (EF) were measured at rest. After 20 squats, GLS and EF measurements were repeated when the HR was comparable to the HR during rest measurements. Results In total 20 survivors (mean age 49 (± 13) years, 11 men (55%) were included and measurements were compared to 14 controls. (mean age 45 (± 8) years, 8 men ( 57 %). In patients at rest, the EF was 52.6% ( ± 8.0%) and the GLS −16.1% ( ± 2.9%), compared to controls with an EF of 56.2% (± 3.4% ) (p-value 0.13) and GLS −18.0% (± 1.4 %) (p-value 0.031). All patients performed 20 squats and their EF increased to 55.0% (± 6.8%) and GLS −18.7% (± 3.8%) compared to controls in whom the EF increased to 62% (± 4.7%) (p-value 0.002) and GLS −21.3% (± 2.5%) (p-value 0.037) (Figure 1). Conclusion In addition to GLS measurement at rest, GLS after a short exercise test seems to be a promising tool to detect subclinical LV dysfunction in non-Hodgkin Lymphoma survivors. Further research in larger studies is needed to confirm these findings and to assess the association with clinical parameters.