Randomized trial of cyclophosphamide, methotrexate, and fluorouracil chemotherapy added to tamoxifen as adjuvant therapy in postmenopausal women with node-positive estrogen and/or progesterone receptor-positive breast cancer: a report of the National Cancer Institute of Canada Clinical Trials Group. Breast Cancer Site Group

Adjuvant Treatment of Elderly Breast Cancer Patients: Offer the Best Chances of Cure

Background

Breast cancer remains the most common cancer in women and a leading cause of death. Elderly people have a higher incidence of breast cancer since it increases with age. Furthermore, the extended life expectancy and advances in imaging techniques have led to an increased number of cases. Guidelines concerning the management of this specific age group are rare, mainly due to underrepresentation of seniors in clinical trials. Moreover, increased frailty, comorbidities, and a poor performance status make it complex to determine the best therapeutic approach.

Summary

In this review, we attempt to summarize the current literature and aim to provide specific approaches and recommendations for prompt diagnosis, treatment, and management of breast cancer in the elderly.

Key Messages

The establishment of applicable protocols is imperative and efforts are being made in this direction. A careful geriatric assessment and adequate consultation should be the standard of care and patient's preferences should always be considered.

Capecitabine-Based Chemoendocrine Combination as First-Line Treatment for Metastatic Hormone-Positive Metastatic Breast Cancer: Phase 2 Study

BACKGROUND

Preclinical studies have suggested a synergistic effect of tamoxifen and capecitabine in estrogen receptor-positive cell lines. We evaluated the safety and efficacy of first-line chemoendocrine treatment in patients with metastatic breast cancer. Biochemical assessment was performed of serum levels of thymidine phosphorylase enzyme (TP), serum tamoxifen, hydroxytamoxifen, and 5-fluorouracil in relationship to efficacy.

PATIENTS AND METHODS

This prospective phase 2 interventional study studied patients with estrogen receptor-positive, HER2^- metastatic breast cancer who received either tamoxifen/capecitabine or letrozole/capecitabine as first-line treatment. The dose of capecitabine provided at 2000 mg per day continuously as a fixed dose.

RESULTS

Forty women with a median age of 49.3 years were enrolled. For the whole study group, median progression-free survival (PFS) was 10 months and median overall survival (OS) was 23.3 months. The overall response rate was 60% and the clinical benefit rate 82.5%. Progesterone receptor positivity was associated with significantly longer PFS (12 vs. 7 months, P = .021). The most frequent adverse events were palmar-plantar erythrodysesthesia (62.5%), fatigue (62.5%), diarrhea (30%), abdominal pain (12.5%), and constipation (10%). Changes in serum level of TP were not correlated to response to treatment, PFS, or OS. Higher serum levels of tamoxifen and hydroxytamoxifen were correlated with higher response rates and longer PFS but not OS.

CONCLUSION

Chemoendocrine treatment is well tolerated, with no evidence of contradictory effects between the combination components. However, the efficacy data need more validation.

Chemotherapy regimens in early breast cancer: major controversies and future outlook

The addition of adjuvant chemotherapy in early breast cancer improves overall survival by approximately 10%. Recommendations favor the use of anthracyclines and taxanes in patients with luminal B disease, while the use of an anthracycline, taxane and alkylating agent is recommended in triple-negative disease. In luminal B disease, the addition of chemotherapy to endocrine treatment depends on estrogen receptor expression and overall risk. Chemotherapy is not recommended in most patients with luminal A (highly hormone-sensitive and low proliferation) breast cancer. A major controversy is the addition of adjuvant chemotherapy to endocrine treatment in patients with estrogen receptor-positive breast cancer. In some of these patients, multigene signatures such as the 21-gene recurrence score may be a useful addition to histopathology. The introduction of molecular subtypes and gene signatures improves the complexity of early breast cancer treatment, and individual institutes have to find their policy based on their histopathological information and the availability of gene signatures.

A mechanistic study of the effect of doxorubicin/adriamycin on the estrogen response in a breast cancer model

OBJECTIVE

Estrogen treatment limits the cytotoxic effects of chemotherapy in estrogen receptor-positive (ER+) breast cancer cell lines, suggesting that estrogen pathway signaling may confer chemotherapeutic resistance. This study investigates the molecular responses of ER+ breast cancer cell lines to the chemotherapeutic agent, doxorubicin, in the presence or absence of estrogen.

