Risk of febrile neutropenia in patients receiving emerging chemotherapy regimens

Mitigating acute chemotherapy-associated adverse events in patients with cancer

Despite the enthusiasm surrounding novel targeted agents and immunotherapies, chemotherapy remains the mainstay treatment for most human malignancies, either alone or in combination. Yet, the burden of chemotherapy-associated adverse events (CAAEs) remains high and, importantly, is associated with considerable morbidity, mortality and costs that affect patients across multiple dimensions, including physical, emotional and social functioning. CAAEs can directly affect patient outcomes and indirectly increase the risk of cancer recurrence by compromising treatment intensity and continuity. Systematic efforts to identify and critically summarize the evidence on management approaches for CAAEs remain limited. Herein, we review the most common acute CAAEs having a major effect on survival, quality of life, function and/or continuation of optimal therapy. We focus on selected acute toxicities that occur during treatment, summarizing their underlying pathophysiology, multifactorial aetiologies, evidenced-based treatments, prevention strategies and management recommendations. We also summarize the available evidence on risk factors, validated risk assessment tools and other efforts to optimize symptom control in patients most likely to benefit in order to personalize the prevention and treatment of acute CAAEs. Finally, we discuss innovative symptom monitoring and supportive care interventions that are under development to further improve the outcomes of patients with cancer.

Impact of granulocyte colony-stimulating factor on FOLFIRINOX-induced neutropenia prevention: A population pharmacokinetic/pharmacodynamic approach

AIMS

Granulocyte colony-stimulating factor (G-CSF) is frequently prescribed to prevent chemotherapy-induced neutropenia, but the administration schedule remains empirical in case of bimonthly chemotherapy such as FOLFIRINOX regimen. This pharmacokinetic/pharmacodynamic (PK/PD) study was performed to determine the effect of different G-CSF regimens on the incidence and duration of neutropenia following FOLFIRINOX administration in order to propose an optimal G-CSF dosing schedule.

METHODS

A population PK/PD model was developed to describe individual neutrophil time course from absolute neutrophil counts (ANC) obtained in 40 advanced cancer patients receiving FOLFIRINOX regimen. The structural model considered ANC dynamics, neutropenic effect of cytotoxics and the stimulating effect of G-CSF on neutrophils. Final model estimates were used to simulate different G-CSF dosing schedules for 1000 virtual subjects. The incidence and duration of neutropenia were then calculated for different G-CSF dosing schedules.

RESULTS

The final model successfully described the myelosuppressive effect induced by the 3 cytotoxics for all patients. Simulations showed that pegfilgrastim administration reduced the risk of severe neutropenia by 22.9% for subjects with low ANC at the start of chemotherapy. Median duration in this group was also shortened by 3.1 days when compared to absence of G-CSF. Delayed G-CSF administration was responsible for higher incidence and longer duration of neutropenia compared to absence of administration.

CONCLUSION

The PK/PD model well described our population's ANC data. Simulations showed that pegylated-G-CSF administration 24 hours after the end of chemotherapy seems to be the optimal schedule to reduce FOLFIRINOX-induced neutropenia. We also underline the potential negative effect of G-CSF maladministration.

Population Pharmacokinetic, Pharmacogenetic, and Pharmacodynamic Analysis of Cyclophosphamide in Ethiopian Breast Cancer Patients

