Multivariable regression analysis of febrile neutropenia occurrence in early breast cancer patients receiving chemotherapy assessing patient-related, chemotherapy-related and genetic risk factors

Development of a Machine Learning-Based Prediction Model for Chemotherapy-Induced Myelosuppression in Children with Wilms' Tumor

Purpose: Develop and validate an accessible prediction model using machine learning (ML) to predict the risk of chemotherapy-induced myelosuppression (CIM) in children with Wilms' tumor (WT) before chemotherapy is administered, enabling early preventive management. Methods: A total of 1433 chemotherapy cycles in 437 children with WT who received chemotherapy in our hospital from January 2009 to March 2022 were retrospectively analyzed. Demographic data, clinicopathological characteristics, hematology and blood biochemistry baseline results, and medication information were collected. Six ML algorithms were used to construct prediction models, and the predictive efficacy of these models was evaluated to select the best model to predict the risk of grade ≥ 2 CIM in children with WT. A series of methods, such as the area under the receiver operating characteristic curve (AUROC), the calibration curve, and the decision curve analysis (DCA) were used to test the model's accuracy, discrimination, and clinical practicability. Results: Grade ≥ 2 CIM occurred in 58.5% (839/1433) of chemotherapy cycles. Based on the results of the training and validation cohorts, we finally identified that the extreme gradient boosting (XGB) model has the best predictive efficiency and stability, with an AUROC of up to 0.981 in the training set and up to 0.896 in the test set. In addition, the calibration curve and the DCA showed that the XGB model had the best discrimination and clinical practicability. The variables were ranked according to the feature importance, and the five variables contributing the most to the model were hemoglobin (Hgb), white blood cell count (WBC), alkaline phosphatase, coadministration of highly toxic chemotherapy drugs, and albumin. Conclusions: The incidence of grade ≥ 2 CIM was not low in children with WT, which needs attention. The XGB model was developed to predict the risk of grade ≥ 2 CIM in children with WT for the first time. The model has good predictive performance and stability and has the potential to be translated into clinical applications. Based on this modeling and application approach, the extension of CIM prediction models to other pediatric malignancies could be expected.

Impact of baseline telomere length on survival and chemotherapy related toxicity in breast cancer patients receiving (neo)adjuvant anthracycline containing chemotherapy

PURPOSE

The aim of this study is to assess baseline mean leukocyte telomere length (TL) as a potential predictive factor for chemotherapy toxicity and a prognostic marker for long-term outcome in early breast cancer (BC) patients.

METHODS

445 BC patients were selected, diagnosed between 2007 and 2010 with early BC and treated with (neo)adjuvant fluorouracil, epirubicin and cyclophosphamide (FEC) or with FEC and Docetaxel (FEC-D). RT-qPCR was performed on germline DNA samples collected at diagnosis before any treatment, to measure mean leukocyte TL. Uni- and multivariable logistic regression or Cox proportional hazard regression analyses were carried out to assess correlation between baseline TL and toxicity parameters (derived from the medical chart) or longer-term outcome.

RESULTS

Baseline TL correlated with age as expected (p = 0.005), but not with febrile neutropenia (n = 97), left ventricular ejection fraction >10% decrease (n = 17) nor other toxicity endpoints measured (all p > 0.05). TL was neither associated with overall survival, breast cancer specific survival or distant disease-free survival (all p > 0.05).

CONCLUSIONS

Baseline TL is not associated with chemotherapy-related toxicity nor long-term outcome in BC patients.

Identification of Two Genetic Loci Associated with Leukopenia after Chemotherapy in Patients with Breast Cancer

PURPOSE

To identify molecular predictors of grade 3/4 neutropenic or leukopenic events (NLE) after chemotherapy using a genome-wide association study (GWAS).

EXPERIMENTAL DESIGN

A GWAS was performed on patients in the phase III chemotherapy study SUCCESS-A (n = 3,322). Genotyping was done using the Illumina HumanOmniExpress-12v1 array. Findings were functionally validated with cell culture models and the genotypes and gene expression of possible causative genes were correlated with clinical treatment response and prognostic outcomes.

