Dose-response effect of adjuvant cyclophosphamide, methotrexate, 5-fluorouracil (CMF) in node-positive breast cancer. International Breast Cancer Study Group

Impaired microvascular reactivity in patients treated with 5-fluorouracil chemotherapy regimens: Potential role of endothelial dysfunction

Background

5-fluorouracil (5-FU) is the second most common cancer chemotherapy associated with short- and long-term cardiotoxicity. Although the mechanisms mediating these toxicities are not well understood, patients often present with symptoms suggestive of microvascular dysfunction. We tested the hypotheses that patients undergoing cancer treatment with 5-FU based chemotherapy regimens would present with impaired microvascular reactivity and that these findings would be substantiated by decrements in endothelial nitric oxide synthase (eNOS) gene expression in 5-FU treated human coronary artery endothelial cells (HCAEC).

Methods

We first performed a cross-sectional analysis of 30 patients undergoing 5-FU based chemotherapy treatment for cancer (5-FU) and 32 controls (CON) matched for age, sex, body mass index, and prior health history (excluding cancer). Cutaneous microvascular reactivity was evaluated by laser Doppler flowmetry in response to endothelium-dependent (local skin heating; acetylcholine iontophoresis, ACh) and -independent (sodium nitroprusside iontophoresis, SNP) stimuli. In vitro experiments in HCAEC were completed to assess the effects of 5-FU on eNOS gene expression.

Results

5-FU presented with diminished microvascular reactivity following eNOS-dependent local heating compared to CON (P = 0.001). Iontophoresis of the eNOS inhibitor L-NAME failed to alter the heating response in 5-FU (P = 0.95), despite significant reductions in CON (P = 0.03). These findings were corroborated by lower eNOS gene expression in 5-FU treated HCAEC (P < 0.01) compared to control. Peak vasodilation to ACh (P = 0.58) nor SNP (P = 0.39) were different between groups.

Conclusions

The present findings suggest diminished microvascular function along the eNOS-NO vasodilatory pathway in patients with cancer undergoing treatment with 5-FU-based chemotherapy regimens and thus, may provide insight into the underlying mechanisms of 5-FU cardiotoxicity.

'ADVANCE' (a pilot trial) ADjuVANt chemotherapy in the elderly: Developing and evaluating lower-toxicity chemotherapy options for older patients with breast cancer

INTRODUCTION

Older adults with breast cancer receiving neo/adjuvant chemotherapy are at high risk for poor outcomes and are underrepresented in clinical trials. The ADVANCE (ADjuVANt Chemotherapy in the Elderly) trial evaluated the feasibility of two neo/adjuvant chemotherapy regimens in parallel-enrolling cohorts of older patients with human epidermal growth factor receptor 2-negative breast cancer: cohort 1-triple-negative; cohort 2-hormone receptor-positive.

MATERIALS AND METHODS

Adults age ≥ 70 years with stage I-III breast cancer warranting neo/adjuvant chemotherapy were enrolled. Cohort 1 received weekly carboplatin (area under the curve 2) and weekly paclitaxel 80 mg/m2 for twelve weeks; cohort 2 received weekly paclitaxel 80 mg/m2 plus every-three-weekly cyclophosphamide 600 mg/m2 over twelve weeks. The primary study endpoint was feasibility, defined as ≥80% of patients receiving ≥80% of intended weeks/doses of therapy. All dose modifications were applied per clinician discretion.

RESULTS

Forty women (n = 20 per cohort) were enrolled from March 25, 2019 through August 3, 2020 from three centers; 45% and 35% of patients in cohorts 1 and 2 were age > 75, respectively. Neither cohort achieved targeted thresholds for feasibility. In cohort 1, eight (40.0%) met feasibility (95% confidence interval [CI] = 19.1-63.9%), while ten (50.0%) met feasibility in cohort 2 (95% CI = 27.2-72.8). Neutropenia was the most common grade 3-4 toxicity (cohort 1-65%, cohort 2-55%). In cohort 1, 80% and 85% required ≥1 dose holds of carboplatin and/or paclitaxel, respectively. In cohort 2, 10% required dose hold(s) for cyclophosphamide and/or 65% for paclitaxel.

DISCUSSION

In this pragmatic pilot examining chemotherapy regimens in older adults with breast cancer, neither regimen met target goals for feasibility. Developing efficacious and tolerable regimens for older patients with breast cancer who need chemotherapy remains an important goal.

CLINICALTRIALS

gov Identifier: NCT03858322.

Clinical Impact of Primary Prophylactic Pegfilgrastim in Breast Cancer Patients Receiving Adjuvant Docetaxel-Doxorubicin-Cyclophosphamide Chemotherapy

Purpose

The regimen including concurrent docetaxel, doxorubicin, and cyclophosphamide (TAC) has been categorized as an important risk factor for febrile neutropenia (FN). This comparative study examined the clinical impact of long-acting granulocyte colony-stimulating factor (G-CSF) (pegfilgrastim) during adjuvant TAC chemotherapy in Korean patients with advanced breast cancer.

Methods

We analyzed data from 239 patients who received 6 cycles of adjuvant TAC chemotherapy. We categorized patients into 2 groups according to the use of primary prophylactic pegfilgrastim and compared the incidence and risk of FN, hospital care costs, and survival in the 2 groups.

Results

The incidence of FN decreased from 54.2% to 21.2% in all patients, after the use of pegfilgrastim. The analysis of a total of 1,432 chemotherapy cycles showed that the incidence of FN decreased from 36.1% to 9.1% after the use of pegfilgrastim. Moreover, the decrease in the incidence of FN with the use of pegfilgrastim resulted in a significant decrease in the mean duration of neutropenia (4.15 to 1.29 days), the risk of hospitalization (99.5% to 29.7%) and the mean total hospital care cost (USD 3,038 to USD 2,347). High relative dose intensity (RDI) in patients treated with pegfilgrastim than in those not treated with pegfilgrastim (99.18% vs. 93.85%) was associated with a better overall survival (p = 0.033).

Conclusions

The use of pegfilgrastim during adjuvant TAC chemotherapy was significantly associated with a decrease in the incidence and risk of FN, hospital care costs, and risk of death compared to the use of adjuvant TAC without primary prophylaxis.

Impact of Cumulative Chemotherapy Dose on Survival With Adjuvant FEC-D Chemotherapy for Breast Cancer

BACKGROUND

Reductions in adjuvant chemotherapy dose <85% for historical regimens (ie, cyclophosphamide/methotrexate/fluorouracil) are known to affect breast cancer survival. This threshold, in addition to early versus late dose reductions, are poorly defined for third-generation anthracycline/taxane-based chemotherapy. In patients with breast cancer receiving adjuvant 5-fluorouracil/epirubicin/cyclophosphamide followed by docetaxel (FEC-D), we evaluated the impact of chemotherapy total cumulative dose (TCD), and early (FEC) versus late (D only) dose reductions, on survival outcomes.

PATIENTS AND METHODS

Women with stage I-III, hormone receptor-positive/negative, HER2-negative breast cancer treated with adjuvant FEC-D chemotherapy from 2007 through 2014 in Alberta, Canada, were included. TCD for cycles 1 to 6 of <85% or ≥85% was calculated. Average cumulative dose was also calculated for early (cycles 1-3) and late (cycles 4-6) chemotherapy. Survival outcomes (disease-free survival [DFS] and overall survival [OS]) were estimated using Kaplan-Meier and multivariate analysis. Cohorts were evaluated for uniformity.