Cyclophosphamide (CPA) containing chemotherapy regimen is the standard of care for breast cancer treatment in sub-Saharan Africa. Wide inter-individual variations in pharmacokinetics (PK) of cyclophosphamide (CPA) influence the efficacy and toxicity of CPA containing chemotherapy. Data on the pharmacokinetics (PK) profile of CPA and its covariates among black African patients is lacking. We investigated population pharmacokinetic/pharmacogenetic/pharmacodynamic (PK-PG-PD) of CPA in Ethiopian breast cancer patients. During the first cycle of CPA-based chemotherapy, the population PK parameters for CPA were determined in 267 breast cancer patients. Absolute neutrophil count was recorded at baseline and day 20 post-CPA administration. A population PK and covariate model analysis was performed using non-linear mixed effects modeling. Semi-mechanistic and empiric drug response models were explored to describe the relationship between the area under concentration-time curve (AUC), and neutrophil toxicity. One compartment model better described CPA PK with population clearance and apparent volume of distribution (V_D) of 5.41 L/h and 46.5 L, respectively. Inter-patient variability in CPA clearance was 54.5%. Patients carrying CYP3A5*3 or *6 alleles had lower elimination rate constant and longer half-life compared to wild type carriers. CYP2C9 *2 or *3 carriers were associated with increased clearance of CPA. Patients who received 500 mg/m² based CPA regimen were associated with a 32.3% lower than average clearance and 37.1% lower than average V_D compared to patients who received 600 mg/m². A 0.1 m² unit increase in body surface area (BSA) was associated with a 5.6% increment in V_D. The mean V_D (33.5 L) in underweight group (BMI < 18.5 kg/m²) was significantly lower compared to those of overweight (48.1 L) or obese patients (51.9 L) (p < 0.001). AUC of CPA was positively correlated with neutropenic toxicity. In conclusion, we report large between-patient variability in clearance of CPA. CYP3A5 and CYP2C9 genotypes, BSA, BMI, and CPA dosage regimen influence PK of CPA. Plasma CPA exposure positively predicts chemotherapy-associated neutropenic toxicity.

Febrile neutropenia and its associated hospitalization in breast cancer patients on docetaxel-containing regimen: A retrospective cohort study on duration of prophylactic GCSF administration

PURPOSE

To compare febrile neutropenia (FN) incidence and hospitalization among breast cancer patients on docetaxel with no granulocyte colony-stimulating factors (GCSF) primary prophylaxis (PP), 4/5-day PP, or 7-day PP.

METHODS

We identified 3916 breast cancer patients using docetaxel-cyclophosphamide (TC), doxorubicin-cyclophosphamide then docetaxel (AC-T), fluorouracil-epirubicin-cyclophosphamide then docetaxel (FEC-T), docetaxel-carboplatin-trastuzumab (TJH), or docetaxel-doxorubicin-cyclophosphamide (TAC) from a hospital pharmacy dispensing database in Hong Kong between 2014 and 2016. Patients were offered GCSF within 5 days since administering docetaxel. Outcomes included FN incidence, time to first hospitalization, hospitalization rate, and duration.

RESULTS

In TC regimen, FN incidence (with odds ratio, OR) of patients with no PP, 4/5-day PP, and 7-day PP was 21.69%, 7.95% (OR 0.31, p < 0.001), and 5.33% (OR 0.20, p < 0.001), respectively. In TJH regimen, FN incidence of patients with no PP, 4/5-day PP, and 7-day PP was 38.26%, 8.33% (OR 0.15, p < 0.001), and 8.57% (OR 0.15, p < 0.001), respectively. FN incidence of patients on AC-T regimen with no PP and 4/5-day PP was 20.93% and 6.84%, respectively (OR 0.28, p = 0.005); with FEC-T regimen, the incidence was 9.91% and 4.77%, respectively (OR 0.46, p = 0.035). Only 3.27% FN cases were not hospitalized. Mean (±standard deviation, SD) time to first hospitalization was 8.21 ± 2.44 days. Mean (±SD) duration of hospitalization for patients with no PP, 4/5-day PP, and 7-day PP was 4.66 ± 2.60, 4.37 ± 2.85, and 5.12 ± 2.97 days, respectively.

CONCLUSION

GCSF prophylaxis in breast cancer patients on docetaxel could reduce FN incidence and hospitalization. 4/5-day PP demonstrated similar efficacy to 7-day PP with superior saving benefits on healthcare expenditure.