RESULTS

One locus on chromosome 16 (rs4784750; NLRC5; P = 1.56E-8) and another locus on chromosome 13 (rs16972207; TNFSF13B; P = 3.42E-8) were identified at a genome-wide significance level. Functional validation revealed that expression of these two genes is altered by genotype-dependent and chemotherapy-dependent activity of two transcription factors. Genotypes also showed an association with disease-free survival in patients with an NLE.

CONCLUSIONS

Two loci in NLRC5 and TNFSF13B are associated with NLEs. The involvement of the MHC I regulator NLRC5 implies the possible involvement of immuno-oncological pathways.

Improved risk prediction of chemotherapy-induced neutropenia-model development and validation with real-world data

BACKGROUND

The existing risk prediction models for chemotherapy-induced febrile neutropenia (FN) do not necessarily apply to real-life patients in different healthcare systems and the external validation of these models are often lacking. Our study evaluates whether a machine learning-based risk prediction model could outperform the previously introduced models, especially when validated against real-world patient data from another institution not used for model training.

METHODS

Using Turku University Hospital electronic medical records, we identified all patients who received chemotherapy for non-hematological cancer between the years 2010 and 2017 (N = 5879). An experimental surrogate endpoint was first-cycle neutropenic infection (NI), defined as grade IV neutropenia with serum C-reactive protein >10 mg/l. For predicting the risk of NI, a penalized regression model (Lasso) was developed. The model was externally validated in an independent dataset (N = 4594) from Tampere University Hospital.

RESULTS

Lasso model accurately predicted NI risk with good accuracy (AUROC 0.84). In the validation cohort, the Lasso model outperformed two previously introduced, widely approved models, with AUROC 0.75. The variables selected by Lasso included granulocyte colony-stimulating factor (G-CSF) use, cancer type, pre-treatment neutrophil and thrombocyte count, intravenous treatment regimen, and the planned dose intensity. The same model predicted also FN, with AUROC 0.77, supporting the validity of NI as an endpoint.

CONCLUSIONS

Our study demonstrates that real-world NI risk prediction can be improved with machine learning and that every difference in patient or treatment characteristics can have a significant impact on model performance. Here we outline a novel, externally validated approach which may hold potential to facilitate more targeted use of G-CSFs in the future.

Prospective external validation of an updated algorithm to quantify risk of febrile neutropenia in cancer patients after a cycle of chemotherapy

PURPOSE

Febrile neutropenia resulting from chemotherapy is a significant cause of morbidity and mortality in cancer patients. We had previously published the associates of the risk of febrile neutropenia, and this study now extends and modifies the previous model as well as tests its external validity.

METHODS

We have recruited documented febrile neutropenia cases with solid tumors, in addition to a selected control group of cancer patients from one institution treated between 2015 and 2019. We then united our sample with our previously published original derivation group, to modify and update our previous model by logistic regression analysis. Additionally, consecutive cancer patients from 5 institutions were recruited in 2020 to test external validity of the resultant algorithm.

RESULTS

A total of 4075 cycles of chemotherapy in 1282 cases were recruited in the updated, new model derivation group, and a total of 8 variables were selected for the updated algorithm. In the new external validation group, 653 cycles of chemotherapy in 624 patients were analyzed, to indicate that after cycles without prophylactic granulocyte colony-stimulating factor (GCSF) usage, the algorithm yielded a sensitivity value of 91%, specificity of 40%, and an area under curve (AUC) figure of 0.78, when a risk cutoff threshold value of ≥ 0.20 is chosen. This algorithm is now embedded in a web application for free clinical use.

CONCLUSION

Our algorithm identifies and quantifies the risk of febrile neutropenia in cancer patients. Further studies are required to improve this model with additional predictors.