RESULTS

Characteristics were reasonably balanced for all cohorts. Overall, 1,302 patients were evaluated for dose reductions, with 16% being reduced <85% (n=202) relative to ≥85% (n=1,100; 84%). Patients who received TCD ≥85% relative to <85% had superior 5-year DFS (P=.025) and OS (P<.001) according to Kaplan-Meier analysis, which remained significant on univariate and multivariate analyses. In stratified late and early dose reduction cohorts, DFS and OS showed a significant inferior survival trend for dose reduction early in treatment administration in 5-year Kaplan-Meier (P=.002 and P<.001, respectively) and multivariate analyses (hazard ratio [HR], 1.46; P=.073, and HR, 1.77; P=.011, respectively). Dose delays of <14 or ≥14 days and granulocyte colony-stimulating factor use did not affect outcomes.

CONCLUSIONS

Chemotherapy TCD <85% for adjuvant FEC-D affects breast cancer survival. Late reductions (D only) were not shown to adversely affect DFS or OS. Conversely, early reductions (FEC±D) negatively affected patient outcomes.

Dose tailoring of adjuvant chemotherapy for breast cancer based on hematologic toxicities: further results from the prospective PANTHER study with focus on obese patients

Background

Adjuvant chemotherapy (ACT) for breast cancer improves relapse-free survival (BCRFS) and overall survival. Differences in terms of efficacy and toxicity could partly be explained by the significant interpatient variability in pharmacokinetics which cannot be captured by dosing according to body surface area. Consequently, tailored dosing was prospectively evaluated in the PANTHER trial.

Patients and methods

PANTHER is a multicenter, open-label, randomized phase III trial which compared tailored, dose-dense (DD) epirubicin/cyclophosphamide (E/C) and tailored docetaxel (D) (tDD) with standard interval 5-fluorouracil/E/C and D. The primary end point was BCRFS and the primary efficacy analysis has been previously published. In this secondary analysis, we aimed to retrospectively explore the concept of dose tailoring. Our two hypotheses were that BCRFS would not vary depending on the cumulative administered epirubicin dose; and that dose tailoring would lead to appropriate dosing and improved outcomes for obese patients, who are known to have worse prognosis and increased toxicity after DD ACT.

Results

Patients treated with tDD had similar BCRFS regardless of the cumulative epirubicin dose (P = 0.495), while obese patients in this group [body mass index (BMI) ≥30] had improved BCRFS compared with nonobese ones (BMI <30) [hazard ratio (HR) = 0.51, 95% confidence interval (CI) 0.30-0.89, P = 0.02]. Moreover, tDD was associated with improved BCRFS compared with standard treatment only in obese patients (HR = 0.49, 95% CI 0.26-0.90, P = 0.022) but not in nonobese ones (HR = 0.79, 95% CI 0.60-1.04, P = 0.089). The differences were not formally statistically significant (P for interaction 0.175). There were no differences in terms of toxicity across the epirubicin dose levels or the BMI groups.

Conclusions

Dose tailoring is a feasible strategy that can potentially improve outcomes in obese patients without increasing toxicity and should be pursued in further clinical studies.

ClinicalTrials.gov identifier

NCT00798070.

GTSE1 is involved in breast cancer progression in p53 mutation-dependent manner

Background

With the rapid development of the high throughput detection techniques, tumor-related Omics data has become an important source for studying the mechanism of tumor progression including breast cancer, one of the major malignancies worldwide. A previous study has shown that the G2 and S phase-expressed-1 (GTSE1) can act as an oncogene in several human cancers. However, its functional roles in breast cancer remain elusive.

Method

In this study, we analyzed breast cancer data downloaded from The Cancer Genome Atlas (TCGA) databases and other online database including the Oncomine, bc-GenExMiner and PROGgeneV2 database to identify the molecules contributing to the progression of breast cancer. The GTSE1 expression levels were investigated using qRT-PCR, immunoblotting and IHC. The biological function of GTSE1 in the growth, migration and invasion of breast cancer was examined in MDA-MB-231, MDA-MB-468 and MCF7 cell lines. The in vitro cell proliferative, migratory and invasive abilities were evaluated by MTS, colony formation and transwell assay, respectively. The role of GTSE1 in the growth and metastasis of breast cancer were revealed by in vivo investigation using BALB/c nude mice.

Results

We showed that the expression level of GTSE1 was upregulated in breast cancer specimens and cell lines, especially in triple negative breast cancer (TNBC) and p53 mutated breast cancer cell lines. Importantly, high GTSE1 expression was positively correlated with histological grade and poor survival. We demonstrated that GTSE1 could promote breast cancer cell growth by activating the AKT pathway and enhance metastasis by regulating the Epithelial-Mesenchymal transition (EMT) pathway. Furthermore, it could cause multidrug resistance in breast cancer cells. Interestingly, we found that GTSE1 could regulate the p53 function to alter the cell cycle distribution dependent on the mutation state of p53.

Conclusion

Our results reveal that GTSE1 played a key role in the progression of breast cancer, indicating that GTSE1 could serve as a novel biomarker to aid in the assessment of the prognosis of breast cancer.

Electronic supplementary material

The online version of this article (10.1186/s13046-019-1157-4) contains supplementary material, which is available to authorized users.

Does adjuvant chemotherapy dose modification have an impact on the outcome of patients diagnosed with advanced stage ovarian cancer? An NRG Oncology/Gynecologic Oncology Group study

PURPOSE

To determine the relationship between chemotherapy dose modification (dose adjustment or treatment delay), overall survival (OS) and progression-free survival (PFS) for women with advanced-stage epithelial ovarian carcinoma (EOC) and primary peritoneal carcinoma (PPC) who receive carboplatin and paclitaxel.

METHODS

Women with stages III and IV EOC and PPC treated on the Gynecologic Oncology Group phase III trial, protocol 182, who completed eight cycles of carboplatin with paclitaxel were evaluated in this study. The patients were grouped per dose modification and use of granulocyte colony stimulating factor (G-CSF). The primary end point was OS; Hazard ratios (HR) for PFS and OS were calculated for patients who completed eight cycles of chemotherapy. Patients without dose modification were the referent group. All statistical analyses were performed using the R programming language and environment.

RESULTS

A total of 738 patients were included in this study; 229 (31%) required dose modification, 509 did not. The two groups were well-balanced for demographic and prognostic factors. The adjusted hazard ratios (HR) for disease progression and death among dose-modified patients were: 1.43 (95% CI, 1.19-1.72, P < 0.001) and 1.26 (95% CI, 1.04-1.54, P = 0.021), respectively. Use of G-CSF was more frequent in dose-modified patients with an odds ratio (OR) of 3.63 (95% CI: 2.51-5.26, P < 0.001) compared to dose-unmodified patients.

CONCLUSION

Dose-modified patients were at a higher risk of disease progression and death. The need for chemotherapy dose modification may identify patients at greater risk for adverse outcomes in advanced stage EOC and PPC.

Long-term safety and survival outcomes from the Scandinavian Breast Group 2004-1 randomized phase II trial of tailored dose-dense adjuvant chemotherapy for early breast cancer

PURPOSE

Although adjuvant polychemotherapy improves outcomes for early breast cancer, the significant variability in terms of pharmacokinetics results in differences in efficacy and both short and long-term toxicities. Retrospective studies support the use of dose tailoring according to the hematologic nadirs.