METHODS

ER+ MCF-7 and T47-D cells were cultured in hormone-starved or estrogen-containing media with or without doxorubicin at concentrations mimicking the low concentrations seen in plasma and tumor microenvironments in humans following typical bolus administration. Protein levels, phosphorylations, and interactions of estrogen-signaling molecules were assessed following these treatments, as well the effects of ER signaling inhibitors on cell proliferation.

RESULTS

Surprisingly, estrogen and doxorubicin co-treatment markedly induced pro-growth alterations compared to doxorubicin alone and modestly enhanced estrogen alone-induced changes. Several inhibitors suppressed cell proliferation in the presence of doxorubicin and estrogen.

CONCLUSIONS

These findings demonstrate that molecular changes caused by doxorubicin in ER+ breast cancer cells can be reversed by estrogen, providing molecular evidence for the poorer responses of ER+ tumors to doxorubicin in the presence of physiologic estrogen levels. Our results also suggest that the addition of drugs targeting the ER, EGFR, the SFKs, MEK, PI3K, and/or the MMP proteins to a conventional chemotherapy regimen may improve chemosensitivity.

Advances in the understanding of the structure and function of ER-α36,a novel variant of human estrogen receptor-alpha

Estrogen receptors (ERs) belong to the nuclear receptor superfamily, whose members include ER-α66, ER-α36, ER-α46 and ER-β. Each receptor performs specific functions through binding with a specific ligand, such as estrogen. Recently, ER-α36, a novel variant of human estrogen receptor-alpha (ER-α), was identified and cloned. ER-α36 inhibits, in a dominant-negative manner, the transactivation of both the wild-type ER-α (ER-α66) and ER-β. As a predominantly membrane-based ER, ER-α36 mediates nongenomic estrogen signaling and is involved in the resistance of breast cancer to endocrine therapy, i.e., tamoxifen. This review summarizes recent studies on the structure and function of ER-α36 and the relationship of ER-α36 with cancer, with special emphasis on its function in the resistance of breast cancer to endocrine therapy.

Optimal sequence of implied modalities in the adjuvant setting of breast cancer treatment: an update on issues to consider

The adjuvant setting of early breast cancer treatment is an evolving field where different modalities must be combined to improve outcomes; moreover, quality of life of breast cancer survivors emerges as a new important parameter to consider, thus implying a better understanding of toxicities of these modalities. We have conducted a review focusing on the latest literature of the past 3 years, trying to evaluate the existing data on the maximum acceptable delay of radiotherapy when given as sole adjuvant treatment after surgery and the optimal sequence of all these modalities with respect to each other. It becomes evident radiotherapy should be given as soon as possible and within a time frame of 6-20 weeks. Chemotherapy is given before radiotherapy and hormone therapy. However, radiotherapy should be started within 7 months after surgery in these cases. Hormone therapy with tamoxifen might be given safely concomitantly or sequentially with radiotherapy although solid data are still lacking. The concurrent administration of letrozole and radiotherapy seems to be safe, whereas data on trastuzumab can imply only that it is safe to use concurrently with radiotherapy. Randomized comparisons of hormone therapy and trastuzumab administration with radiotherapy need to be performed.

Combinational treatment of gap junctional activator and tamoxifen in breast cancer cells