Risk factors for severe neutropenia in pancreatic cancer patients treated with gemcitabine/nab-paclitaxel combination therapy

AIM

Combination therapy with gemcitabine and nanoparticle albumin-bound paclitaxel (nab-paclitaxel), known as GnP therapy, significantly prolongs the survival of pancreatic cancer patients compared with gemcitabine monotherapy. However, it may cause severe neutropenia, requiring discontinuation of treatment. This study aimed to clarify the risk factors for Grade 3/4 neutropenia during GnP therapy.

METHODS

Clinical data of pancreatic cancer patients who underwent GnP therapy at the Cancer Institute Hospital of the Japanese Foundation for Cancer Research from December 2014 to December 2016 were retrospectively collected. The relationship of Grade 3/4 neutropenia onset to laboratory values and patient background factors was investigated by multivariate logistic regression analysis.

RESULTS

Clinical data of 222 patients were analyzed. Grade 3/4 neutropenia occurred in 118 patients (53.2%) in the first cycle of GnP therapy. Multivariate analysis identified low absolute neutrophil count (ANC), high total bilirubin (T-Bil), and low C-reactive protein (CRP) as risk factors for Grade 3/4 neutropenia. Age was not a risk factor. The incidence of neutropenia was 85.7% in patients with all three risk factors, but only 27.7% in patients with none of them.

CONCLUSION

Low ANC, high T-Bil, and low CRP may be risk factors for Grade 3/4 neutropenia in patients receiving GnP therapy, even if these laboratory values are within normal reference ranges. Patients with these risk factors should be carefully monitored for adverse events.

Clinical and genetic risk factors for the prediction of hepatotoxicity induced by a docetaxel, epirubicin and cyclophosphamide regimen in breast cancer patients

Aim: To screen clinical and genetic risk factors and examine their combined effect on docetaxel, epirubicin and cyclophosphamide (TEC) regimen-induced liver injury (TEC-ILI). Patients & methods: We enrolled 396 breast cancer patients, and TEC-ILI-associated factors were screened by logistic regression analyses. Results: SOD2 rs4880 and ABCG2 rs2231142 polymorphisms correlated with an increased risk of TEC-ILI. Multivariate analysis incorporating clinical and genetic factors revealed that ABCC1 rs246221 (CC) and SOD2 rs4880 (AG/GG) increased the risk of TEC-ILI. Patients with at least two risk factors among nonalcoholic fatty liver disease, high low-density lipoproteinemia levels and the rs246221 or rs4880 adverse genotypes exhibited a significantly increased risk of developing TEC-ILI. Conclusion: The combination of clinical and genetic risk factors had higher predictive value for TEC-ILI than the interclinical risk factors alone.

Role of Genetic Variation in ABC Transporters in Breast Cancer Prognosis and Therapy Response

Breast cancer is the most common cancer in women in the world. The role of germline genetic variability in ATP-binding cassette (ABC) transporters in cancer chemoresistance and prognosis still needs to be elucidated. We used next-generation sequencing to assess associations of germline variants in coding and regulatory sequences of all human ABC genes with response of the patients to the neoadjuvant cytotoxic chemotherapy and disease-free survival (n = 105). A total of 43 prioritized variants associating with response or survival in the above testing phase were then analyzed by allelic discrimination in the large validation set (n = 802). Variants in ABCA4, ABCA9, ABCA12, ABCB5, ABCC5, ABCC8, ABCC11, and ABCD4 associated with response and variants in ABCA7, ABCA13, ABCC4, and ABCG8 with survival of the patients. No association passed a false discovery rate test, however, the rs17822931 (Gly180Arg) in ABCC11, associating with response, and the synonymous rs17548783 in ABCA13 (survival) have a strong support in the literature and are, thus, interesting for further research. Although replicated associations have not reached robust statistical significance, the role of ABC transporters in breast cancer should not be ruled out. Future research and careful validation of findings will be essential for assessment of genetic variation which was not in the focus of this study, e.g., non-coding sequences, copy numbers, and structural variations together with somatic mutations.