CYP2J2∗7 Genotype Predicts Risk of Chemotherapy-Induced Hematologic Toxicity and Reduced Relative Dose Intensity in Ethiopian Breast Cancer Patients

Chemotherapy-induced hematologic toxicity is the primary reasons of dose reductions and/or delays, low relative dose intensity (RDI), and predicts anticancer response. We investigated the incidence and predictors of chemotherapy-induced hematologic toxicities and reduced RDI in Ethiopian breast cancer patients, and implication of pharmacogenetics variations. Breast cancer patients (n = 249) were enrolled prospectively to receive cyclophosphamide based chemotherapy. Hematological toxicity (neutropenia, anemia, and thrombocytopenia) were monitored throughout chemotherapy cycle. The primary and secondary outcomes were incidence of grade 3 or 4 toxicity and reduced RDI, respectively. CYP2B6^∗6, CYP3A5^∗3, CYP2C9 (^∗2,^∗3), CYP2C19 (^∗2,^∗3), CYP2J2^∗7, POR^∗28, and ABCB1 (rs3842) genotyping were done. Cox proportional hazard and logistic regression were used to estimate risk predictors of toxicity and reduced RDI, respectively. Majority (73.5%) of the patients were < 45 years of age. The incidence of grade 3 or 4 hematological toxicity was 51.0% (95% CI = 44.54–57.46%). Multivariate Cox proportional hazard regression indicated CYP2J2^∗7 genotype [Hazard ratio (HR) = 1.82; 95% CI = 1.14–2.90], pretreatment grade 1 leukopenia (HR = 2.75; 95% CI = 1.47–5.15) or grade 1 or 2 neutropenia (HR = 2.75; 95% CI = 1.73–4.35) as significant predictors of hematologic toxicities. The odds of having hematologic toxicities was lower in CYP2C9^∗2 or ^∗3 carriers (p = 0.024). The prevalence of reduced RDI was 56.6% (95% CI = 50.3–62.9%). Higher risk of reduced RDI was associated with CYP2J2^∗7 allele [Adjusted odds ratio (AOR) = 2.79; 95% CI = 1.21–6.46], BMI ≤ 18.4 kg/m² (AOR = 5.98; 95% CI = 1.36–26.23), baseline grade 1 leukopenia (AOR = 6.09; 95% CI = 1.24–29.98), and baseline neutropenia (AOR = 3.37; 95% CI = 1.41–8.05). The odds of receiving reduced RDI was lower in patients with CYP2B6 ^∗6/^∗6 genotype (AOR = 0.19; 95% CI = 0.06–0.77). We report high incidence of chemotherapy-induced hematological toxicities causing larger proportion of patients to receive reduced RDI in Ethiopian breast cancer patients. Patients carrying CYP2J2^∗7 allele and low baseline blood counts are at a higher risk for chemotherapy-induced hematologic toxicities and receiving reduced RDI, and may require prior support and close follow up during chemotherapy.

Retrospective comparison of the efficacy and the toxicity of standard and modified FOLFIRINOX regimens in patients with metastatic pancreatic adenocarcinoma

BACKGROUND

FOLFIRINOX stands a major breakthrough in the management of metastatic pancreatic adenocarcinoma (MPA). Nonetheless, significant side-effects have been reported using standard FOLFIRINOX. We aimed to compare survival outcomes, response rates and toxicity of patients treated with standard or modified FOLFIRINOX in MPA.

METHODS

We included patients aged ≥18 years old, with pathologically confirmed MPA, treated with FOLFIRINOX in the first-line setting. Patients submitted to at least one cycle of full-dose FOLFIRINOX were grouped in the standard FOLFIRINOX group.

RESULTS

Patients treated with standard FOLFIRINOX were younger and had less comorbidity. We observed no differences in overall survival or in progression-free survival between the two treatment arms. The only variable independently associated with OS was log10[neutrophil-to-lymphocyte ratio (NLR)]. Modified FOLFIRINOX was associated with a lower dose reduction rate, but a slightly increased incidence of severe toxicity.