Tamoxifen is a drug of choice for endocrine-responsive breast tumor patients. However, tamoxifen resistance has become a major concern for the treatment of breast cancer. Combinational therapies of tamoxifen and different drugs are being frequently studied. In this study, we tested the efficacy of substituted quinolines (code name=PQ1; a gap junctional activator) in combination with tamoxifen in T47D cells. Colony growth assay was performed using soft agar to measure the colony growth, whereas cell proliferation was measured by the MTT assay in T47D cells. The level of Ki67, survivin, and BAX was measured using confocal microscopy along with western blot analysis. Apoptosis-bromodeoxyuridine triphosphate labeling was also examined in the induced treatment of T47D cells. We observed a 55% decrease in the colony growth in the presence of combination of PQ1 and tamoxifen, whereas tamoxifen alone had little effect. A combination of 10 micromol/l tamoxifen and 200 or 500 nmol/l PQ1 resulted in only 16% cell viability compared with controls at 48 h in T47D cells by the MTT assay. We found a significant increase in BAX protein at 1 h in the presence of 500 nmol/l PQ1 alone, 10 micromol/l tamoxifen alone, and the combination of PQ1 and tamoxifen. A two-fold increase was observed in active caspase 3 in the presence of combinational treatment of 10 micromol/l tamoxifen and 200 or 500 nmol/l PQ1. In addition, flow cytometric analysis showed a 50% increase in the number of apoptotic cells in the presence of the combination of tamoxifen and PQ1 compared with the control. Furthermore, the results show that combinational treatment of tamoxifen and PQ1 significantly reduces the expression of survivin in T47D cells. Gap junction inhibitor studies with carbenexolone were also performed confirming the role of gap junctions in cell proliferation and cell death. The combinational treatment of PQ1 and tamoxifen has a significant increase in BAX expression, caspase 3 activation, and DNA fragmentation. Tamoxifen alone and in combination with PQ1 showed a decrease in the expression of survivin, whereas PQ1 alone was shown to be independent of the survivin-mediated pathway. This suggests that an increase in gap junction activity can potentiate the effect of tamoxifen. The combinational treatment of tamoxifen and PQ1 also showed a significant decrease in cell viability compared with tamoxifen treatment alone. The gap junction inhibitor carbenexolone was shown to increase cell proliferation by increased cyclin D1 expression, MTT assay, and Ki67 expression. It further decreased cell death. This study shows for the first time that combinational treatment of tamoxifen and PQ1 (a gap junctional activator) can be used to potentiate apoptosis of T47D human breast cancer cells. Thus, a gap junctional activator, PQ1, could potentially alter either the length or dose of tamoxifen clinically used for breast cancer patients.

Adjuvant chemotherapy and timing of tamoxifen in postmenopausal patients with endocrine-responsive, node-positive breast cancer: a phase 3, open-label, randomised controlled trial

BACKGROUND

Tamoxifen is standard adjuvant treatment for postmenopausal women with hormone-receptor-positive breast cancer. We assessed the benefit of adding chemotherapy to adjuvant tamoxifen and whether tamoxifen should be given concurrently or after chemotherapy.

METHODS

We undertook a phase 3, parallel, randomised trial (SWOG-8814, INT-0100) in postmenopausal women with hormone-receptor-positive, node-positive breast cancer to test two major objectives: whether the primary outcome, disease-free survival, was longer with cyclophosphamide, doxorubicin, and fluorouracil (CAF) given every 4 weeks for six cycles plus 5 years of daily tamoxifen than with tamoxifen alone; and whether disease-free survival was longer with CAF followed by tamoxifen (CAF-T) than with CAF plus concurrent tamoxifen (CAFT). Overall survival and toxicity were predefined, important secondary outcomes for each objective. Patients in this open-label trial were randomly assigned by a computer algorithm in a 2:3:3 ratio (tamoxifen:CAF-T:CAFT) and analysis was by intention to treat of eligible patients. Groups were compared by stratified log-rank tests, followed by Cox regression analyses adjusted for significant prognostic factors. This trial is registered with ClinicalTrials.gov, number NCT00929591.

FINDINGS

Of 1558 randomised women, 1477 (95%) were eligible for inclusion in the analysis. After a maximum of 13 years of follow-up (median 8.94 years), 637 women had a disease-free survival event (tamoxifen, 179 events in 361 patients; CAF-T, 216 events in 566 patients; CAFT, 242 events in 550 patients). For the first objective, therapy with the CAF plus tamoxifen groups combined (CAFT or CAF-T) was superior to tamoxifen alone for the primary endpoint of disease-free survival (adjusted Cox regression hazard ratio [HR] 0.76, 95% CI 0.64-0.91; p=0.002) but only marginally for the secondary endpoint of overall survival (HR 0.83, 0.68-1.01; p=0.057). For the second objective, the adjusted HRs favoured CAF-T over CAFT but did not reach significance for disease-free survival (HR 0.84, 0.70-1.01; p=0.061) or overall survival (HR 0.90, 0.73-1.10; p=0.30). Neutropenia, stomatitis, thromboembolism, congestive heart failure, and leukaemia were more frequent in the combined CAF plus tamoxifen groups than in the tamoxifen-alone group.