Impact of variants in ATP-binding cassette transporters on breast cancer treatment

There has been substantial interest in the impact of ATP-binding cassette (ABC) transporter variability on breast cancer drug resistance. Here, we provide a systematic review of ABC variants in breast cancer therapy. Notably, most studies used small heterogeneous cohorts and their identified associations lack statistical stringency, replication and mechanistic support. We conclude that commonly studied ABC polymorphisms are not suitable to accurately predict therapy response or toxicity in breast cancer patients and cannot guide treatment decisions. However, recent research shows that ABC transporters harbor a plethora of rare variants with individually small effect sizes, and we argue that a shift in strategy from target variant interrogation to comprehensive profiling might hold promise to drastically improve the predictive power of outcome models.

Clinical application of the AUC-guided dosage adjustment of docetaxel-based chemotherapy for patients with solid tumours: a single centre, prospective and randomised control study

BACKGROUND

Docetaxel (DTX) is a widely used anti-tumour drug, and its dosage is solely determined by body surface area (BSA). Adverse events, such as neutropenia or unsatisfied efficacy, likely occur because of differences in the pharmacokinetics (PK) and pharmacodynamics of patients. Thus, a feasible dosage adjustment method is needed.

METHODS

A total of 209 eligible patients who provided consent were enrolled and randomised into two groups to receive the BSA- and PK-guided dosage adjustments of DTX-based chemotherapy (3 weeks per cycle). The AUC of DTX was detected, and the therapeutic window for Chinese patients was determined. The proportion of patients within the therapeutic window was evaluated. Neutropenia was examined in accordance with the toxicity grading standard suggested by the World Health Organisation. Tumour response was assessed in accordance with Response Evaluation Criteria in Solid Tumors version 1.1. The primary endpoint was the incidence of neutropenia, and the secondary endpoints were disease control rate (DCR) and 3-year survival rate.

RESULTS

The therapeutic window for Chinese patients was 1.7-2.5 mg·h/L. The proportion of patients within the therapeutic window was 63.89% versus 28.33% (P < 0.0001), and the incidence of neutropenia was 68.33% versus 38.89% (P = 0.001) in the experimental group versus the control group in the sixth cycle, respectively. DCR was 72% versus 85% (P = 0.018) in the control group versus the experimental group. The 3-year survival rate of the PK group was significantly higher than that of the BSA group (P = 0.034).

CONCLUSIONS

The PK-guided dosage adjustment of DTX could significantly increase the proportion of patients within the therapeutic window, decrease the incidence of neutropenia and increase the DCR and the 3-year survival rate. The PK-guided dosage adjustment based on the dynamic monitoring of AUC could be a useful method for oncologists to improve individualised treatment options, optimise drug efficacy and reduce drug toxicity.

Patient factors and their impact on neutropenic events: a systematic review and meta-analysis

BACKGROUND

Neutropenia is associated with an increased risk of mortality and hospitalisation. Strategies, including the prescribing of colony-stimulating growth factors (CSFs), are adopted when a high risk (> 20%) of neutropenic complications are seen in the clinical trial setting. With a diverse treatment population that may differ from the patient groups recruited to studies, appropriate prescribing decisions by clinicians are essential. At present, results are conflicting from studies evaluating the risks of certain patient attributes on neutropenic events; we aimed to aggregate these associations to guide future management.

DESIGN

A systematic review with a meta-analysis was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement. Studies were identified through a literature search using MEDLINE, EMBASE and Cumulative Index to Nursing and Allied Health Literature (CINAHL) databases from inception to December 1, 2017. Studies were included into a meta-analysis if they adjusted for confounders; analyses were conducted in STATA v 15.1 SE.

RESULTS

A total of 4415 articles were retrieved by the search with 37 meeting the inclusion criteria and 12 eligible for meta-analysis. Meta-analysis was conducted for increasing age and yielded a pooled odds ratio of 1.39 (1.11, 1.76, I2 = 24.1%), in our subgroup analysis of 4814 patients. Odds ratios for studies were pooled that reported associations for one co-morbidity compared to none and resulted in an overall odds of 1.54 (CI 1.09-2.09, I2 = 13.1%), including 9189 patients in total.