CONCLUSIONS

Modified FOLFIRINOX presents the same activity against MPA as standard FOLFIRINOX. We found no significant differences in toxicity, possibly due to patient selection and a higher dose reduction rate in the standard FOLFIRINOX arm. NLR stood as an important prognostic marker and further research is needed to comprehend its biological meaning in pancreatic cancer.

Dose modifications in adjuvant chemotherapy for solid organ malignancies: A systematic review of clinical trials

Toxicities of systemic cancer therapies are often less frequently observed in clinical trials than in clinical practice, due to the careful selection of patients with fewer comorbidities. Although guidelines exist for the estimation of chemotherapy dose, clinical factors like age, comorbid illness and extremes of body habitus are not considered in the method of dose calculation, which can result in significant toxicity. We reviewed the referenced clinical trials from which the evidence-based curative-intent cancer treatment protocols were developed for EVIQ, which is an Australian government, online resource. This review shows that a significant proportion of patients in curative-intent clinical trials experience toxicities that result in dose modifications-dose reduction, dose delays or missed doses-despite strict selection criteria and intense monitoring. Thus, even in ideal, clinical-trial settings chemotherapy dose calculation remains imprecise and subject to adjustment as clinically appropriate. In real-world clinical practice, dose alterations or modifications in response to toxicities need to be thoroughly discussed and implemented with clear understanding of the patient with appropriate documentation. This review may be used as a reference in these situations to elaborate the extent of toxicities seen in clinical trials with optimal settings.

Toxicity of docetaxel, carboplatin, and trastuzumab combination as adjuvant or neo-adjuvant treatment for Her2 positive breast cancer patients and impact of colony-stimulating factor prophylaxis

While the docetaxel, carboplatin, and trastuzumab (TCH) regimen is one of the standard treatments in Her2-positive breast cancer, however, acute toxicities, especially those related to the high rate of neutropenia are consistently reported. Primary: To compare the toxicity of TCH in current clinical practice vs the toxicity observed in the pivotal study, comparing the toxicity in patients that received primary prophylaxis (PP) with colony-stimulating factors vs those that did not receive PP. Secondary: To describe the demographic and clinical characteristics of the study sample, as well as the adverse effects and survival. The data regarding 95 patients were analyzed. Observed toxicity (hematological and extra-hematological) was greater compared to the pivotal study, with the exception of neuropathy and neutropenia. Toxicities "PP" vs "no PP": Extra-hematological grade 3-4 toxicities: Significant reduction was observed in the "PP" group vs the "no PP" group referred to fatigue, stomatitis, nausea, and vomiting. Hematological grade 3-4 toxicities: Lesser neutropenia, leukopenia, and febrile neutropenia were observed in the "PP" group. Complications associated to treatment: No grade 3-4 cardiac toxicity, leukemia or deaths were recorded. DFS and OS: After a mean follow-up of 22.9 months, only one bone metastatic relapse was detected (DFS: 98.9%; OS: 100%). The combination TCH is very active and effective as adjuvant and neo-adjuvant therapy in Her2-positive breast cancer, and is currently regarded as standard treatment. However, global toxicity as well as hematological toxicity is elevated. The incorporation of PP to TCH significantly reduces hematological toxicity and some of the global toxicity, thus favoring treatment implementation and lessening the clinical complications. We therefore recommend generalization of PP with colony-stimulating factors in patients receiving TCH.

Time trends in utilization of G-CSF prophylaxis and risk of febrile neutropenia in a Medicare population receiving adjuvant chemotherapy for early-stage breast cancer

PURPOSE

The purpose of this study is to assess temporal trends in the use of granulocyte colony-stimulating factor (G-CSF) prophylaxis and risk of febrile neutropenia (FN) among older women receiving adjuvant chemotherapy for early-stage breast cancer.

