Risk of acute leukemia following epirubicin-based adjuvant chemotherapy: a report from the National Cancer Institute of Canada Clinical Trials Group

Mitigating long-term and delayed adverse events associated with cancer treatment: implications for survivorship

Despite the importance of chemotherapy-associated adverse events in oncology practice and the broad range of interventions available to mitigate them, limited systematic efforts have been made to identify, critically appraise and summarize the totality of evidence on the effectiveness of these interventions. Herein, we review the most common long-term (continued beyond treatment) and late or delayed (following treatment) adverse events associated with chemotherapy and other anticancer treatments that pose major threats in terms of survival, quality of life and continuation of optimal therapy. These adverse effects often emerge during and continue beyond the course of therapy or arise among survivors in the months and years following treatment. For each of these adverse effects, we discuss and critically evaluate their underlying biological mechanisms, the most commonly used pharmacological and non-pharmacological treatment strategies, and evidence-based clinical practice guidelines for their appropriate management. Furthermore, we discuss risk factors and validated risk-assessment tools for identifying patients most likely to be harmed by chemotherapy and potentially benefit from effective interventions. Finally, we highlight promising emerging supportive-care opportunities for the ever-increasing number of cancer survivors at continuing risk of adverse treatment effects.

Preferential Binding of Epirubicin Hydrochloride with Single Nucleotide Mismatched DNA and Subsequent Sequestration by a Mixed Micelle

Targeting mismatched base pairs containing DNA using small molecules and exploring the underlying mechanism involved during the binding interactions is one of the fundamental aspects of drug design. These molecules in turn are used in nucleic acid targeted therapeutics and cancer diagnosis. In this work, we systematically delineate the binding of the anticancer drug, epirubicin hydrochloride (EPR) with 20-mer duplex DNA, having both natural nucleobase pairing and thermodynamically least stable non-Watson-Crick base pairing. From the thermal denaturation studies, we observed that EPR can remarkably enhance the thermal stability of cytosine-cytosine (CC) and cytosine-thymine (CT) mismatched (MM) DNA over other 20-mer duplex DNA. From steady-state fluorescence spectroscopy and isothermal titration calorimetry studies, we concluded that EPR binds strongly with the mismatched duplex DNA through the intercalation binding mode. The interaction of EPR and duplex DNA has also been monitored at a single molecular resolution using fluorescence correlation spectroscopy (FCS). Dynamic quantitates such as diffusion coefficients and hydrodynamic radii obtained from an FCS study along with association and dissociation rate constants estimated from intensity time trace analyses further substantiate the stronger binding affinity of EPR to the thermally less stable mismatched DNA, formed by the most discriminating nucleobase (viz. cytosine). Additionally, we have shown that EPR can be sequestered from nucleic acids using a mixed micellar system of an anionic surfactant and a triblock copolymer. From thermal denaturation studies and circular dichroism spectroscopy, we found that the extent of drug sequestration depends on the binding affinity of EPR to the duplex DNA, and this mixed micellar system can be employed for the removal of excess drug in the case of a drug overdose.

Thermal Reversibility and Structural Stability in Lysozyme Induced by Epirubicin Hydrochloride

Herein we report the binding interactions between lysozyme (Lyz) and an anthracycline drug, epirubicin hydrochloride (EPR), through an extensive spectroscopic approach at both ensemble average and single molecular resolution. Our steady-state and time-resolved fluorescence spectroscopy reveals that the drug-induced fluorescence quenching of the protein proceeds through a static quenching mechanism. Isothermal titration calorimetry (ITC) and steady-state experiments reveal almost similar thermodynamic signatures of the drug-protein interactions. The underlying force that plays pivotal roles in the said interaction is hydrophobic in nature, which is enhanced in the presence of a strong electrolyte (NaCl). Circular dichroism (CD) spectra indicate that there is a marginal increase in the secondary structure of the native protein (α-helical content increases from 26.9 to 31.4% in the presence of 100 μM EPR) upon binding with the drug. Fluorescence correlation spectroscopy (FCS) was used to monitor the changes in structure and conformational dynamics of Lyz upon interaction with EPR. The individual association (K_ass = 0.33 × 10⁶ ms^-1 M^-1) and dissociation (K_diss = 1.79 ms^-1) rate constants and the binding constant (K_b = 1.84 × 10⁵ M^-1) values, obtained from fluctuations of fluorescence intensity of the EPR-bound protein, have also been estimated. AutoDock results demonstrate that the drug molecule is encapsulated within the hydrophobic pocket of the protein (in close proximity to both Trp62 and Trp108) and resides ∼20 Å apart from the covalently labelled CPM dye. Förster resonance energy transfer (FRET) studies proved that the distance between the donor (CPM) and the acceptor (EPR) is ∼22 Å, which is very similar to that obtained from molecular docking analysis (∼20 Å). The system also shows temperature-dependent reversible FRET, which may be used as a thermal sensor for the temperature-sensitive biological systems.

A Value of Information Analysis of Research on the 21-Gene Assay for Breast Cancer Management

OBJECTIVES

The 21-gene assay Oncotype DX (21-GA) shows promise as a guide in deciding when to initiate adjuvant chemotherapy in women with hormone receptor-positive early-stage breast cancer. Nevertheless, its routine use remains controversial, owing to insufficient evidence of its clinical utility and cost-effectiveness. Accordingly, we aim to quantify the value of conducting further research to reduce decision uncertainty in the use of the 21-GA.

METHODS

Using value of information methods, we first generated probability distributions of survival and costs for decision making with and without the 21-GA alongside traditional risk prediction. These served as the input to a comparison of 3 alternative study designs: a retrospective observational study to update risk classification from the 21-GA, a prospective observational study to estimate prevalence of chemotherapy use, and a randomized controlled trial (RCT) of the 21-GA predictive value.

RESULTS

We found that current evidence strongly supports the use of the 21-GA in intermediate- and high-risk women. Further research should focus on low-risk women, among whom the cost-effectiveness findings remained equivocal. For this population, we identified a high value of reducing uncertainty in the 21-GA use for all proposed research studies. The RCT had the greatest potential to efficiently reduce the likelihood of choosing a suboptimal strategy, providing a value between $162 million and $1.1 billion at willingness-to-pay thresholds of $150 000 to $200 000/quality-adjusted life years.

CONCLUSION

Future research to inform 21-GA decision making is of high value. The RCT of the 21-GA predictive value has the greatest potential to efficiently reduce decision uncertainty around 21-GA use in women with low-risk early-stage breast cancer.