CONCLUSIONS

Results can enhance current guidance in prescribing primary prophylaxis for treatments that either fall marginally under the internationally recognised 20% neutropenia risk.

Risk factors for neutropenia and febrile neutropenia following prophylactic pegfilgrastim

AIM

Neutropenia is a common side effect of myelosuppressive chemotherapy. Administration of granulocyte colony-stimulating factor is being used for neutropenia prophylaxis, but there are patients who develop neutropenia or febrile neutropenia despite prophylaxis. We attempted to identify potential risk factors for chemotherapy-induced neutropenia in patients with pegfilgrastim prophylaxis.

METHODS

This was a single-center, retrospective, observational study of patients with breast cancer or diffuse large B-cell lymphoma. We obtained patients' data from electronic medical records, including baseline demographics and clinical characteristics regarding diseases, treatments and laboratory values. The outcome measures assessed were the incidence of neutropenia and febrile neutropenia.

RESULTS

There were a total of 127 patients, including 77 patients with diffuse large B-cell lymphoma (DLBCL) and 50 patients with breast cancer, and we analyzed 722 chemotherapy cycles. We found 88 cases (12.2%) of grade 3 or 4 neutropenia and 39 cases of febrile neutropenia (5.4%). In the univariate analysis, variables associated with both grade 3 or 4 neutropenia and febrile neutropenia were age, cancer type, cancer stage, radiotherapy and platelet count. A multivariate logistic regression model revealed that age, radiotherapy and platelet count were significant factors in severe neutropenia, whereas platelet count was the only statistically significant factor in febrile neutropenia. Platelet counts of less than 150 000/mm³ increased the risk of neutropenia and febrile neutropenia approximately fourfold. In the subgroup analysis of patients with DLBCL, it was found that platelet count was a significant factor for both neutropenia and febrile neutropenia.

CONCLUSION

Among cancer patients with pegfilgrastim prophylaxis, advanced age, absence of radiation therapy and low platelet count were independent predictors of neutropenia, and low platelet count was the predictor of febrile neutropenia.

The vertebral 3'-deoxy-3'-18F-fluorothymidine uptake predicts the hematological toxicity after systemic chemotherapy in patients with lung cancer

OBJECTIVES

Although hematological toxicities (HT) are the leading adverse events of systemic chemotherapy, the estimation of severe HT is challenging. Recently, 3'-deoxy-3'-[¹⁸F]-fluorothymidine (¹⁸F-FLT) accumulation with PET has been considered a biomarker of the cell proliferation. This study aims to elucidate whether the vertebral accumulation of ¹⁸F-FLT could estimate severe HT during platinum-doublet chemotherapy.

METHODS

In this Institutional Review Board-approved retrospective study, 50 patients with primary lung cancer underwent ¹⁸F-FLT PET scan before platinum-doublet chemotherapy. We evaluated the standardized uptake value, total vertebral proliferation (TVP), and TVP/body surface area (TVP/BSA) of the vertebral body (Th4, Th8, Th12, and L4), and then the associations between those parameters and frequency of severe HT during platinum-doublet chemotherapy were assessed.

RESULTS

Severe HT (grade 3/4) was observed in 40.0% of patients during the first cycle. The ROC curve analyses revealed that the TVP/BSA of L4 was the most discriminative parameter among PET parameters for the prediction of severe HT. The multivariate logistic regression analysis revealed the TVP/BSA of L4 (odds ratio [OR], 0.94; p = 0.0036) and the frequency of the grade 3/4 hematological toxicity in previous clinical trials (OR, 1.03; p = 0.023) were independent predictors. Furthermore, the sensitivity, specificity, and accuracy of the TVP/BSA of L4 cut-off of 68.7 to predict grade 3/4 HT were 80.0%, 86.7%, and 84.0%, respectively. A low TVP/BSA of L4 (< 68.7) as a binary variable was a significant indicator of severe HT (OR, 26.0; p = 0.000026).