METHODS

Women aged ≥ 66 years with diagnosis of early-stage breast cancer who initiated selected adjuvant chemotherapy regimens were identified using the SEER-Medicare data from 2002 to 2012. Adjusted, calendar-year-specific proportions were estimated for use of G-CSF primary prophylaxis (PP) and secondary prophylaxis and FN risk in the first and the second/subsequent cycles during the first course of chemotherapy, using logistic regression models. calendar-year-specific mean probabilities were estimated with covariates set to modal values.

RESULTS

Among 11,107 eligible patients (mean age 71.7 years), 74% received G-CSF in the first course of chemotherapy. Of all patients, 5819 (52%) received G-CSF PP, and among those not receiving G-CSF PP, only 5% received G-CSF secondary prophylaxis. The adjusted proportion using G-CSF PP increased from 6% in 2002 to 71% in 2012. During the same period, the adjusted risk of FN in the first cycle increased from 2% to 3%; the adjusted risk increased from 1.5% to 2.9% among those receiving G-CSF PP and from 2.3% to 3.5% among those not receiving G-CSF PP.

CONCLUSION

The use of G-CSF PP increased substantially during the study period. Although channeling of higher-risk patients to treatment with G-CSF PP is expected, the adjusted risk of FN among patients treated with G-CSF PP tended to be lower than among those not receiving G-CSF PP.

Issues on the Use of White Blood Cell Growth Factors in Oncology Practice

Appropriate use of myeloid growth factors may reduce the risk of neutropenic complications including febrile neutropenia (FN) in patients receiving cancer chemotherapy. The recently updated American Society of Clinical Oncology (ASCO) Guidelines on the Use of the White Blood Cell Growth Factors recommends routine prophylaxis with these agents starting in the first cycle when the risk of FN is 20% or greater. However, the risks for neutropenic complications and the risk of serious adverse consequences from FN vary considerably with different chemotherapy regimens as well as other disease-, treatment-, and patient-specific risk factors. Considerably more information is now available on the major risk factors for FN. Multivariable risk models combining factors look promising but require further validation. Most clinical studies of myeloid growth factor prophylaxis assessed relative risk (RR) of FN but were not powered to evaluate the effect of prophylaxis on disease-free or overall survival. Accumulating evidence suggests, however, that the appropriate use of these agents in selected patients may improve both short-term and long-term survival by reducing the immediate risk of mortality accompanying patients with high-risk disease developing FN as well as improving disease-free and overall survival by enabling the delivery of full dose intensity chemotherapy and reducing the risk of disease recurrence in patients treated with curative intent. Further studies to evaluate risk factors and models for FN are needed to guide clinical and shared decision making for the optimal personalized use of these agents and offer patients at increased risk the best chance of long-term disease control.

Risk of Neutropenia-Related Hospitalization in Patients Who Received Colony-Stimulating Factors With Chemotherapy for Breast Cancer

Purpose

To describe outcomes after granulocyte colony-stimulating factor (G-CSF) prophylaxis in patients with breast cancer who received chemotherapy regimens with low-to-intermediate risk of induction of neutropenia-related hospitalization.

Patients and Methods

We identified 8,745 patients age ≥ 18 years from a medical and pharmacy claims database for 14 commercial US health plans. This retrospective analysis included patients with breast cancer who began first-cycle chemotherapy from 2008 to 2013 using docetaxel and cyclophosphamide (TC); docetaxel, carboplatin, and trastuzumab (TCH); or doxorubicin and cyclophosphamide (conventional-dose AC) regimens. Primary prophylaxis (PP) was defined as G-CSF administration within 5 days of beginning chemotherapy. Outcome was neutropenia, fever, or infection-related hospitalization within 21 days of initiating chemotherapy. Multivariable regressions and number-needed-to-treat analyses were used.