METHODS

The SBG 2004-1 trial was a randomized feasibility phase II study which assessed tailored dose-dense epirubicin and cyclophosphamide (EC) followed by docetaxel (T) (group A), the same regimen with fixed doses (group B) and the TAC regimen (group C). Women aged 18-65 years, ECOG PS 0-1 with at least one positive axillary lymph node were randomized 1:1:1. The primary endpoint of the study was the safety and feasibility of the treatment. Toxicity was graded according to CTC-AE version 3.0. The design and short-term toxicity have been previously published. Here, we report safety and efficacy data after 10 years of follow-up.

RESULTS

A total of 124 patients were included in the study. After a median follow-up of 10.3 years, the probability for 10-year survival was 78.5, 75.1, and 63.4% and for relapse free survival 64.1, 71.0, and 59.5% for groups A, B, and C, respectively. There were no cases of clinically diagnosed cardiotoxicity or hematologic malignancies. No patient was lost to follow-up.

CONCLUSIONS

In this randomized phase II trial, tailored dose adjuvant chemotherapy was feasible, without an increased risk for long-term adverse events after a median follow-up of 10 years.

Dose intense, dose dense and tailored dose adjuvant chemotherapy for early breast cancer: an evolution of concepts

BACKGROUND

The introduction of adjuvant chemotherapy following surgery for early breast cancer (BC) and its integration into routine clinical practice has consistently improved clinical outcomes. Since the addition of other agents to the contemporary standard of care containing an anthracycline, cyclophosphamide and a taxane has not lead to further prolongation of survival, subsequent efforts concentrated on escalating the administered doses and reducing the time interval between chemotherapy cycles. These strategies have been extensively evaluated in randomized trials and dose dense chemotherapy is now recommended by clinical practice guidelines.

METHOD

Eligible trials were identified by searching the EMBASE, Pubmed, Scopus and Cochrane Library databases, as well as conference papers. The findings, shortcomings and impact of these studies are presented and critically discussed.

RESULTS

Although a large number of randomized trials has established the value of adjuvant chemotherapy, important questions remain unanswered. Ongoing research focuses on omitting treatment in good risk patients, identifying patients most likely to benefit from a dose dense approach and on administering personalized doses such as in tailored dose chemotherapy.

CONCLUSIONS

Adjuvant chemotherapy for early BC is an evolving art. Further optimizations could potentially improve outcomes for a patient subset and spare others from unnecessary treatment-related toxicity.

Prognostic nutritional index before adjuvant chemotherapy predicts chemotherapy compliance and survival among patients with non-small-cell lung cancer

Background

Adjuvant chemotherapy after the complete resection of non-small-cell lung cancer (NSCLC) is now the standard of care. To improve survival, it is important to identify risk factors for the continuation of adjuvant chemotherapy. In this study, we analyzed chemotherapy compliance and magnitude of the prognostic impact of the prognostic nutritional index (PNI) before adjuvant chemotherapy.

Methods

We conducted a retrospective review of data from 106 patients who had received adjuvant chemotherapy. The adjuvant chemotherapy consisted of an oral tegafur agent (OT) or platinum-based chemotherapy (PB). The correlations between the PNI values and recurrence-free survival (RFS) were then evaluated.

Results

In the PB group, the percentage of patients who completed the four planned cycles of chemotherapy was not correlated with the PNI. In the OT group, however, a significant difference was observed in the percentage of patients who completed the planned chemotherapy according to the PNI before adjuvant chemotherapy. The RFS of patients with a PNI <50 before adjuvant chemotherapy was significantly poorer than that of the patients with a PNI ≥50. A multivariate analysis showed that nodal metastasis and PNI before chemotherapy were independent predictors of the RFS. However, PNI before surgery was not a predictor of the RFS. In the subgroup analysis, PNI before chemotherapy was independent predictor of the RFS in the OT group (P=0.019), but not in the PB group (P=0.095).

Conclusion

The PNI before adjuvant chemotherapy influenced the treatment compliance with the planned chemotherapy in the OT group, but not the PB group. In addition, a low PNI before adjuvant chemotherapy was associated with a poor RFS in a multivariate analysis, especially in the OT group.

A randomised trial of secondary prophylaxis using granulocyte colony-stimulating factor ('SPROG' trial) for maintaining dose intensity of standard adjuvant chemotherapy for breast cancer by the Anglo-Celtic Cooperative Group and NCRN

BACKGROUND

Guidelines on the use of haematopoietic colony-stimulating factors for patients having adjuvant chemotherapy for breast cancer are designed to minimise the risk of neutropaenic infection (Smith TJ, Khatcheressian J, Lyman GH et al. Update of recommendations for the use of white blood cell growth factors: an evidence-based clinical practice guideline. J Clin Oncol 2006; 3: 187-205; Aapro MS, Bohlius J, Cameron DA et al. Effect of primary prophylactic G-CSF use on systemic therapy administration for elderly breast cancer patients. Breast Cancer Res Treat 2011; 47: 8-32; Carlson RW, Allred DC, Anderson BO et al. Breast cancer. Clinical practice guidelines in oncology. J Natl Compr Canc Netw 2009; 7: 122-192). Non-randomised data suggest that the achievement of planned dose intensity (DI) may have an important effect on survival. This trial compared the effects of granulocyte colony-stimulating factor, GCSF, against standard management following a first neutropaenic event (NE) in achieving planned DI.

PATIENTS AND METHODS

Adult patients receiving adjuvant or neoadjuvant chemotherapy were randomised following a first NE, defined as hospitalisation due to neutropaenic fever, an absolute neutrophil count (ANC) ≤1.5 × 10(9)/l requiring treatment delay or dose reduction of 15% or more of planned dose. The study was initially planned to enrol 816 patients to detect a difference of 10%. This was difficult to achieve in the timeframe and the trial size was amended. Thus, 407 patients were randomly assigned to filgrastim for 7 days or pegfilgrastim versus standard care. The amended study was designed to have 80% power to detect an absolute difference of 14% of planned DI between the two groups.

RESULTS

Most regimens were anthracycline-based many of which included a sequential taxane and/or were in clinical trials. Around 82.7% had an NE in the first three cycles. A total of 401 had calculable relative dose intensity (RDI) data. A target of 85% planned RDI was achieved in only 50% of patients in the control arm compared with 75% in the GCSF arm (P < 0.0001). A secondary end point revealed a reduction in post-randomisation NEs, 65.7% controls versus 18.2% with GCSF.

CONCLUSIONS

Secondary intervention with GCSF showed a statistically significant improvement in the achievement of adequate RDI in non-intensive regimens. This may have important clinical implications for outcome.

Leucopenia and treatment efficacy in advanced nasopharyngeal carcinoma

BACKGROUND

Leucopenia or neutropenia during chemotherapy predicts better survival in several cancers. We aimed to assess whether leucopenia could be a biological measure of treatment and a marker of efficacy in advanced nasopharyngeal carcinoma (ANPC).

METHODS

We retrospectively analyzed 3826 patients with ANPC who received chemoradiotherapy. Leucopenia was categorised on the basis of worst grade during treatment according to the National Cancer Institute Common Toxicity Criteria version 4.0: no leucopenia (grade 0), mild leucopenia (grade 1-2), and severe leucopenia (grade 3-4). Associations between leucopenia and survival were estimated by Cox proportional hazards model.

RESULTS

Of the 3826 patients, 2511 (65.6 %) developed mild leucopenia (grade 1-2) and 807 (21.1 %) developed severe leucopenia (grade 3-4) during treatment; 508 (13.3 %) did not. A multivariate Cox model that included leucopenia determined that the hazard ratios (HR) of death for patients with mild and severe leucopenia were 0.69 [95 % confidence interval (95 %CI) 0.56-0.85, p < 0.001] and 0.75 (95 %CI 0.59-0.95, p = 0.019), respectively; the HR of distant metastasis for patients with mild and severe leucopenia were 0.77 (95 %CI 0.61-0.96, p = 0.023) and 0.99 (95 %CI 0.77-1.29, p = 0.995), respectively. Leucopenia had no effect on locoregional relapse.