Focus on an infrequently used quantity in the context of competing risks: The conditional probability function

In clinical studies of hematologic and oncologic diseases, the outcomes of interest are generally composite time to event endpoints which are usually defined by occurrence of different event types. Nonetheless, clinicians are interested in studying only one event type, which leads to a competing risks situation. In this context, Pepe and Mori presented a quantity directly derived from the cumulative incidence: the conditional probability. This function defines the probability that a given event occurs, conditionally on not having had a competing event by that time. The objective of this paper is to present this conditional cumulative incidence function and to compare its use to the cumulative incidence in different data sets. Different scenarios highlight the importance of the competing event on the interpretation of the conditional probability. Conditional probability needs to be interpreted jointly with the cumulative incidence. This quantity can be of interest especially when the risk of the competing event is large, strongly precludes the risk of the event of interest and provides useful additional information.

Cost-Effectiveness Analyses of the 21-Gene Assay in Breast Cancer: Systematic Review and Critical Appraisal

Purpose Prior studies examining cost effectiveness of the 21-gene assay (Oncotype DX [ODX]) for women with hormone receptor-positive, early-stage breast cancer have yielded disparate results. We aimed to explore why these analyses may have yielded different conclusions. Methods We conducted a systematic literature review of cost-effectiveness analyses (CEAs) of ODX. We examined the extent to which the structure of CEA modeling, the assumptions of the models, and the selection of input parameters influenced cost-effectiveness estimates. We also explored the prevalence of industry funding and whether industry funding was associated with study designs favoring ODX. Results We identified 27 analyses, 15 of which received industry funding. In 18 studies, the clinical characteristics (eg, tumor size and grade) commonly used to make chemotherapy decisions were not incorporated into simulation modeling; thus, these studies would favor ODX being cost effective and might not reflect clinical practice. Most studies ignored the heterogeneous effect of ODX on chemotherapy use; only five studies assumed that ODX would increase chemotherapy use for clinically low-risk patients but decrease chemotherapy use for clinically high-risk patients. No study used population-based joint distributions of ODX recurrence score and tumor characteristics, and 12 studies inappropriately assumed that chemotherapy would increase distant recurrence for the low recurrence score group; both approaches overestimated the benefits of ODX. Industry-funded studies tended to favor ODX; all five studies that reported ODX as being cost saving were industry funded. In contrast, two studies that reported an incremental cost-effectiveness ratio > $50,000 per quality-adjusted life-year were not funded by industry. Conclusion Although a majority of published analyses indicated that ODX is cost effective, they incorporated study designs that can increase the risk of bias.

Are health care providers who work with cancer drugs at an increased risk for toxic events? A systematic review and meta-analysis of the literature

Objective. A systematic review and meta-analysis was conducted to test the hypothesis that oncology health care workers are at an increased risk of cancer, reproductive complications and acute toxic events.

Design. A structured literature search of Index Medicus/MEDLINE, CINAHL, EMBASE, the Cochrane Database of Systematic Reviews and Healthstar was performed from 1966 to December 2004 for human epidemiological studies evaluating the risk of toxic events in health care workers exposed to cytotoxic drugs. Raw data and adjusted odds ratios (OR) reported in eligible studies were combined using a random effects model to calculate point estimates and 95% confidence intervals (CI) for each potential risk outcome.

Main outcome measures. Adjusted OR for congenital malformations, stillbirths and spontaneous abortions among health care workers exposure to cytotoxic agents compared to a non-exposed control group.

Results. The systematic review identified 14 studies evaluating the outcomes of interest, seven of which were suitable for statistical pooling. Due to lack of evidence, we were unable to estimate a pooled OR for the risk of cancer and acute toxic events. However, no significant association was detected between exposure to cytotoxic drugs and; congenital malformations (OR=1.64; 95% CI: 0.91-2.94) and stillbirths (OR=1.16; 95% CI: 0.73-1.82). In contrast, an association was identified between exposure to chemotherapy and spontaneous abortions (OR=1.46; 95% CI: 1.11-1.92).

Conclusions. The results of this systematic review identified a small incremental risk for spontaneous abortions in female staff working with cytotoxic agents. Health policy decision makers should effectively communicate the magnitude of this risk to their staff and implement cost effective interventions for its reduction or elimination.

Effects of diallyl trisulfide on induction of apoptotic death in murine leukemia WEHI-3 cells in vitro and alterations of the immune responses in normal and leukemic mice in vivo

Diallyl trisulfide (DATS), a chemopreventive dietary constituent and extracted from garlic, has been shown to against cultured many types of human cancer cell liens but the fate of apoptosis in murine leukemia cells in vitro and immune responses in leukemic mice remain elusive. Herein, we clarified the actions of DATS on growth inhibition of murine leukemia WEHI-3 cells in vitro and used WEHI-3 cells to generate leukemic mice in vivo, following to investigate the effects of DATS in animal model. In in vitro study, DATS induced apoptosis of WEHI-3 cells through the G0/G1 phase arrest and induction of caspase-3 activation. In in vivo study DATS decreased the weight of spleen of leukemia mice but did not affect the spleen weight of normal mice. DATS promoted the immune responses such as promotions of the macrophage phagocytosis and NK cell activities in WEHI-3 leukemic and normal mice. However, DATS only promotes NK cell activities in normal mice. DATS increases the surface markers of CD11b and Mac-3 in leukemia mice but only promoted CD3 in normal mice. In conclusion, the present study indicates that DATS induces cell death through induction of apoptosis in mice leukemia WHEI-3 cells. DATS also promotes immune responses in leukemia and normal mice in vivo.

Age related risk of myelodysplastic syndrome and acute myeloid leukemia among breast cancer survivors

Increased incidence of acute myeloid leukemia (AML) has been identified among breast cancer (BC) survivors but measurement has not included myelodysplastic syndrome (MDS). Our aim is to identify age and stage related MDS/AML incidence post BC diagnosis. We used the 2001-2009 Surveillance, Epidemiology, and end results (SEER) database to identify first primary stage I-III BC patients. Subsequent MDS or AML diagnosis was identified with observed rates compared to expected MDS/AML incidence in the general population. Age adjusted observed/expected rate ratios and 95 % confidence intervals (CI) were calculated. The unadjusted all age and stage MDS/AML incidence rate was .15 % (470/306,691) with a progressively higher rate by age (age 20-49 = .11, age 50-64 = .14, age 65+ =.21, and age 75+ =.18) and stage (stage I = .11, stage II = .18, and stage III = .22). Compared to the general population, BC patients had a 2.75-fold [95 % CI 2.51-3.00] increased relative risk of being diagnosed with MDS/AML. Young age survivors had highest relative risk [age 20-49: relative risk (RR) = 10.60 (95 % CI 8.57-12.93); age 50-64: 5.96 (95 % CI 5.13, 6.88); age 65-74 year-olds: 2.94 (95 % CI 2.45, 3.50); and age ≥75 year-olds: 1.28 (95 % CI 1.03, 1.56)]. Separately MDS relative risk was highest among young women [30.44 (95 % CI = 19.63, 44.62)]. MDS/AML relative risk increased from 1.87 to 5.66 for stage I-III.