CONCLUSIONS

The low ¹⁸F-FLT uptake in the lower vertebral body is a predictor of severe HT in patients with lung cancer who receive platinum-doublet chemotherapy.

TRIAL REGISTRATION

Trial registration: UMIN000027540 KEY POINTS: • The vertebral ¹⁸ F-FLT uptake with PET is an independent predictor of the severe hematological toxicity during the first cycle of platinum-doublet chemotherapy. • The ¹⁸ F-FLT uptake in L4 vertebral body estimated hematological toxicities better than that in the upper vertebra (Th4, Th8, and Th12). • The evaluation of the amount and activity of hematopoietic cells in the bone marrow cavity using ¹⁸ F-FLT PET imaging could provide predictive data of severe hematological toxicities and help determine an appropriate drug combination or dose intensity in patients with advanced malignant diseases.

Development of a simplified multivariable model to predict neutropenic complications in cancer patients undergoing chemotherapy

PURPOSE

Neutropenic complications remain the major dose-limiting toxicities of cancer chemotherapy. The aim of this study was to develop and internally validate a comprehensive and easily measurable scoring system for prediction of severe or febrile neutropenia in the first chemotherapy cycle of patients with solid tumors or lymphoma.

METHODS

This prospective cohort study included consecutive patients at a tertiary referral hospital. Many clinical and laboratory-independent variables were measured at baseline. A multivariable logistic regression analysis was applied after unadjusted analysis, and the multivariable model was transformed into a simplified risk score based on 6 bootstrapped regression coefficients. The simplified scoring system was internally validated using cross-validation. All statistical tests were two-sided.

RESULTS

A total of 305 patients were enrolled and followed during 1732 chemotherapy cycles. Of these, 259 were eligible for analysis. The multivariable model revealed 6 predictive factors for severe or febrile neutropenia (scores in parentheses): high-risk regimen without colony-stimulating factor (4 points), intermediate-risk regimen without colony-stimulating factor (3 points), age > 65 years and elevated ferritin (3 points), body mass index < 23 kg/m² and body surface area < 2 m² (2 points), estimated glomerular filtration rate < 60 mL/min/1.73m² (2 points), and elevated C-reactive protein (1 point). The receiver operating characteristic curve was 0.832 (95% confidence interval [Cl], 0.767-0.897) for the simplified model and 0.816 (95% Cl, 0.771-0.860) for the cross-validation.

CONCLUSIONS

We developed and internally validated a user-friendly prediction model to guide personalized decision-making using available clinical data and few cost-effective laboratory tests. External validation in other centers with different patients is required.

Independent replication of polymorphisms predicting toxicity in breast cancer patients randomized between dose-dense and docetaxel-containing adjuvant chemotherapy

Introduction

Although pharmacogenomics has evolved substantially, a predictive test for chemotherapy toxicity is still lacking. We compared the toxicity of adjuvant dose-dense doxorubicin-cyclophosphamide (ddAC) and docetaxel-doxorubicin-cyclophosphamide (TAC) in a randomized multicenter phase III trial and replicated previously reported associations between genotypes and toxicity.

Results

646 patients (97%) were evaluable for toxicity (grade 2 and higher). Whereas AN was more frequent after ddAC (P < 0.001), TAC treated patients more often had PNP (P < 0.001). We could replicate 2 previously reported associations: TECTA (rs1829; OR 4.18, 95% CI 1.84-9.51, P = 0.001) with PNP, and GSTP1 (rs1138272; OR 2.04, 95% CI 1.13-3.68, P = 0.018) with PNP.

Materials and methods

Patients with pT1-3, pN0-3 breast cancer were randomized between six cycles A60C600 every 2 weeks or T75A50C500 every 3 weeks. Associations of 13 previously reported single nucleotide polymorphisms (SNPs) with the most frequent toxicities: anemia (AN), febrile neutropenia (FN) and peripheral neuropathy (PNP) were analyzed using logistic regression models.