CONCLUSIONS

Our results indicate that mild leucopenia during chemoradiotherapy is associated with improved overall survival and distant metastasis-free survival in ANPC. Mild leucopenia may indicate appropriate dosage of chemotherapy. We can identify the patients who may benefit from chemotherapy if they experienced leucopenia during the treatment. Prospective trials are required to assess whether dosing adjustments based on leucopenia may improve chemotherapy efficacy.

Myelotoxicity of carboplatin is increased in vivo in db/db mice, the animal model of obesity-associated diabetes mellitus

PURPOSE

Some authors observed increased carboplatin-associated myelotoxicity in obese patients which was exclusively attributed to elevated AUC. To investigate the potential contribution of functional changes of cells primarily responsible for myelopoiesis, granulocyte-macrophage progenitors (CFU-GM) were studied in obesity-associated diabetes mellitus (DMT2).

METHODS

The most frequently used animal model of human obesity with DMT2 is db/db mouse. Cellularity, frequency of CFU-GM and total CFU-GM content of femoral bone marrow were measured after 100 mg/kg dose of carboplatin in vivo. To exclude influence of pharmacokinetic changes, direct toxicity of carboplatin on CFU-GM was also determined in vitro and was compared with other anticancer agents, namely doxorubicin, 5-fluorouracil and 4-thiouridylate.

RESULTS

After intraperitoneal administration of carboplatin, each measured characteristics of bone marrow function was more significantly suppressed and the induced neutropenia was more serious in db/db mice than in the controls. The increased myelotoxicity seemed to be a direct effect on myeloid progenitor cells since their increased in vitro sensitivity was found in db/db mice. This was not specific for carboplatin, a similar double to fivefold increase in myelotoxicity of each cytotoxic drug with different mechanism of action was observed. Four-thiouridylate, a promising antileukemic molecule with good therapeutic index, was by far the least toxic for CFU-GM of db/db mice.

CONCLUSIONS

A serious disorder of CFU-GM progenitors was suggested in obese mice with DMT2, which eventually might lead to more severe myelotoxicity and neutropenia. Weight loss and normalization of glucose homeostasis may be important before chemotherapy of malignant diseases in obesity with DMT2.

The impact of delayed chemotherapy on its completion and survival outcomes in stage II colon cancer patients

Background

Delayed chemotherapy is associated with inferior survival in stage III colon and stage II/III rectal cancer patients, but similar studies have not been performed in stage II colon cancer patients. We investigate the association between delayed and incomplete chemotherapy, and the association of delayed chemotherapy with survival in stage II colon cancer patients.

Patients and Methods

Patients (age ≥66) diagnosed as stage II colon cancer and received chemotherapy from 1992 to 2005 were identified from the linked SEER–Medicare database. The association between delayed and incomplete chemotherapy was assessed using unconditional and conditional logistic regressions. Survival outcomes were assessed using stratified Cox regression based on propensity score matched samples.

Results

4,209 stage II colon cancer patients were included, of whom 73.0% had chemotherapy initiated timely (≤2 months after surgery), 14.7% had chemotherapy initiated with moderate delay (2–3 months), and 12.3% had delayed chemotherapy (≥3 months). Delayed chemotherapy was associated with not completing chemotherapy (adjusted odds ratio (OR): 1.33 (95% confidence interval: 1.11, 1.59) for moderately delayed group, adjusted OR: 2.60 (2.09, 3.24) for delayed group). Delayed chemotherapy was associated with worse survival outcomes (hazard ratio (HR): 1.75 (1.29, 2.37) for overall survival; HR: 4.23 (2.19, 8.20) for cancer-specific survival).

Conclusion

Although the benefit of chemotherapy is unclear in stage II colon cancer patients, delay in initiation of chemotherapy is associated with an incomplete chemotherapy course and poorer survival, especially cancer-specific survival. Causal inference in the association between delayed initiation of chemotherapy and inferior survival requires further investigation.

Neutropenia as a potential pharmacodynamic marker for docetaxel-based chemotherapy in men with metastatic castration-resistant prostate cancer

BACKGROUND

Docetaxel clearance appears increased in men who are castrated. Neutropenia in cycle 1 may be a pharmacodynamic marker for docetaxel, which may enable tailored dosing in metastatic castration-resistant prostate cancer (mCRPC).

PATIENTS AND METHODS

The association of cycle 1 neutropenia with overall survival (OS) was examined post hoc in a randomized phase II trial of 221 men with mCRPC who received docetaxel-prednisone combined with placebo or AT-101 (bcl-2 inhibitor); weekly blood cell counts were performed during the first cycle. Patients from both arms were combined because no outcome and toxicity differences were observed. OS was calculated from randomization by the Kaplan-Meier method, and Cox proportional hazards regression models were used to estimate the association with OS.

RESULTS

The difference in OS between men with day 8 ≥grade 3 neutropenia and those with ≤grade 2 neutropenia was significant after adjusting for trial stratification factors, pain, and performance status (hazard ratio [HR] 0.64; 2P = .048). Results were similar for logarithmic neutrophil counts adjusted for the risk group based on anemia, visceral metastasis, progression by bone scan and pain (HR 1.18; 2P = .07) for stratification factors (HR 1.20; 2P = .052) or both (HR, 1.20; 2P = .046). Men with ≥grade 3 neutropenia and ≥30% prostate-specific antigen level decline by day 90 had improved OS compared with men exhibiting neither (HR 0.51; 2P = .014).

CONCLUSIONS

For patients with mCRPC who received docetaxel, ≥grade 3 neutropenia on day 8 was prognostic for improved OS, which suggests its utility as a pharmacodynamic marker, in this hypothesis-generating analysis. Exploration of dose escalation of docetaxel to attain ≥grade 3 neutropenia on day 8 may be warranted.

Tailored chemotherapy doses based on toxicity in breast cancer result in similar quality of life values, irrespective of given dose levels

BACKGROUND

From March 1994 to March 1998, breast cancer patients (an estimated relapse risk with 70% or more within five years with standard therapy) were randomised to treatment with tailored fluorouracil, epirubicin, and cyclophosphamide (FEC) therapy or FEC followed by marrow-supported high dose therapy in the Scandinavian Breast Group 9401 study. The aim of the present paper was to investigate differences in toxicity and eight health-related quality of life (HRQoL) variables (physical functioning, role functioning, emotional functioning, social functioning, cognitive functioning, fatigue, nausea-vomiting, and global quality of life) between women in the six dose steps used in the tailored and granulocyte colony stimulating factor supported FEC-arm at the assessment point 16 weeks after random assignment to treatment.

METHODS

The European Organization and Treatment of Cancer Quality of Life Questionnaire EORTC QLQ-C30 were mailed to the patients.

RESULTS

A total of 157 (87%) in the tailored FEC-group responded to the questionnaire within the time frame 16 weeks after inclusion in the study. Overall, toxicity was low, reaching grade 1-2 also in the higher dose steps. There were no overall differences between the dose steps on any of the tested HRQoL variables. Patients at dose step 4 scored statistically significantly higher on physical functioning than patients at dose step 1 (p = 0.022) and compared to those at dose step 2 (p = 0.014). Patients at dose steps -2 and -1 (combined to one group) reported statistically significantly higher mean scores on cognitive functioning than patients at dose step 1 (p = 0.022).