CONCLUSIONS

Myelodysplastic syndrome and acute myeloid leukemia relative risk is substantially elevated among breast cancer survivors especially those aged 20-49. While the actual number is small, MDS/AML is a serious disease. More research is needed to identify the treatments that put women at risk and find less leukemogenic options, especially for young women.

t(8;16) AML developed subsequent to breast cancer therapy

We report a breast cancer patient who developed acute myeloid leukemia (AML) one year following her adjuvant chemotherapy consisting of cyclophosphamide, adriamycin and 5-fluorouracil. Cytogenetic examination of bone marrow samples resulted in t(8;16)(p11.2;p13.3), which is a chromosome rearrangement observed in de novo and treatment related AML M4/M5 with a poor prognosis.

Herbal medicine and acupuncture for breast cancer palliative care and adjuvant therapy

Breast cancer is a life-threatening disease among women worldwide with annual rates of reported incidence and death increasing alarmingly. Chemotherapy is a recommended and effective treatment option for breast cancer; however, the narrow therapeutic indices and varied side effects of currently approved drugs present major hurdles in increasing its effectiveness. An increasing number of literature evidence indicate that complementary and alternative medicine (CAM) used in treatment-related symptom control and alleviation of side effects plays an important role in increasing survival rate and quality of life in breast cancer patients. This review focuses on the use of herbal medicines and acupuncture in palliative care and as adjuvants in the treatment of breast cancer. Herbal medicinal treatments, the correlation of clinical use with demonstrated in vitro and in vivo mechanisms of action, and the use of certain acupoints in acupuncture are summarized. The aim of this review is to facilitate an understanding of the current practice and usefulness of herbal medicine and acupuncture as adjuvants in breast cancer therapy.

Adjuvant docetaxel, doxorubicin, and cyclophosphamide in node-positive breast cancer: 10-year follow-up of the phase 3 randomised BCIRG 001 trial

BACKGROUND

We compared standard adjuvant anthracycline chemotherapy with anthracycline-taxane combination chemotherapy in women with operable node-positive breast cancer. Here we report the final, 10-year follow-up analysis of disease-free survival, overall survival, and long-term safety.

METHODS

BCIRG 001 was an open label, phase 3, multicentre trial in which 1491 patients aged 18-70 years with node-positive, early breast cancer and a Karnofsky score of 80% or more were randomly assigned to adjuvant treatment with docetaxel, doxorubicin, and cyclophosphamide (TAC) or fluorouracil, doxorubicin, and cyclophosphamide (FAC) every 3 weeks for six cycles. Randomisation was stratified according to institution and number of involved axillary lymph nodes per patient (one to three vs four or more). Disease-free survival was the primary endpoint and was defined as the interval between randomisation and breast cancer relapse, second primary cancer, or death, whichever occurred first. Efficacy analyses were based on the intention-to-treat principle. BCIRG 001 is registered with ClinicalTrials.gov, number NCT00688740.

FINDINGS

Enrolement took place between June 11, 1997 and June 3, 1999; 745 patients were assigned to receive TAC and 746 patients were assigned to receive FAC. After a median follow-up of 124 months (IQR 90-126), disease-free survival was 62% (95% CI 58-65) for patients in the TAC group and 55% (51-59) for patients in the FAC group (hazard ratio [HR] 0·80, 95% CI 0·68-0·93; log-rank p=0·0043). 10-year overall survival was 76% (95% CI 72-79) for patients in the TAC group and 69% (65-72) for patients in the FAC group (HR 0·74, 0·61-0·90; log-rank p=0·0020). TAC improved disease-free survival relative to FAC irrespective of nodal, hormone receptor, and HER2 status, although not all differences were significant in these subgroup analyses. Grade 3-4 heart failure occurred in 26 (3%) patients in the TAC group and 17 (2%) patients in the FAC group, and caused death in two patients in the TAC group and four patients in the FAC group. A substantial decrease in left ventricular ejection fraction (defined as a relative decrease from baseline of 20% or more) was seen in 58 (17%) patients who received TAC and 41 (15%) patients who received FAC. Six patients who received TAC developed leukaemia or myelodysplasia, as did three patients who received FAC.

INTERPRETATION

Our results provide evidence that the initial therapeutic outcomes seen at the 5-year follow-up with a docetaxel-containing adjuvant regimen are maintained at 10 years. However, a substantial percentage of patients had a decrease in left ventricular ejection fraction, probably caused by anthracycline therapy, which warrants further investigation.

FUNDING

Sanofi.

Acute myeloid leukemia of donor origin after allogeneic stem cell transplantation from a sibling who harbors germline XPD and XRCC3 homozygous polymorphisms

A 54-year-old woman was diagnosed with infiltrative ductal breast carcinoma. Two years after treatment, the patient developed an acute myeloid leukemia (AML) which harbored del(11q23) in 8% of the blast cells. The patient was submitted for allogeneic stem cell transplantation (aSCT) from her HLA-compatible sister. Ten months after transplantation, she relapsed with an AML with basophilic maturation characterized by CD45^low CD33^high, CD117⁺, CD13^-/+, HLA Dr^high, CD123^high, and CD203c⁺ blast cells lacking expression of CD7, CD10, CD34, CD15, CD14, CD56, CD36, CD64, and cytoplasmic tryptase. Karyotype analysis showed the emergence of a new clone with t(2;14) and FISH analysis indicated the presence of MLL gene rearrangement consistent with del(11q23). Interestingly, AML blast cell DNA tested with microsatellite markers showed the same pattern as the donor's, suggesting that this AML emerged from donor cells. Additionally, polymorphisms of the XPA, XPD, XRCC1, XRCC3 and RAD51 DNA repair genes revealed three unfavorable alleles with low DNA repair capacity.