Results

A total of 4,815 patients received TC (2,849 PP; 1,966 no PP); 2,292 patients received TCH (1,444 PP; 848 no PP); and 1,638 patients received AC (857 PP; 781 no PP) regimen. PP was associated with reduced risk of neutropenia-related hospitalization for TC (2.0% PP; 7.1% no PP; adjusted odds ratio [AOR], 0.29; 95% CI, 0.22 to 0.39) and TCH (1.3% PP; 7.1% no PP; AOR, 0.19; 95% CI, 0.12 to 0.30), but not AC (4.7% PP; 3.8% no PP; AOR, 1.21; 95% CI, 0.75 to 1.93) regimens. For the TC regimen, 20 patients (95% CI, 16 to 26) would have to be treated for 21 days to avoid one neutropenia-related hospitalization; with the TCH regimen, 18 patients (95% CI, 13 to 25) would have to be treated.

Conclusion

Primary G-CSF prophylaxis was associated with low-to-modest benefit in lowering neutropenia-related hospitalization in patients with breast cancer who received TC and TCH regimens. Further evaluation is needed to better understand which patients benefit most from G-CSF prophylaxis in this setting.

The impact of chemotherapy dose intensity and supportive care on the risk of febrile neutropenia in patients with early stage breast cancer: a prospective cohort study

Background

Febrile neutropenia (FN) is a major dose-limiting toxicity of cancer chemotherapy resulting in considerable morbidity, mortality, and cost. This study evaluated the time course of neutropenic events and patterns of supportive care interventions in patients receiving chemotherapy for early-stage breast cancer treated in oncology community practices.

Methods

A prospective cohort study of adult cancer patients initiating a new chemotherapy regimen was conducted at 115 US sites. Toxicity associated with chemotherapy including neutropenic and infectious complications was recorded over four cycles. Clinical interventions were recorded including reductions in chemotherapy dose intensity and use of supportive care measures.

Results

A total of 1,202 patients with stage I–III breast cancer were evaluated. The majority of neutropenic (116 of 196) and infection events (179 of 325) occurred in the initial cycle. A decrease in occurrence of FN and infection was observed in the subsequent cycles, along with an increase in utilization of colony stimulating factors (CSFs), antibiotics and reductions in chemotherapy dose intensity. The overall risk of FN in all patients was 16.3%. In patients who started treatment at or near full dose intensity, the FN risk reached 21.0% without primary CSF prophylaxis and it was 9.0% with prophylaxis. There was no significant difference in FN rates by menopausal or hormone receptors status.

Conclusions

The risk of neutropenic complications is greatest in the initial cycle when most patients receive full-dose chemotherapy. A decrease in neutropenic events during subsequent cycles is associated with reduced dose intensity or increased use of supportive care measures. However, the cumulative risk of FN remains high in patients with early-stage breast cancer receiving full dose chemotherapy without prophylactic measures.

Management of breast cancer patients with chemotherapy-induced neutropenia or febrile neutropenia

Chemotherapy-induced neutropenia (CIN) is a common toxicity caused by the administration of anticancer drugs. This side effect is associated with life-threatening infections and may alter the chemotherapy schedule, thus impacting on early and long-term outcomes. Elderly breast cancer patients with impaired health status or advanced disease as well as patients undergoing dose-dense anthracycline/taxane- or docetaxel-based regimens have the highest risk of CIN. A careful assessment of the baseline risk for CIN allows the selection of patients who need primary prophylaxis with granulocyte colony-stimulating factor (G-CSF) and/or antimicrobial agents. Neutropenic cancer patients may develop febrile neutropenia and CIN-related severe medical complications. Specific risk assessment scores, along with comprehensive clinical evaluation, are able to define a group of febrile patients with low risk for complications who can be safely treated as outpatients. Conversely, patients with higher risk of severe complications should be hospitalized and should receive intravenous antibiotic therapy with or without G-CSF.