CONCLUSION

Patients who received higher doses, based on the tailored dosing strategy, did not seem to have worse HRQoL than those who had lower doses.

Dose-tailoring of FEC adjuvant chemotherapy based on leukopenia is feasible and well tolerated. Toxicity and dose intensity in the Scandinavian Breast Group phase 3 adjuvant Trial SBG 2000-1

The SBG 2000-1 trial is a randomised study that investigates if dose-tailored adjuvant FEC therapy based on the individual's leukocyte nadir value can improve outcome. The study has included 1535 women with medium and high-risk breast cancer.

PATIENTS AND METHODS

After a first standard dosed FEC course (5-fluorouracil 600 mg/m(2), epirubicin 60 mg/mg(2) and cyclophosphamide 600 mg/m(2)), patients who did not reach leukopenia grade III or IV were randomised to standard doses (group standard) or doses tailored to achieve grade III leukopenia (group tailored) at courses 2-7. Patients who achieved leukopenia grade III or more after the first course were not randomised but continued on standard doses (group registered).

RESULTS

Both planned and actually delivered number of courses (seven) were the same in all three arms. The relative dose intensity was increased by a factor of 1.31 (E 1.22, C 1.43) for patients in the tailored arm compared to the expected on standard dose. Ninety percent of the patients in the tailored arm achieved leukopenia grade III-IV compared with 29% among patients randomised to standard dosed therapy. Dose tailoring was associated with acceptable acute non-haematological toxicity with more total alopecia, nausea, vomiting and fatigue.

CONCLUSION

Dose tailoring according to leukopenia was feasible. It led to an increased dose intensity and was associated with acceptable excess of acute non-haematological toxicity.

Dose dense cyclophosphamide, methotrexate, fluorouracil is feasible at 14-day intervals: a pilot study of every-14-day dosing as adjuvant therapy for breast cancer

PURPOSE

Cyclophosphamide/methotrexate/fluorouracil (CMF) is a proven adjuvant option for patients with early-stage breast cancer. Randomized trials with other regimens demonstrate that dose-dense (DD) scheduling can offer greater efficacy. We investigated the feasibility of administering CMF using a DD schedule.

PATIENTS AND METHODS

Thirty-eight patients with early-stage breast cancer were accrued from March 2008 through June 2008. They were treated every 14 days with C 600, M 40, F 600 (all mg/m2) with PEG-filgrastim (Neulasta®) support on day 2 of each cycle. The primary endpoint was tolerability using a Simon's 2-stage optimal design. The design would effectively discriminate between true tolerability (as protocol-defined) rates of ≤ 60% and ≥ 80%.

RESULTS

The median age was 52-years-old (range, 38-78 years of age). Twenty-nine of the 38 patients completed 8 cycles of CMF at 14-day intervals.

CONCLUSION

Dose-dense adjuvant CMF is tolerable and feasible at 14-day intervals with PEG-filgrastim support.

Adjuvant cyclophosphamide, methotrexate, and fluorouracil in premonopausal patients with node-positive breast cancer: indirect comparison of dose and schedule in DBCG trials 77, 82, and 89

A significant reduction in the risk of recurrence and death was achieved three decades ago with adjuvant chemotherapy in patients with operable breast. The major pivotal trials used oral cyclophosphamide (C) days 1-14 with intravenous methotrexate (M) and fluorouracil (F) on days 1 and 8, repeated every 28 days. The classical CMF has later been modified as concerns dose and schedule, without formal comparisons in randomised trials between the classical CMF and the modifications.

MATERIAL AND METHODS

Classical CMF was used in the first adjuvant chemotherapy trial performed by the Danish Breast Cancer Cooperative Group (DBCG), and two succeeding randomised trials in premenopausal patients with node positive breast cancer used three-weekly or four-weekly intravenous CMF in one of the treatment arms.

RESULTS

Between November 1977 and January 2001 these trials included 2 213 patients who in addition to surgery and radiotherapy received CMF. Ten-year disease-free survival (DFS) rates were 48% following classical CMF, 45% following four-weekly and 47% following three-weekly CMF. Major differences in patient characteristics were observed across these three cohorts, and a multivariate analysis was performed adjusting for the known prognostic factors. In the adjusted analysis a 30% increase in the risk of recurrence was observed for two the intravenous regimens as compared to classical CMF. As concerns survival a significant 40% increase in the risk of death was observed with the four-weekly regimen, while a similar risk of death was observed with the three-weekly intravenous. Classical CMF was associated with a higher risk of amenorrhoea, and this may at least in part explain an observed interaction between age and efficacy.

DISCUSSION

This cross trial comparison suggests a detrimental effect in premenopausal patients with node positive breast cancer when shifting from classical CMF to intravenous regimens with lower dose-intensity. Caution is required in the interpretation of these results due to the non-experimental study design.

Dose calculation of anticancer drugs

BACKGROUND

Anticancer drugs are characterized by a narrow therapeutic window and significant inter-patient variability in therapeutic and toxic effects. Current body surface area (BSA)-based dosing fails to standardize systemic anticancer drug exposure and other alternative dosing strategies also have their limitations. Just as important as the initial dose selection is the subsequent dose revision to ensure the dose is correct.

OBJECTIVE

To provide an insight into the different dose individualization and dose adjustment methods, their feasibility and applicability in daily oncology practice and to suggest a practical framework for dose calculation and a basis for future research.

METHODS

Review of relevant literature related to dose calculation of anticancer drugs.

RESULTS

Strategies using clinical parameters, genotype and phenotype markers, and therapeutic drug monitoring all have potential and each has a role for specific drugs. However, no one method is a practical dose calculation strategy for many or all drugs.

CONCLUSION

Given that BSA-dosing leads to significant underdosing it is not reasonable to use this as the sole method of dose calculation. Because of wide disparity in individual patient characteristics and elimination mechanisms, we are unlikely to find the 'Holy Grail' of a single individualized dosing strategy for every patient and anticancer drug in the near future. We propose a pragmatic, although invalidated system for initial dose calculation using dose clusters and structured subsequent dose revision based on treatment-related toxicities and therapeutic drug monitoring. These models need to be tested in clinical trials.

Impact of a reduced dose intensity of adjuvant anthracycline based chemotherapy in a population-based cohort of stage I-II breast cancers

Background:

Reductions in the dose intensity (DI) of adjuvant anthracycline-based chemotherapy in early stage breast cancer are frequently required due to treatment toxicity or poor tolerance, but the implications of a minimal reduction in DI on clinical outcome remain uncertain.

Patients and methods:

Women with stage I–II breast cancer treated with adjuvant adriamycin and cyclophosphamide (AC) from 1990–95 were identified in a provincial breast cancer database. Cases were classified into four cohorts: (1) all cycles delivered at full dose and on time; (2) one single dose reduction or dose delay; (3) >1 dose reduction or dose delay; (4) <2 cycles of chemotherapy delivered.

Results:

484 eligible cases were identified (cohort (1): n = 268; (2): n= 88; (3): n= 89; (4) n= 39). Slight imbalances in lymph node status (p=0.05) and adjuvant hormonal therapy (p=0.05) were observed between the cohorts. Fifty-five per cent (267/484) of the patients had node-positive disease and 33% (158/484) were ER+. 45% of cases had a reduction in DI. With a median follow-up of 9.6 years, there were no significant differences in relapse-free survival (p=0.94), breast cancer-specific survival (p=0.87) or overall survival (p=0.86) between the four cohorts. Outcomes were independent of hormone receptor status.