INTERPRETATION

Chemotherapy with CAF plus tamoxifen given sequentially is more effective adjuvant therapy for postmenopausal patients with endocrine-responsive, node-positive breast cancer than is tamoxifen alone. However, it might be possible to identify some subgroups that do not benefit from anthracycline-based chemotherapy despite positive nodes.

FUNDING

National Cancer Institute (US National Institutes of Health).

Pharmacology and clinical applications of selective estrogen receptor modulators

Compounds that can be described as selective estrogen receptor modulators (SERMs) have expanded dramatically over the past two decades. The ability of SERMs to act as estrogens in certain tissues while remaining inert or acting as an anti-estrogen in other tissues has opened up opportunities for treating specific estrogen-modulated diseases without accepting the risk of systemic estrogen activity. SERM development has resulted in significant therapeutic advances for breast cancer, osteoporosis and potentially other diseases associated with the menopause. After the publication of the Women's Health Initiative, interest in compound selectivity that reduces menopausal symptoms while protecting bone, breast, uterus and the heart has increased. Future SERMs may also have a therapeutic profile that can be tailored to specific patient populations, including men. This review paper summarizes the characteristics of different SERMs from various pharmacological categories and the feasibility and scope of their use for a large range of disease/health conditions.

WITHDRAWN: Multi-agent chemotherapy for early breast cancer

BACKGROUND

There have been many randomised trials of adjuvant prolonged polychemotherapy among women with early breast cancer, and an updated overview of their results is presented.

OBJECTIVES

In this report, the Early Breast Cancer Trialists' Collaborative Group present their updated systematic overview (meta-analysis) of treatment with polychemotherapy.

SEARCH STRATEGY

Trial identification procedures for the EBCTCG overviews have been described elsewhere. See under "EBCTCG" in the Breast Cancer Collaborative Review Group module.

SELECTION CRITERIA

All randomised trials that began before 1990 and involved treatment groups that differed only with respect to the chemotherapy regimens that were being compared.

DATA COLLECTION AND ANALYSIS

In 1995, information was sought on each woman in any randomised trial that began before 1990 and involved treatment groups that differed only with respect to the chemotherapy regimens that were being compared. Analyses involved about 18,000 women in 47 trials of prolonged polychemotherapy versus no chemotherapy, about 6000 in 11 trials of longer versus shorter polychemotherapy, and about 6000 in 11 trials of anthracycline-containing regimens versus CMF (cyclophosphamide, methotrexate, and fluorouracil).

MAIN RESULTS

For recurrence, polychemotherapy produced substantial and highly significant proportional reductions both among women aged under 50 at randomisation (35% [SD 4] reduction; 2p<0.00001) and among those aged 50-69 (20% [SD 3] reduction; 2p<0.00001); few women aged 70 or over had been studied. For mortality, the reductions were also significant both among women aged under 50 (27% [SD 5] reduction; 2p<0.00001) and among those aged 50-69 (11% [SD 3] reduction; 2p=0.0001). The recurrence reductions emerged chiefly during the first 5 years of follow-up, whereas the difference in survival grew throughout the first 10 years. After standardisation for age and time since randomisation, the proportional reductions in risk were similar for women with node-negative and node-positive disease. Applying the proportional mortality reduction observed in all women aged under 50 at randomisation would typically change a 10-year survival of 71% for those with node-negative disease to 78% (an absolute benefit of 7%), and of 42% for those with node-positive disease to 53% (an absolute benefit of 11%). The smaller proportional mortality reduction observed in all women aged 50-69 at randomisation would translate into smaller absolute benefits, changing a 10-year survival of 67% for those with node-negative disease to 69% (an absolute gain of 2%) and of 46% for those with node-positive disease to 49% (an absolute gain of 3%). The age-specific benefits of polychemotherapy appeared to be largely irrespective of menopausal status at presentation, oestrogen receptor status of the primary tumour, and of whether adjuvant tamoxifen had been given. In terms of other outcomes, there was a reduction of about one-fifth (2p=0.05) in contralateral breast cancer, which has already been included in the analyses of recurrence, and no apparent adverse effect on deaths from causes other than breast cancer (death rate ratio 0.89 [SD 0.09]). The directly randomised comparisons of longer versus shorter durations of polychemotherapy did not indicate any survival advantage with the use of more than about 3-6 months of polychemotherapy. By contrast, directly randomised comparisons did suggest that, compared with CMF alone, the anthracycline-containing regimens studied produced somewhat greater effects on recurrence (2p=0.006) and mortality (69% vs 72% 5-year survival; log-rank 2p=0.02). But this comparison is one of many that could have been selected for emphasis, the 99% CI reaches zero, and the results of several of the relevant trials are not yet available.