In summary, we report the first case of AML involving XPD and XRCC3 polymorphisms from donor origin following allogeneic stem cell transplantation and highlight the potential need for careful analysis of DNA repair gene polymorphisms in selecting candidate donors prior to allogeneic stem cell transplantation.

Safe handling of parenteral cytotoxics: recommendations for ontario

In caring for patients with cancer, health care workers may be exposed to cytotoxic agents. Recommendations are needed to mitigate potential risks for cancer and adverse reproductive outcomes associated with exposure.

Risk of second cancer after initial treatment of breast cancer: An Osaka Cancer Registry Database study

In the present study, the association between the incidence of second cancer and initial treatment for primary breast cancer was investigated using the Osaka Cancer Registry in Japan. We selected 45,575 patients diagnosed with breast cancer between January 1975 and December 2003. Information on initial cancer treatment and second cancer was obtained from the Osaka Cancer Registry. Patients were classified according to initial treatment (chemo-, hormone, or radiotherapy, or no treatment). We calculated the incidence rate ratio of second cancers in patients classified by treatment for the first cancer. The effects of treatment adjusted for covariates on second cancers were examined using stratified analyses and a Cox proportional hazard model. The final number of 33,043 subjects had a mean duration of follow-up of 5.2±4.3 years, during which 1,857 second cancers were diagnosed. For hormone therapy, the incidence rate ratio (IRR) of all second cancers was 0.64 [95% confidence interval (CI), 0.58-0.70], and that of corpus uteri cancer was 3.04 (95% CI, 1.78-5.19). The multivariate analysis revealed that the IRR of corpus uteri cancer associated with hormone therapy was 2.53 (95% CI, 1.41‑4.55). The incidence rate of all second cancers associated with initial treatment was lower than that associated with no treatment. Only second corpus uteri cancer may be related to hormone therapy.

Increased incidence of myelodysplastic syndrome and acute myeloid leukemia following breast cancer treatment with radiation alone or combined with chemotherapy: a registry cohort analysis 1990-2005

Background

Our objective was to measure myelodysplastic syndrome (MDS) and acute myelogenous leukemia (AML) risk associated with radiation and/or chemotherapy breast cancer (BC) treatment.

Methods

Our study cohort was composed of BC patients diagnosed from 1990 to 2005 and followed up for blood disorders, mean length of follow up = 7.17 years, range 2-18 years. 5790 TNM stage 0-III patients treated with surgery alone, radiation and/or chemotherapy were included. Patients without surgery (n = 111), with stem cell transplantation (n = 98), unknown or non-standard chemotherapy regimens (n = 94), lost to follow up (n = 66) or 'cancer status unknown' (n = 67) were excluded. Rates observed at our community based cancer care institution were compared to SEER incidence data for rate ratio (RR) calculations.

Results

17 cases of MDS/AML (10 MDS/7 AML) occurred during the follow up period, crude rate .29% (95% CI = .17, .47), SEER comparison RR = 3.94 (95% CI = 2.34, 6.15). The RR of MDS in patients age < 65 comparing our cohort incidence to SEER incidence data was 10.88 (95% CI = 3.84, 24.03) and the RR of AML in patients age < 65 was 5.32 (95% CI = 1.31, 14.04). No significant increased risk of MDS or AML was observed in women ≥ 65 or the surgery/chemotherapy-only group. A RR of 3.32 (95% CI = 1.42, 6.45) was observed in the surgery/radiation-only group and a RR of 6.32 (95% CI = 3.03, 11.45) in the surgery/radiation/chemotherapy group. 3 out of 10 MDS cases died of disease at an average 3.8 months post diagnosis and five of seven AML cases died at an average 9 months post diagnosis.

Conclusions

An elevated rate of MDS and AML was observed among breast cancer patients < 65, those treated with radiation and those treated with radiation and chemotherapy compared to available population incidence data. Although a small number of patients are affected, leukemia risk associated with treatment and younger age is significant.

TP53 genomics predict higher clinical and pathologic tumor response in operable early-stage breast cancer treated with docetaxel-capecitabine ± trastuzumab

To determine rates of pathologic complete response (pCR) and near-complete response (npCR) in operable early-stage breast cancer using neoadjuvant capecitabine plus docetaxel, with or without trastuzumab, and investigate biomarkers of pathologic response. Women with operable early-stage breast cancer were enrolled in a multicenter study of neoadjuvant therapy for four 21-day cycles with capecitabine 825 mg/m(2) plus docetaxel 75 mg/m(2) if human epidermal growth factor receptor 2 (HER2)-negative, and additionally, a standard trastuzumab dose if HER2-positive. Primary endpoint was rate of pCR and npCR. Secondary endpoints were potential associations between response and TP53 mutational analysis using the AmpliChip TP53 assay or immunohistochemical (IHC) staining, and genomic subtyping using the PAM50 assay. In patients who completed treatment and surgery, pCR and npCR rates were 15.8% in patients with HER2-negative and 50% in patients with HER2-positive tumors. Stratified by genomic subtype, patients of HER2-enriched subtype had the best response (72.2%), and luminal A (9.1%) and B (4.8%) subtypes, the poorest. Of 147 patients tested for TP53 mutations using the AmpliChip assay, 78 variants were detected; 55 were missense. Response rate among TP53-mutated patients was 30%, significantly higher than TP53 wild-type patients (10%; P = 0.0032). Concordance between AmpliChip mutation status versus TP53 IHC staining was 65%, with AmpliChip status predictive of response and IHC status not predictive. Capecitabine plus docetaxel in HER2-negative, and with trastuzumab in HER2-positive patients, provided a good response rate with four cycles of non-anthracycline-containing therapy. TP53 mutational analysis and genomic subtyping were predictive.

Use of white blood cell growth factors and risk of acute myeloid leukemia or myelodysplastic syndrome among elderly patients with non-Hodgkin lymphoma

BACKGROUND

The current study was conducted to evaluate the association between colony-stimulating factor (CSF) use and the risk of developing therapy-related myelodysplastic syndromes or acute myeloid leukemia (t-MDS/AML) among a large cohort of elderly patients with non-Hodgkin lymphoma (NHL) who were treated with chemotherapy.

METHODS

A total of 13,203 NHL patients were identified from the Surveillance, Epidemiology, and End Results-Medicare database who were diagnosed from 1992 through 2002. Patients were followed from their initial chemotherapy date until the date they were diagnosed with t-MDS/AML, death, or last follow-up (October 31, 2006), whichever occurred first.