Conclusions:

Although toxicity related reductions in the DI of adjuvant AC chemotherapy for early stage breast cancer are common, they did not appear to significantly impact on clinical outcomes in this population-based cohort of women with stage I–II breast cancers.

Does chemotherapy-induced neutropaenia result in a postponement of adjuvant or neoadjuvant regimens in breast cancer patients? Results of a retrospective analysis

In 2005, 224 patients received adjuvant/neoadjuvant chemotherapy for breast cancer in a single institution according to daily practices. Regimens consisted of epirubicin-based chemotherapy (FEC100, four or six cycles), or three cycles of FEC100 followed by three cycles of docetaxel. An absolute blood count was carried out every 3 weeks, 1–3 days before planned chemotherapy cycle. Overall, 1238 cycles were delivered. An absolute neutrophil count (ANC) <1.5 × 10⁹ l⁻¹ before planned chemotherapy was found in 171 cycles. Of these, 130 cycles (76%) were delivered as planned regardless of whether ANC levels recovered, and 41 (24%) were delayed. None of these patients developed a febrile neutropaenia. Haematopoietic support (granulocyte colony-stimulating factor (G-CSF)) was required in 12 cycles. We found that the majority of patients with an ANC <1.5 × 10⁹ l⁻¹ before planned chemotherapy received planned doses, without complications and need for G-CSF.

Effects of a treatment gap during adjuvant chemotherapy in node-positive breast cancer: results of International Breast Cancer Study Group (IBCSG) Trials 13-93 and 14-93

BACKGROUND

The International Breast Cancer Study Group (IBCSG) conducted two complementary randomized trials to assess whether a treatment-free gap during adjuvant chemotherapy influenced outcome.

PATIENTS AND METHODS

From 1993 to 1999, IBCSG Trials 13-93 and 14-93 enrolled 2215 premenopausal and postmenopausal women with axillary node-positive, operable breast cancer. All patients received cyclophosphamide (Cytoxan, C) plus either doxorubicin (Adriamycin, A) or epirubicin (E) for four courses followed immediately (No Gap) or after a 16-week delay (Gap) by classical cyclophosphamide, methotrexate, and fluorouracil (CMF) for three courses. The median follow-up was 7.7 years.

RESULTS

The Gap and No-Gap groups had similar disease-free survival (DFS) and overall survival (OS). No identified subgroup showed a statistically significant difference, but exploratory subgroup analysis noted a trend towards decreased DFS for Gap compared with No Gap for women with estrogen receptor (ER)-negative tumors not receiving tamoxifen, especially evident during the first 2 years.

CONCLUSIONS

A 16-week gap between adjuvant AC/EC and CMF provided no benefit and may have increased early recurrence rates in patients with ER-negative tumors.

Long-term follow-up of the SBG 9401 study comparing tailored FEC-based therapy versus marrow-supported high-dose therapy

BACKGROUND

The purpose was to investigate adjuvant marrow-supportive high-dose chemotherapy compared with an equitoxicity-tailored comparator arm.

PATIENTS AND METHODS

Five hundred and twenty-five women below the age of 60 years with operated high-risk primary breast cancer were randomised to nine cycles of granulocyte colony-stimulating factor supported and individually tailored FEC (5-fluorouracil, epirubicin, cyclophosphamide), (n = 251) or standard FEC followed by marrow-supported high-dose therapy with CTCb (cyclophosphamide, thiotepa, carboplatin) therapy (n = 274), followed by locoregional radiotherapy and tamoxifen for 5 years.

RESULTS

There were 104 breast cancer relapses in the tailored FEC group versus 139 in the CTCb group (double triangular method by Whitehead, P = 0.046), with a median follow-up of all included patients of 60.8 months. The event-free survival demonstrated 121 and 150 events in the tailored FEC- and CTCb group, respectively [P = 0.074, hazard ratio (HR) 0.804, 95% confidence interval (CI) 0.633-1.022]. Ten patients in the tailored FEC regimen developed acute myeloid leukaemia (AML)/myelodysplasia (MDS). One hundred deaths occurred in the tailored FEC group and 121 in the CTCb group (P = 0.287, HR 0.866, 95% CI 0.665-1.129).

CONCLUSION

The update of this study shows an improved outcome linked to the tailored FEC treatment in relation to breast cancer relapse, but also an increased incidence of AML/MDS.

Timing of adjuvant chemotherapy initiation after surgery for stage III colon cancer

BACKGROUND

An important advance in medical oncology has been the use of adjuvant chemotherapy for lymph node-positive colon cancer. However, to the authors' knowledge, the effect of the interval between surgery and the initiation of chemotherapy on survival has not been investigated.

METHODS

The authors analyzed predictors and outcomes of time intervals to treatment after surgery among patients older than 65 years who were diagnosed with stage III colon cancer between 1992 and 1999 using Surveillance, Epidemiology, and End Results (SEER)-Medicare data. Linear and logistic regression analyses were used to model predictors of delay, and Cox proportional hazards models were used to analyze the impact of treatment timing on survival.

RESULTS

Among 4382 patients with colon cancer, 1122 patients (26%) began adjuvant chemotherapy within 1 month, 2391 patients (55%) began adjuvant chemotherapy in 1 to 2 months, 454 patients (10%) began adjuvant chemotherapy in 2 to 3 months, and 415 patients (9%) began adjuvant chemotherapy >/=3 months after surgery. Intervals of >/=3 months (delay) were associated with older age, increased comorbid conditions, well/moderately differentiated grade, and being unmarried. Colon cancer-specific mortality was associated with a delay in the initiation of chemotherapy (hazards ratio [HR], 1.48; 95% confidence interval [95% CI], 1.15-1.92), advanced age, increased comorbidity, poorly differentiated tumor grade, the presence of >/=4 positive lymph nodes, and undergoing surgery in a nonteaching hospital. All-cause mortality was associated with intervals >2 months between surgery and chemotherapy (2 to 3 months: HR, 1.41; 95% CI, 1.15-1.74; >/=3 months: HR, 1.62; 95% CI, 1.31-1.99) compared with <1 month.

CONCLUSIONS

In the older population that was studied, only 9% of patients initiated adjuvant chemotherapy >3 months after the date of curative surgery. However, delay in initiation was associated with both cancer-specific and all-cause mortality. Determining whether these results were because of chemotherapy timing or other associated factors will require further study.

Tolerability and safety of classic cyclophosphamide, methotrexate, and fluorouracil treatment in Japanese patients with early breast cancer

BACKGROUND

Few reports have addressed the feasibility and safety of classic Cyclophosphamide, Methotrexate, and Fluorouracil (CMF) therapy in Japanese female breast cancer patients.

METHODS

Twenty-four Japanese patients who received classic CMF, identical to the originally described treatment regimen were studied in terms of treatment dose, treatment delay, and toxicity.

RESULTS

Classic CMF was not discontinued in any of the cases. The median delay in treatment was 14 days, and the mean administered dose of cyclophosphamide was 98.2% of the planned dose. None of the patients suffered severe side-effects such as febrile neutropenia; however, in 22 patients in whom the effect of CMF on hair loss could be assessed, 7 (31.8%) had to wear hats or wigs.

CONCLUSIONS

Classic CMF is a feasible and safe regimen in Japanese breast cancer patients. In Japan, this regimen is still available for some specific groups of early breast cancer patients.