Conclusions

In this independent replication, we could replicate an association between 2 out of 13 SNPs and chemotherapy toxicities. These results warrant further validation in order to enable tailored treatment for breast cancer patients.

Clinical validation of genetic variants associated with in vitro chemotherapy-related lymphoblastoid cell toxicity

Hematotoxicity is one of the major side effects of chemotherapy. The aim of this study was to examine the association between single nucleotide polymorphisms (SNPs) and hematotoxicity in breast cancer patients in a subset of patients of the SUCCESS prospective phase III chemotherapy study. All patients (n = 1678) received three cycles of 5-fluorouracil, epirubicin, and cyclophosphamide (FEC) followed by three cycles of docetaxel or docetaxel/gemcitabine, depending on randomization. Germline DNA was genotyped for 246 SNPs selected from a previous genome-wide association study (GWAS) in a panel of lymphoblastoid cell lines, with gemcitabine toxicity as the phenotype. All SNPs were tested for their value in predicting grade 3 or 4 neutropenic or leukopenic events (NLEs). Their prognostic value in relation to overall survival and disease-free survival was also tested.

None of the SNPs was found to be predictive for NLEs during treatment with docetaxel/gemcitabine. Two SNPs in and close to the PIGB gene significantly improved the prediction of NLEs after FEC, in addition to the factors of age and body surface area. The top SNP (rs12050587) had an odds ratio of 1.38 per minor allele (95% confidence interval, 1.17 to 1.62). No associations were identified for predicting disease-free or overall survival.

Genetic variance in the PIGB gene may play a role in determining interindividual differences in relation to hematotoxicity after FEC chemotherapy.

Comparing the Incidence of Febrile Neutropenia Resulting in Hospital Admission Between the Branded Docetaxel and the Generic Formulations

Studies have raised concern about the safety of generic compared with branded drugs. Febrile neutropenia (FN) resulting in hospital admission was compared between the branded docetaxel (Taxotere®, Sanofi) and 2 generic formulations (docetaxel Ebewe and docetaxel Hospira) in patients with breast cancer. This was a retrospective study that included patients with breast cancer who received docetaxel between January 2012 and December 2014. Patients who had an admission diagnosis of FN and had received docetaxel within 14 days prior to admission were evaluated. The docetaxel brand and dose, patient characteristics, hospital length of stay, admission to the intensive care unit (ICU), and mortality were recorded. During the study period, 2904 cycles of docetaxel were given for 876 patients (1519 cycles of docetaxel Sanofi, 811 cycles of docetaxel Hospira, and 574 cycles of docetaxel Ebewe). Among the cycles given, 130 cycles were associated with FN that required hospital admission. The overall incidence of FN resulting in hospital admission was significantly higher in patients who had received docetaxel Hospira, compared with patients who had received docetaxel Sanofi (47[5.8%] cycles vs 53 [3.5%] cycles, P = .009), but there was no significant difference between docetaxel Ebewe and docetaxel Sanofi (30[5.2%] cycles vs 53 [3.5%] cycles, P = .069). All cases of FN resolved except for 1 patient who died in the ICU after receiving docetaxel Ebewe. There was a significant difference in the incidence of FN between docetaxel Sanofi and docetaxel Hospira, but all cases in both groups resolved completely.

Clinical and genetic risk factors for epirubicin-induced cardiac toxicity in early breast cancer patients