RESULTS

Overall, 40% (n = 5266) of patients received CSF. During the follow-up period (median follow-up, 2.9 years [range, 1-14.7 years]), 272 (5.2%) patients who were treated with CSF developed t-MDS/AML, compared with 230 (2.9%) patients who did not (P < .0001, log-rank test). The 5-year incidence of t-MDS/AML for patients receiving CSF was 14.1 per 1000 person-years compared with 8.3 per 1000 person-years for patients not receiving CSF. In a multivariable Cox regression analysis adjusted for gender, histology, stage, comorbidities, radiotherapy, and chemotherapy agent, CSF use was found to be independently associated with a 53% increased risk of t-MDS/AML (hazard ratio [HR], 1.53; 95% confidence interval [95% CI], 1.26-1.84). The observed association between CSF use and t-MDS/AML persisted across histologic subgroups (ie, diffuse large B-cell lymphoma, follicular lymphoma, and others). Patients who received both CSF and antimetabolite chemotherapy were found to have a 2.5-fold increased risk of t-MDS/AML (HR, 2.49; 95% CI, 1.91-3.26) compared with patients who received neither agent.

CONCLUSIONS

The current study, which to our knowledge is the first large population-based study published to date, demonstrated that the administration of CSF among elderly NHL patients receiving chemotherapy was associated with an increased risk of t-MDS/AML, although the absolute risk was low.

Optimizing chemotherapy regimens for patients with early-stage breast cancer

While moving toward a personalized treatment approach for early breast cancer, it is clear that treatment must be tailored specifically to the tumor's and patient's characteristics. Understanding the tumor's molecular signature and using validated prognostic and predictive tools can assist the oncologist in providing the optimal therapy. Through a shared decision process, a treatment plan must be formulated based on the tumor's biologic phenotype, taking into consideration the patient's comorbidities and preferences. This review summarizes the available tools that can assist in this process and provides an overview of the chemotherapy regimens approved for the adjuvant treatment of patients with early-stage breast cancer.

Acute myeloid leukemia or myelodysplastic syndrome in randomized controlled clinical trials of cancer chemotherapy with granulocyte colony-stimulating factor: a systematic review

PURPOSE

To evaluate the risk of acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS) and overall mortality in patients receiving chemotherapy with or without granulocyte colony-stimulating factor (G-CSF), a systematic review of randomized controlled trials (RCTs) was conducted.

METHODS

Electronic databases searched through October 2008 identified 3,794 articles for initial screening. Eligibility included solid tumor or lymphoma patients randomly assigned to chemotherapy with or without G-CSF support, > or = 2 years of follow-up, and reporting AML/MDS or all second malignancies. Dual blinded data extraction was performed. Relative risk (RR) and absolute risk (AR) estimates +/- 95% CIs were calculated by the Mantel-Haenszel method.

RESULTS

In the 25 eligible RCTs, 6,058 and 6,746 patients were randomly assigned to receive chemotherapy with and without initial G-CSF support, respectively. At mean and median follow-up across studies of 60 and 53 months, respectively, AML/MDS was reported in 22 control patients and 43 G-CSF-treated patients, with an estimated RR of 1.92 (95% CI, 1.19 to 3.07; P = .007) and AR increase of 0.41% (95% CI, 0.10% to 0.72%; P = .009). Deaths were reported in 1,845 patients randomly assigned to G-CSF and in 2,099 controls, for estimates of RR and AR decrease of 0.897 (95% CI, 0.857 to 0.938; P < .001) and 3.40% (95% CI, 2.01% to 4.80%; P < .001), respectively. Greater RR reduction for mortality was seen for both larger studies (P = .05) and greater chemotherapy dose-intensity (P = .012).

CONCLUSION

Delivered chemotherapy dose-intensity and risk of AML/MDS are increased but all-cause mortality is decreased in patients receiving chemotherapy with G-CSF support. Greater reductions in mortality were observed with greater chemotherapy dose-intensity.

Screening for clonal hematopoiesis as a predictive marker for development of therapy-related myeloid neoplasia (t-MN) following neoadjuvant therapy for breast cancer: a Southwest Oncology Group study (S0012)

A serious complication associated with breast cancer treatment is the increased risk for development of therapy-related myeloid neoplasms (t-MN). To determine whether dose-intensive adjuvant regimens for breast cancer induce genetic damage to hematopoietic stem cells, defined by the emergence of clonal hematopoiesis, and whether detection of clonal hematopoiesis could be used as an early marker for the subsequent development of t-MN, the Southwest Oncology Group designed a pilot clonality investigation to estimate the incidence of clonal hematopoiesis during and shortly after completion of the dose intensive neoadjuvant regimens for high-risk breast cancer patients. Peripheral blood samples from 274 patients obtained prior to treatment, at time of surgery, and at 6 and 12 months post-surgery were examined by two different clonality assays: the HUMARA (HUMan Androgen Receptor) assay to estimate the incidence of early genetic damage by clonal proliferation, and microsatellite instability (MSI) testing to screen for LOH or defective DNA mismatch repair mechanisms. Clonal hematopoiesis was negative in 93.5% of the samples analyzed. Five patients showed a HUMARA-positive/MSI-negative pattern, and no patients showed a HUMARA-negative/MSI-positive pattern. With a median follow-up of 3.1 years, one patient in our study developed t-AML at 3 years 5 months after randomization. Our results indicate that clonal hematopoiesis assays performed within the 2 years following dose-intensive neoadjuvant therapy failed to identify an emerging clonal hematopoietic stem cell population. Longer clinical follow-up will be necessary to define better the positive predictive value of detecting clonal hematopoiesis in the HUMARA+/MSI- cases.

Commentary: anthracyclines in early-stage breast cancer: is it the end of an era?

The author argues for the view that the clinical role of the anthracyclines will persist in the adjuvant therapy of breast cancer for some time to come.