Predictors of reduced dose intensity in patients with early-stage breast cancer receiving adjuvant chemotherapy

BACKGROUND

This retrospective study was undertaken to define risk factors for reductions in dose intensity of adjuvant chemotherapy in women with early stage breast cancer (ESBC).

METHODS

A nationwide survey of 190 community oncology practices was conducted between 1998 and 2002 with data collected retrospectively on 3,707 patients treated with adjuvant chemotherapy for ESBC. End points included reductions in dose intensity, delivered relative dose intensity (RDI) <85%, and the incidence of chemotherapy dose delays >/=7 days and dose reduction >/=15%. Demographic and clinical characteristics, incidence of febrile neutropenia (FN), and patterns of use of granulocyte colony-stimulating factor (G-CSF) were also assessed.

RESULTS

Average RDI for all regimens was 88%, with 30% of patients receiving <85% of standard for their regimen. Seventeen percent of the reduction in average RDI was planned from the start of therapy, and 13% was unplanned. In univariate analysis, significant predictors of reduced RDI were: age >/=65 years (41%, P < 0.001), body surface area (BSA) >2 m(2) (37%, P < 0.001), negative lymph nodes (33%, P < 0.001), FN (36%, P = 0.013), and comorbidities (40%, P = 0.013), particularly renal disease (86%, P = 0.004). Dose reduction was less with prophylactic G-CSF (24%, P < 0.001). In multivariate analysis, significant independent predictors of reduced RDI included: advanced age, greater BSA, comorbidities, anthracycline-based regimens, a 28-day schedule and FN, while primary G-CSF prophylaxis was associated with a significant reduction in risk.

CONCLUSION

A significant proportion of patients with potentially curable ESBC continue to experience planned and unplanned reductions in RDI.

Adjuvant chemotherapy for breast cancer—“one fits all”?

Adjuvant breast cancer therapy and early diagnosis will improve breast cancer outcome. The Eurocare studies have demonstrated large differences in breast cancer incidence and mortality in different regions and countries and underlined the importance of access and quality in the management of early disease. So far, the very important survival gains by adjuvant therapy have been obtained by "one fits all"--like strategies, resulting in therapy in vain for many patients and unnecessary therapy for large cohorts. Present adjuvant strategies have focused on group statistical risk analysis, mainly using tumour stage, histological grade and receptor status. Five retrospective studies have revealed a worse outcome for patients receiving adjuvant chemotherapy without toxicity. In one of these studies the breast cancer survival was improved by 10% for patients who received grade 2/3 neutropenia; this is equivalent to the described survival gains by the addition of anthracyclines and taxanes to cyclophosphamide, methotrexate, 5-fluorouracil (CMF) combinations. Prospectively, this has been explored in the Scandinavian Breast Group (SBG) 9401-, SBG 2000-1- and presently in the SBG 2004-1 studies using tailored chemotherapy dosage strategies, aimed at avoiding under-dosage and diminishing acute side effects. For the future, we need several predictive factors for therapy, allowing better and more tailored therapy selections for individuals at risk. The present explorations of tumour RNA expression profiles are most likely to be useful in identifying therapy-predictive profiles for these individuals. Pharmacokinetic and pharmacodynamic data reveal marked differences in effect and tolerance of used drugs. The development of single nucleotide polymorphism technology are also likely to be important for optimising dosing strategies, aiming and increasing the effect, as well as decreasing toxicity. Taken together these strategies will be very different from the present "one fits all" concept.

Model Describing the Relationship Between Pharmacokinetics and Hematologic Toxicity of the Epirubicin-Docetaxel Regimen in Breast Cancer Patients

Purpose

The aims of the present study were (1) to characterize the pharmacokinetics of both component drugs and (2) to describe the relationship between the pharmacokinetics and the dose-limiting hematologic toxicity for the epirubicin (EPI)/docetaxel (DTX) regimen in breast cancer patients.

Patients and Methods

Forty-four patients with advanced disease received EPI and DTX every 3 weeks for up to nine cycles. The initial doses (EPI/DTX) were 75/70 mg/m2. Based on leukocyte (WBC) and platelet counts, the subsequent doses were, stepwise, either escalated (maximum, 120/100 mg/m2) or reduced (minimum, 40/50 mg/m2). Hematologic toxicity was monitored in all patients, whereas pharmacokinetics was studied in 16 patients. A semiphysiological model, including physiological parameters as well as drug-specific parameters, was used to describe the time course of WBC count following treatment.

Results

In the final pharmacokinetic model, interoccasion variability was estimated to be less than interindividual variability in the clearances for both drugs. The sum of the individual EPI and DTX areas under concentration-time curve correlated stronger to WBC survival fraction than did the corresponding sum of doses. A pharmacokinetic-pharmacodynamic (PK-PD) model with additive effects of EPI and DTX could adequately describe the data.

Conclusion

The final PK-PD model might provide a tool for calculation of WBC time course, and hence, for prediction of nadir day and duration of leukopenia in breast cancer patients treated with the EPI/DTX regimen.

Dose and schedule as determinants of outcomes in chemotherapy for breast cancer

Many cytotoxic agents for the adjuvant treatment of breast cancer are available, but they have produced only modest results, even when the tumor burden is low. This relative lack of efficacy may be attributed, in part, to the nonspecificity of the current regimens. Additionally, there is evidence that the chemotherapy doses used in clinical practice are not optimal, which potentially compromises the outcomes when the thresholds of dose intensity are not reached. Variations in treatment underscore the need to return to the basics of chemotherapy administration: dose, schedule, concentration threshold, and therapeutic index. In patients with metastatic breast cancer a clear dose-response curve has been shown with some agents, including anthracyclines. The E-max model, which in its simplest form assumes a direct relation between the dose of a drug and its effect, may be used to improve dosing in the adjuvant treatment of breast cancer. Consistent with this model, threshold effects have been observed in treatment with both anthracyclines and paclitaxel for breast cancer. There is also evidence that using dose-dense schedules may produce better outcomes with some regimens. Maintaining chemotherapy agents at full dose on schedule is crucial to treatment success, especially in adjuvant therapy. Consequently, treatment practices should use both dose intensity and dose compression to increase the likelihood of positive outcomes in patients with breast cancer.

Best use of adjuvant systemic therapies II, chemotherapy aspects: dose of chemotherapy-cytotoxicity, duration and responsiveness

The overall survival improvement by adjuvant chemotherapy is partly related to patient age, stage and chemotherapy regimens used. Too low dose dose-intensities or total doses will result in inferior outcomes. Conventional dose escalations above standard doses will not be beneficial for doxorubicin or cyclophosphamide, while an epirubicin dose of 90-100mg/m2 given every third week in polychemotherapy regimens results in overall survival gains. The issue is more complex, while retrospective analysis of adjuvant regimens have revealed inferior outcomes for patients receiving standard chemotherapy doses and regimens without toxicity. Most cytostatics demonstrate a marked inter-individual variation in different pharmacokinectic parameters, not compensated for by dosage based on body surface area. These facts have partly been the basis for the randomised Scandinavian Breast Group (SBG) studies SBG 9401 and 2000-1, respectively, using tailored dosage strategies aiming at interpatient equivalent dosage. Randomised studies using marrow supported-high dose strategies have so far not been demonstrated to result in overall survival improvements. G-CSF (granulocyte-colony stimulating factor) and dose-dense paclitaxel containing regimens have resulted in a small but significant survival gain compared with conventional three weekly regimens, challenging the present dogma of conventional three-four weekly scheduling, based on normal tissue side-effects rather than tumour biological considerations. The recent microarray based studies demonstrated marked inter-patient variability in gene expression and underline the potential for better patient selection and more tailored therapy strategies.