Anthracycline-induced cardiotoxicity (ACT) is a well-known serious adverse drug reaction leading to substantial morbidity. The purpose of this study was to assess ACT occurrence and clinical and genetic risk factors in early breast cancer patients. In 6 genes of interest (ABCC1, ABCC2, CYBA, NCF4, RAC2, SLC28A3), 10 single nucleotide polymorphisms (SNPs) involved in ACT were selected based on a literature search. Eight hundred and seventy-seven patients treated between 2000 and 2010 with 3-6 cycles of (neo) adjuvant 5-fluorouracil, epirubicin and cyclophosphamide (FEC) were genotyped for these SNPs using Sequenom MassARRAY. Main outcome measures were asymptomatic decrease of left ventricular ejection fraction (LVEF) > 10 % and cardiac failure grade 3-5 (CTCAE 4.0). To evaluate the impact of these 10 SNPs as well as clinical factors (age, relative dose intensity of epirubicin, left-sided radiotherapy, occurrence of febrile neutropenia, and planned and received cycles of epirubicin) on decrease of LVEF and cardiac failure, we performed uni- and multivariable logistic regression analysis. Additionally, exploratory analyses including 11 additional SNPs related to the metabolism of anthracyclines were performed. After a median follow-up of 3.62 years (range 0.40-9.60), a LVEF decline of > 10 % occurred in 153 patients (17.5 %) and cardiac failure in 16 patients (1.8 %). In multivariable analysis, six cycles of FEC compared to three cycles received and heterozygous carriers of the rs246221 T-allele in ABCC1 relative to homozygous carriers of the T-allele were significantly associated with LVEF decline of > 10 % (OR 1.3, 95 % CI 1.1-1.4, p < 0.001 and OR 1.6, 95 % CI 1.1-2.3, p = 0.02). Radiotherapy for left-sided breast cancer was associated with cardiac failure (OR 3.7, 95 % CI 1.2-11.5, p 0.026). The other 9 SNPs and clinical factors tested were not significantly associated. In our exploratory analysis, no other SNPs related to anthracycline metabolism were retained in the multivariate model for prediction of LVEF decline. ACT in breast cancer patients is related to number of received cycles of epirubicin and left-sided radiotherapy. Additional studies should be performed to independently confirm the potential association between rs246221 in ABCC1 and LVEF.

Impact of genetic variability and treatment-related factors on outcome in early breast cancer patients receiving (neo-) adjuvant chemotherapy with 5-fluorouracil, epirubicin and cyclophosphamide, and docetaxel

To assess the impact of patient-related factors, including genetic variability in genes involved in the metabolism of chemotherapeutic agents, on breast cancer-specific survival (BCSS) and recurrence-free interval (RFI). We selected early breast cancer patients treated between 2000 and 2010 with 4-6 cycles of (neo-)adjuvant 5-fluorouracil, epirubicin, and cyclophosphamide (FEC) or 3 cycles FEC followed by 3 cycles docetaxel. Tumor stage/subtype; febrile neutropenia and patient-related factors such as selected single nucleotide polymorphisms and baseline laboratory parameters were evaluated. Multivariable Cox regression was performed. Of 991 patients with a mean follow-up of 5.2 years, 152 (15.3 %) patients relapsed and 63 (6.4 %) patients died. Advanced stage and more aggressive subtype were associated with poorer BCSS and RFI in multivariable analysis (p < 0.0001). Associations with worse BCSS in multivariable analysis were: homozygous carriers of the rs1057910 variant C-allele in CYP2C9 (hazard ratio [HR] 30.4; 95 % confidence interval [CI] 6.1-151.5; p < 0.001) and higher white blood cell count (WBC) (HR 1.2; 95 % CI 1.0-1.3; p = 0.014). The GT genotype of the ABCB1 variant rs2032582 was associated with better BCSS (HR 0.5; 95 % CI 0.3-0.9, p = 0.021). Following associations with worse RFI were observed: higher WBC (HR 1.1; 95 % CI 1.0-1.2; p = 0.026), homozygous carriers of the rs1057910 variant C-allele in CYP2C9 (HR 10.9; 95 % CI 2.5-47.9; p = 0.002), CT genotype of the CYBA variant rs4673 (HR 1.8; 95 % CI 1.2-2.7; p = 0.006), and G-allele homozygosity for the UGT2B7 variant rs3924194 (HR 3.4; 95 % CI 1.2-9.7, p = 0.023). Patient-related factors including genetic variability and baseline white blood cell count, impacted on outcome in early breast cancer.