Cyclin E correlates with manganese superoxide dismutase expression and predicts survival in early breast cancer patients receiving adjuvant epirubicin-based chemotherapy

Anthracycline-based chemotherapy represents a milestone in the treatment of breast cancer. We previously demonstrated in an in vitro model that cyclin E overexpression is associated with increased expression of manganese superoxide dismutase (MnSOD) and resistance to doxorubicin. In the present study, immunohistochemical expression of cyclin E and MnSOD was evaluated in 134 early breast cancer patients receiving adjuvant epirubicin-based chemotherapy regimens containing epirubicin. Both parameters were correlated with the available clinicopathological parameters and with the outcome of patients. Overexpression of cyclin E and MnSOD was detected in 46 (34.3%) and 56 (41.8%) patients, respectively, and expression levels of the two proteins were related. Disease-free and alive patients displayed a lower mean percentage of cyclin E-expressing cells than relapsed and dead patients, respectively. Kaplan-Meier survival analysis demonstrated a significant separation between high versus low cyclin E-expressing tumors in terms of overall survival (P = 0.038 by log-rank). Similar results were obtained considering the subset of node-negative patients separately. No significant relationship with patient outcome was observed for MnSOD expression levels. At multivariate analysis cyclin E failed to demonstrate an independent prognostic value. In conclusion, the results of the present study support previous evidence that increased cyclin E expression is associated with higher MnSOD expression levels and poorer outcome, at least as evaluated in terms of overall survival. Further studies are warranted to evaluate the usefulness of cyclin E as a prognostic marker to identify breast cancer patients at higher risk of death from the disease when treated with adjuvant anthracycline-based therapy.

Long-term benefit of high-dose epirubicin in adjuvant chemotherapy for node-positive breast cancer: 15-year efficacy results of the Belgian multicentre study

PURPOSE

The 4-year results of this trial demonstrated that a higher dose of epirubicin with cyclophosphamide (HEC) is superior to a lower dose of epirubicin, 60 mg/m(2) (EC), for event-free survival (EFS; 27% reduction), but is not superior to classical oral cyclophosphamide, methotrexate, and fluorouracil (CMF) in the adjuvant treatment of node-positive breast cancer. Herein we report the 15-year data on efficacy and long-term toxicity of this three-arm Belgian multicenter trial.

PATIENTS AND METHODS

Between March 1988 and December 1996, 777 eligible patients were randomly assigned to six cycles of CMF, eight cycles of EC, or eight cycles HEC.

RESULTS

The 15-year EFS was 45% for patients who received CMF, 39% for patients who received EC, and 50% for patients who received HEC. The hazard ratios (HR) were 0.77 for HEC versus EC (95% CI, 0.60 to 0.98; P = .03), 0.90 for HEC versus CMF (P = .39), and 0.86 for EC versus CMF (P = .21). No difference in overall survival (OS) was seen. Cardiac toxicity was more frequent with HEC than with CMF (11 patients v 1 patient; P = .006), but no more than with EC (P = .21).

CONCLUSION

Treatment with HEC demonstrated superior EFS when compared with lower-dose epirubicin. However, we do not recommend the use of HEC regimen in daily clinical practice, mainly because of the higher risk of cardiotoxicity related to the cumulative doses of epirubicin and the lack of superiority of anthracyclines over CMF in our study.

Simultaneous determination of cyclophosphamide, ifosfamide, doxorubicin, epirubicin and daunorubicin in human urine using high-performance liquid chromatography/electrospray ionization tandem mass spectrometry: bioanalytical method validation

A reversed-phase high-performance liquid chromatography (rp-HPLC) system interfaced with an electrospray ionization (ESI) source coupled to tandem mass spectrometry (MS/MS) was developed and validated for the determination of cyclophosphamide (CP), ifosfamide (IF), daunorubicin (DNR), doxorubicin (DXR), and epirubicin (EPI) in human urine. The analysis of samples containing multiple analytes with a dissimilar range of polarities was carried out using a conventional reversed-phase chromatographic BDS Hypersil C8 column. The analytical run was 15 min. The triple quadrupole mass spectrometer was operated in positive ion mode and multiple reaction monitoring (MRM) was used for drug quantification. The method was validated over a concentration range of 0.2 to 4.0 microg.L(-1) for CP, IF, DXR, EPI and 0.15-2.0 microg.L(-1) for DNR in human urine. The lower limit of quantification (LLOQ) was 0.2 microg.L(-1) for CP, IF, EPI and was set at 0.3 and 0.15 microg.L(-1) for DXR and DNR, respectively. The relative standard deviations (RSD%) were <11.2% for inter- and intra-day precisions. The overall accuracy was also within 114.7% for all analytes at the concentrations of the quality control samples. The potential of ionization suppression resulting from the endogenous biological material on the rp-HPLC/MS/MS method was evaluated and measured. The feasibility of the proposed HPLC/ESI-MS/MS procedure was demonstrated by analyzing urine samples from pharmacy technicians and nurses working in hospitals or personnel employed in drug-manufacturing plants.

Acute myeloid leukemia after breast cancer: a population-based comparison with hematological malignancies and other cancers

BACKGROUND

Clinical trials frequently report acute myeloid leukemia (AML) as a complication of adjuvant chemotherapy for breast cancer (BC).

PATIENTS AND METHODS

This retrospective population-based study investigated AML risk after a prior BC diagnosis and compared the results with women after a prior diagnosis of hematological malignancies (HM), other cancers combined (OCC), and the age-matched Australian female population.

RESULTS

Women with a prior BC diagnosis had 2.56 times the risk of developing AML compared with the Australian female population (P<0.001). AML risk was also elevated after prior HM and OCC diagnoses (4.73, P<0.001, and 1.70, P<0.001, respectively). Although the incidence of AML rose sharply with age in all cohorts, the age-specific relative risk was highest in the 30- to 49-age-group and decreased with increasing age. AML risk increased with the duration of follow-up but there was no change of risk during the 23 years of this study.

CONCLUSION

AML risk was elevated after a prior diagnosis of BC but there was no evidence of an increasing risk of AML after a BC diagnosis or, in any of the other cancer cohorts, during this era of expansion of the evidence base for more intensive treatments.

A MLL-KIAA0284 fusion gene in a patient with secondary acute myeloid leukemia and t(11;14)(q23;q32)

MLL aberrations are found in approximately 10% of acute leukemias. More than 80 different MLL fusion genes have been cytogenetically described but a significant number of MLL fusion partners remain unidentified on the molecular level. We describe here the case of a patient who developed secondary acute myeloid leukemia five years after the patient had received adjuvant radiochemotherapy because of breast cancer. This therapy comprised 4 cycles epirubicin/cyclophosphamide, a mitoxantrone-based high-dose chemotherapy with autologous stem cell transplantation and a subsequent radiation. Cytogenetic bone marrow analysis revealed a translocation t(11;14)(q23;q32), with a MLL split signal in FISH analysis. By applying a long-distance inverse PCR method the KIAA0284 gene was identified as translocation partner. Both breakpoints, on chromosomes 11 and 14, were characterized. The breakpoint in the KIAA0284 gene was located 5' of the putative start codon and an in-frame MLL-KIAA0284 transcript was detectable by RT-PCR. The KIAA0284 gene has hitherto not been implicated in hematologic diseases and has never been reported as a translocation partner. Its physiological function is unknown. The expression of KIAA0284 in various tissues and hematologic diseases was investigated by real time quantitative PCR and turned out to be very low in all lymphatic and myeloid diseases investigated.