Racial Disparity in the Dose and Dose Intensity of Breast Cancer Adjuvant Chemotherapy

PURPOSE

The purpose of this study was to investigate the impact of race and obesity on dose and dose intensity of adjuvant chemotherapy.

METHODS

We abstracted data on patient/tumor characteristics, treatment course, physicians' intention to give a first cycle dose reduction, and reasons for dose reductions/delays from oncology records of 489 women treated from 1985 to 1997 in 10 treatment sites in two geographical regions. Administered doses and dose intensity were compared to standard regimens. Multivariate regression models determined the impact of race and body mass index (BMI) on dose proportion (actual:expected doses) and relative dose intensity (RDI) controlling for patient characteristics, comorbidity, chemotherapy regimen, site, and year of treatment. Logistic regressions explored race and BMI versus use of first cycle dose reductions.

RESULTS

African-Americans received lower chemotherapy dose proportion and RDI than whites (0.80 vs. 0.85, p = 0.03 and 0.76 vs. 0.80, p = 0.01). In multivariate analyses, dose proportion was 0.09 lower (p = 0.002), and RDI was 0.10 (p < 0.001) lower in non-overweight African-Americans than whites. Obesity was associated with lower dose proportion (p < 0.01) and RDI (p < 0.03). Race and BMI were independently associated with first cycle dose reductions. Non-overweight African-Americans (p < 0.05) and overweight and obese African-American and white women (p < 0.001) were more likely to have first cycle dose reductions than non-overweight whites.

CONCLUSION

We identified systematic differences in the administration of chemotherapy given to African-Americans and to overweight and obese women. These differences may contribute to documented disparities in outcome.

Are medical oncologists biased in their treatment of the large woman with breast cancer?

PURPOSE

Obesity and breast cancer are common conditions that often coexist. Concerns of relative overdosing of chemotherapy in the large cancer patient have led clinicians to apply empiric dose reductions, 'cap' the body surface area (BSA) at 2 m2, or use ideal rather than actual body weight to calculate BSA. There are no data supporting or refuting these practices and their prevalence is unknown. We sought to determine the distribution of body size and prevalence of obesity in the breast cancer population of our cancer centre, and to determine clinician chemotherapy dosing practices in the era of modern adjuvant chemotherapy.

PATIENTS AND METHODS

Women with invasive breast cancer receiving systemic therapy at our institution between 1980 and 1998 were identified and their recorded height and weight were used to calculate BSA and body mass index (BMI). We reviewed the first cycle adjuvant chemotherapy dosing practices from 1990-1998. The ideal dose of chemotherapy was calculated based on calculated BSA, and then contrasted with the actual dose received at cycle one. Discrepancies were recorded and categorized, using the largest single drug reduction if more than one drug was reduced.

RESULTS

Mean BMI in the systemic therapy population was 26.4 +/- 5.3 kg/m2, 54% were overweight, 2% severely obese and 18% moderately so. Their mean BSA was 1.7 +/- 0.2 m2 and only 5% had a BSA > or = 2 m2. In the adjuvant chemotherapy subgroup, most patients received > or = 85% of their ideal dose. The mean dose reduction was 5.3 +/- 11.3% versus 9.9 +/- 11.3% in the BSA < 2 and > or = 2 m2 groups, respectively (p = 0.02), and 4.3 +/- 8.2% versus 6.7 +/- 13.1% in the BMI < 25 and > or = 25 kg/m2 groups, respectively (p = 0.008). While only 24% of chemotherapy dose reductions of > or = 15% were in the BSA > or = 2 m2 group, 76% were in the BMI > or = 25 kg/m2 group.

CONCLUSIONS

Obesity is prevalent in this breast cancer population. BSA is not a sensitive index of large body size. We consistently detected more frequent empiric dose reductions at cycle one of adjuvant chemotherapy, with reductions of greater magnitude in the largest women (BSA > or = 2 m2) and those who were overweight (BMI > or = 25 kg/m2).

Tailored fluorouracil, epirubicin, and cyclophosphamide compared with marrow-supported high-dose chemotherapy as adjuvant treatment for high-risk breast cancer: a randomised trial. Scandinavian Breast Group 9401 study

BACKGROUND

Chemotherapy drug distribution varies greatly among individual patients. Therefore, we developed an individualised fluorouracil, epirubicin, cyclophosphamide (FEC) regimen to improve outcomes in patients with high-risk early breast cancer. We then did a randomised trial to compare this individually tailored FEC regimen with conventional adjuvant chemotherapy followed by consolidation with high-dose chemotherapy with stem-cell support.

METHODS

525 women younger than 60 years of age with high-risk primary breast cancer were randomised after surgery to receive nine cycles of tailored FEC to haematological equitoxicity with granulocyte colony-stimulating factor (G-CSF) support (n=251), or three cycles of FEC at standard doses followed by high-dose chemotherapy with cyclophosphamide, thiotepa, and carboplatin (CTCb), and peripheral-blood stem-cell or bone-marrow support (n=274). Both groups received locoregional radiation therapy and tamoxifen for 5 years. The primary outcome measure was relapse-free survival, and analysis was by intention to treat.

FINDINGS

At a median follow-up of 34.3 months, there were 81 breast-cancer relapses in the tailored FEC group versus 113 in the CTCb group (double triangular method p=0.04). 60 deaths occurred in the tailored FEC group and 82 in the CTCb group (log-rank p=0.12). Patients in the CTCb group experienced more grade 3 or 4 acute toxicity compared with the tailored FEC group (p<0.0001). Two treatment-related deaths (0.7%) occurred in the CTCb group. Six patients in the tailored FEC group developed acute myeloid leukaemia and three developed myelodysplastic syndrome.

INTERPRETATION

Tailored FEC with G-CSF support resulted in a significantly improved relapse-free survival and fewer grade 3 and 4 toxicities compared with marrow-supported high-dose chemotherapy with CTCb as adjuvant therapy of women with high-risk primary breast cancer.

Leucocyte nadir as a marker for chemotherapy efficacy in node-positive breast cancer treated with adjuvant CMF

The purpose of this study was to examine the association between the leucocyte nadir and prognosis in breast cancer patients receiving adjuvant chemotherapy consisting of cyclophosphamide, methotrexate and fluorouracil (CMF). Three hundred and sixty-eight patients with node-positive breast cancer without distant metastases were treated with six cycles of adjuvant CMF. Some patients (n = 60) also received tamoxifen. All patients underwent surgery and received radiotherapy to the axillary and supraclavicular lymph nodes and the chest wall. The effect of leucopenia caused by CMF on distant disease-free survival (DDFS) and overall survival (OS) was assessed. A low leucocyte nadir during the chemotherapy was associated with a long DDFS in univariate analysis when tested as a continuous variable (the relative risk (RR) 1.3, 95% confidence interval (CI) 1.04-1.06, P = 0.02). Similarly, when the leucocyte nadir count was divided into tertiles, the patients who had the highest nadir values during the six-cycle treatment had worst outcome (RR 1.6, 95% CI 1.07-2.5, P = 0.02). However, in a multivariate analysis only the number of affected lymph nodes, tumour size, progesterone receptor status, surgical procedure, age and adjuvant tamoxifen therapy retained prognostic significance, whereas the leucocyte nadir count did not. A low leucocyte nadir during the adjuvant CMF chemotherapy is associated with favourable DDFS and it may be a useful biological marker for chemotherapy efficacy.