Outcome of patients who develop acute leukemia or myelodysplasia as a second malignancy after solid tumors treated surgically or with strategies that include chemotherapy and/or radiation

BACKGROUND

Evaluation of therapeutic outcomes and risk factors was undertaken for patients with primary solid tumors (PST) developing acute leukemia or myelodysplasia (MDS) as a second malignancy.

METHODS

In all, 131 consecutive patients presenting to a single institution with leukemia or MDS after treatment for PST with surgery or chemotherapy/radiotherapy were examined. Management of the secondary acute leukemia and MDS consisted either of intensive therapy including allogeneic blood and marrow transplants or supportive measures.

RESULTS

The time from diagnosis of PST to development of acute leukemia or MDS, the cytogenetic profile of patients, and their survival were similar irrespective of PST therapy with surgery alone or strategies involving chemotherapy and/or radiation. The median survival of all 131 patients was 10.5 months with a 5-year survival of 15.6%. Induction therapy and/or transplantation resulted in a median survival of 13.6 months and a 5-year survival of 26.6% compared with 6.5 months and 2% with supportive measures. Subset analysis of transplant recipients revealed a median survival of 17.6 months and a 37.9% 5-year survival. Despite a significantly lower recurrence rate the survival of transplant recipients was not improved secondary to a higher treatment-related mortality (TRM) rate.

CONCLUSIONS

Patients developing acute leukemia or MDS after PST demonstrated similar cytogenetic profiles and clinical outcomes independent of the type of treatment. Survival was significantly better for patients able to undergo intensive therapy compared with supportive measures. The low recurrence rate for allograft recipients was consistent with a potent antileukemic effect that may translate into a survival benefit if TRM could be reduced.

Canadian supportive care recommendations for the management of neutropenia in patients with cancer

Hematologic toxicities of cancer chemotherapy are common and often limit the ability to provide treatment in a timely and dose-intensive manner. These limitations may be of utmost importance in the adjuvant and curative intent settings. Hematologic toxicities may result in febrile neutropenia, infections, fatigue, and bleeding, all of which may lead to additional complications and prolonged hospitalization. The older cancer patient and patients with significant comorbidities may be at highest risk of neutropenic complications. Colony-stimulating factors (csfs) such as filgrastim and pegfilgrastim can effectively attenuate most of the neutropenic consequences of chemotherapy, improve the ability to continue chemotherapy on the planned schedule, and minimize the risk of febrile neutropenia and infectious morbidity and mortality. The present consensus statement reviews the use of csfs in the management of neutropenia in patients with cancer and sets out specific recommendations based on published international guidelines tailored to the specifics of the Canadian practice landscape. We review existing international guidelines, the indications for primary and secondary prophylaxis, the importance of maintaining dose intensity, and the use of csfs in leukemia, stem-cell transplantation, and radiotherapy. Specific disease-related recommendations are provided related to breast cancer, non-Hodgkin lymphoma, lung cancer, and gastrointestinal cancer. Finally, csf dosing and schedules, duration of therapy, and associated acute and potential chronic toxicities are examined.

Postoperative dose-dense sequential chemotherapy with epirubicin, paclitaxel and CMF in patients with high-risk breast cancer: safety analysis of the Hellenic Cooperative Oncology Group randomized phase III trial HE 10/00

BACKGROUND

A randomized phase III trial in high-risk breast cancer patients was conducted, to further explore the impact of dose-density in the adjuvant treatment for breast cancer. The safety analysis is presented.

PATIENTS AND METHODS

From October 2000 until June 2005, 1121 node-positive patients were randomized to sequential dose-dense epirubicin 110 mg/m(2) and paclitaxel (Taxol, Bristol Myers-Squibb, Princeton, New Jersey, USA) 250 mg/m(2) (group A), or concurrent epirubicin 83 mg/m(2) and paclitaxel 187 mg/m(2) (group B), both followed by three cycles of 'intensified' combination chemotherapy with cyclophosphamide, methotrexate and fluorouracil (CMF). Granulocyte colony-stimulating factor was given prophylactically with the dose-dense treatments.

RESULTS

Median dose intensity of epirubicin and paclitaxel was double in group A, as designed, with significantly less cycles administered at full dose (P < 0.001). Median cumulative dose of all drugs and total treatment duration, however, were identical between groups. Severe taxane-related toxic effects were more frequent in group A, while severe thrombocytopenia was low and present only in group A. There were no differences in the rates of other hematological toxic effects, including febrile neutropenia. The rates of secondary malignancies were low.

CONCLUSION

Both regimens as used in the present study are well tolerated and safe. The rates of severe taxane-related toxic effects and thrombocytopenia, although low overall, are significantly increased with the dose-dense sequential regimen.

Local radiotherapy induces homing of hematopoietic stem cells to the irradiated bone marrow

Local breast radiation therapy (RT) is associated with a 3-fold increased risk of secondary acute myeloid leukemia. As a first step in determining the mechanism(s) underlying this observation, we investigated the role of RT in mediating the active recruitment of hematopoietic stem cells (HSC) to the site of RT. Our results show in a mouse model that local RT delivered to the left leg causes preferential accumulation of bone marrow mononuclear cells to the irradiated site, with maximum signal intensity observed at 7 days post-RT. This is associated with a 4-fold higher number of donor-derived HSC present in the left leg, demonstrating recruitment of HSC to the site of RT. SDF-1, matrix metalloproteinase 2 (MMP-2), and MMP-9 expression is significantly increased in the irradiated bone marrow, and their inhibition significantly reduced HSC recruitment to the irradiated bone marrow. Our data show that local RT has significant systemic effects by recruiting HSC to the irradiated bone marrow site, a process mediated by SDF-1, MMP-2, and MMP-9. These results raise the possibility that the exposure of increased numbers of HSC at a local site to fractionated irradiation may increase the risk of leukemogenesis. Our data also suggest some opportunities for leukemia prevention in breast cancer patients undergoing RT.

Accelerated Intensity-Modulated Radiotherapy to Breast in Prone Position: Dosimetric Results

PURPOSE

To report the physics and dosimetry results of a trial of accelerated intensity-modulated radiotherapy to the whole breast with a concomitant boost to the tumor bed in patients treated in the prone position.

METHODS AND MATERIALS

Patients underwent computed tomography planning and treatment in the prone position on a dedicated treatment platform. The platform has an open aperture on the side to allow for the index breast to fall away from the chest wall. Noncontrast computed tomography images were acquired at 2.5- or 3.75-mm-thick intervals, from the level of the mandible to below the diaphragm. A dose of 40.5 Gy was delivered to the entire breast at 2.7-Gy fractions in 15 fractions. An additional dose of 0.5 Gy was delivered as a concomitant boost to the lumpectomy site, with a 1-cm margin, using inverse planning, for a total dose of 48 Gy in 15 fractions. No more than 10% of the heart and lung volume was allowed to receive >18 and >20 Gy, respectively.

RESULTS

Between September 2003 and August 2005, 91 patients were enrolled in the study. The median volume of heart that received > or =18 Gy was 0.5%, with a maximal value of 4.7%. The median volume of ipsilateral lung that received > or =20 Gy was 0.8%, with a maximum of 7.2%.

CONCLUSION

This technique for whole breast radiotherapy is feasible and enables an accelerated regimen in the prone position while sparing the lung and heart.

Acute myeloid leukaemia secondary to treatment with capecitabine for metastatic colorectal cancer

A 63-year-old woman was diagnosed with acute myelo-monocytic leukaemia, associated with MLL gene rearrangement, 16 months after completion of oral capecitabine for metastatic colon cancer. Capecitabine, recommended for use in metastatic breast and colon cancer and more recently as adjuvant treatment of colon cancer, has not previously been reported to be associated with secondary cancer.

Adjuvant chemotherapy for early-stage breast cancer

Systemic chemotherapy is an integral component of the adjuvant treatment strategy for women who have early-stage breast cancer and accounts for significant improvements in breast cancer-specific mortality. Decisions regarding adjuvant therapy are increasingly complex with the advent of new therapeutic strategies, a growing body of literature on the molecular biology and natural history of breast cancer, and advances in therapeutic techniques and early detection. Ultimately, the risk-benefit calculus will continue to evolve in response to these advances and one hopes that clinicians will soon be able to tailor treatment recommendations to the biology of an individual cancer and the needs of the affected individual.

Sequenced compared with simultaneous anthracycline and cyclophosphamide in high-risk stage I and II breast cancer: final analysis from INT-0137 (S9313)

PURPOSE

We conducted a phase III randomized study of two adjuvant treatment schedules of doxorubicin (A) and cyclophosphamide (C) in early-stage breast cancer to determine if administration of sequential single agents (A --> C) results in superior disease-free survival (DFS) and overall survival (OS) versus the same total dose given in combination (AC).

PATIENTS AND METHODS

High-risk node-negative or low-risk node-positive breast cancer patients received AC given: (arm I) concurrently (AC) doxorubicin 54 mg/m2 and cyclophosphamide 1.2 g/m2 intravenously (IV) every 3 weeks for six cycles; or (arm II) in sequence (A C) doxorubicin 40.5 mg/m2 IV days 1 and 2 every 3 weeks for four cycles followed by cyclophosphamide 2.4 gm/m2 IV every 2 weeks for three cycles. Total dose and duration were identical, but the intensity of each drug was increased on A C. Both arms included granulocyte colony-stimulating factor support and prophylactic antibiotics. All but premenopausal women with receptor negative tumors received tamoxifen after chemotherapy.

RESULTS

Between 1994 and 1997, 3,176 patients were randomly assigned. Arms were well balanced; 48% of eligible patients were node-negative and 48% were estrogen receptor-positive. No significant differences in OS or DFS were observed; 5-year estimates of OS (95% CI) were 88% (87% to 90%) on AC and 89% (87% to 91%) on A --> C. Grade 4 hematologic toxicity was greater on A --> C, but nonhematological grade 4 was similar.

CONCLUSION

The overall result does not support superiority of dose-intense sequenced single agents. The greater toxicity of higher doses of single agents does not support their sequential use.

Case 34: acute leukemia in a patient with a previous history of breast cancer

A 56-year-old woman presented with acute myeloid leukemia 3 years after presenting with carcinoma of the breast. Detailed investigations led to a precise diagnosis.

Myelodysplastic syndromes: the complexity of stem-cell diseases

The prevalence of patients with myelodysplastic syndromes (MDS) is increasing owing to an ageing population and increased awareness of these diseases. MDS represent many different conditions, not just a single disease, that are grouped together by several clinical characteristics. A striking feature of MDS is genetic instability, and a large proportion of cases result in acute myeloid leukaemia (AML). We Review three emerging principles of MDS biology: stem-cell dysfunction and the overlap with AML, genetic instability and the deregulation of apoptosis, in the context of inherited bone marrow-failure syndromes, and treatment-related MDS and AML.

Leukemia following breast cancer: an international population-based study of 376,825 women

PURPOSE

To quantify long-term temporal trends in the excess absolute risk (EAR) of secondary leukemia among breast cancer (BC) survivors, using multivariate analyses to evaluate the effects of subtype, age at BC diagnosis, attained age, and calendar year.

PATIENTS AND METHODS

We identified 376,825 1-year survivors of BC within 4 nationwide, population-based cancer registries in Sweden, Denmark, Finland, and Norway (1943-2001). Estimates of EAR (per 100,000 person-years) were modeled using Poisson regression methods and cumulative risks calculated using a competing risk model.

RESULTS

A total of 687 non-chronic lymphocytic leukemias (EAR = 9.05; 95% confidence interval (CI) = 7.5-10.7) was reported. Significantly elevated risks were observed for the first time for chronic myeloid leukemia (CML) (EAR = 2.06; 95% CI = 1.3-2.9) and acute lymphoblastic leukemia (ALL) (EAR = 0.62; 95% CI = 0.2-1.1), in addition to acute myeloid leukemia (AML) (EAR = 5.00; 95% CI = 3.9-6.2). Excesses of CML, ALL, AML and all leukemias combined persisted over 25 years after BC diagnosis. For all leukemias, EAR decreased with increasing calendar year (P = 0.04) of BC diagnosis. Risk for all leukemia and AML by calendar year of BC diagnosis depended on age at diagnosis. For women diagnosed with BC after 1985, the 10-year cumulative risk of leukemia for those diagnosed before and after age 50 was small, 0.10% and 0.14%, respectively.

CONCLUSIONS

Although secondary leukemia is a rare event, BC survivors experience statistically significant excesses for at least 25 years after diagnosis, including CML and ALL. Decreasing leukemia risks in recent calendar years likely reflect changes in treatment.