AUTHORS' CONCLUSIONS

Some months of adjuvant polychemotherapy (eg, with CMF or an anthracycline-containing regimen) typically produces an absolute improvement of about 7-11% in 10-year survival for women aged under 50 at presentation with early breast cancer, and of about 2-3% for those aged 50-69 (unless their prognosis is likely to be extremely good even without such treatment). Treatment decisions involve consideration not only of improvements in cancer recurrence and survival but also of adverse side-effects of treatment, and this report makes no recommendations as to who should or should not be treated.

Treatment of breast cancer in older women

BACKGROUND

Breast carcinoma management in the elderly often differs from the management in younger women and there is considerable controversy about what constitutes appropriate cancer care for older women. This controversy is reflected in the persistence of age-dependent variations in care over time, with older women being less likely to receive definitive care for breast cancer. There has been a significant increase in the last years in the number of studies conducted in older patients with breast cancer. Although available age-specific clinical trials data demonstrate that treatment efficacy is not modified by age, this evidence is limited by the lack of inclusion of substantial numbers of older women, particularly those of advanced age and those with comorbidities.

METHOD

The literature-based evidence of the last 10 years was extensively reviewed on the main issues concerning the treatment of breast cancer in older women.

RESULTS

Surgical treatment in older patients has evolved from avoidance to mastectomy to breast-conserving surgery, similarly to younger patients. Given its negative effect on the quality of life, in the last few years the role of adjuvant radiotherapy has been questioned in elderly patients with breast cancer. Adjuvant chemotherapy benefit in older patients applies mainly to Estrogen-receptor-negative patients, while in Estrogen-receptor-positive patients a major role is played by endocrine treatment. New "elderly-friendly" drugs, that can help clinicians to reduce toxicity, are now available for breast cancer.

Breast Cancer in the Elderly

Screening and adjuvant postoperative therapies have increased survival among women with breast cancer. These tools are seldom applied in elderly patients, although the usually reported incidence of breast cancer is close to 50% in women 65 years or older, reaching 47% after 70 years in the updated Surveillance, Epidemiology, and End Results (SEER) database. Elderly breast cancer patients, even if in good medical health, were frequently excluded from adjuvant clinical trials. Women age 70 years who are fit actually have a median life expectancy of 15.5 years, ie, half of them will live much longer and will remain exposed for enough time to the potentially preventable risks of a relapse and specific death. In the last few years, a new concern about this issue has developed. Treatment now faces two major end points, as in younger women: to improve disease-free survival in the early stages, and to palliate symptoms in advanced disease. However, in both settings, the absolute benefit of treatment is critical because protecting quality of life and all its related aspects (especially functional status and independence), is crucial in older persons who have more limited life expectancy. Furthermore, the new hormonal compounds (aromatase inhibitors) and chemotherapeutic drugs (capecitabine, liposomal doxorubicin), are potentially less toxic than and equally as effective as older more established therapies. These new treatments bring new challenges including higher cost, and defining their benefit in elderly breast cancer must include an analysis of the cost/benefit ratio. These issues emphasize the urgent need to develop and support clinical trials for this older population of breast cancer patients both in the adjuvant and metastatic settings, a move that will take us from a prejudiced, age-based medicine to an evidence-based medicine.

Selection of chemotherapeutic drugs in adjuvant programs based on molecular profiles: Where do we stand?

Tumors have usually been classified by their morphologic appearances. Unfortunately, these current classification schemes have serious drawbacks. They are not able to stratify similar histopathological appearances that will follow significantly different clinical courses or respond differently to chemotherapy. The information that a specific molecular profile correlates with important clinical endpoints should permit physicians to take treatment decisions based on the molecular characteristics of each tumor. Lessons from the metastatic setting have been translated to the adjuvant setting, and several strategies have been evaluated in clinical trials. The expression of estrogen receptors (ER) in breast cancer enables physicians to make treatment decisions related to the use of hormonal manipulations. In this context, the challenge is to define a suitable subgroup of patients who will benefit from the addition of chemotherapy. Otherwise, the lack of ER expression predicts no benefit from hormonotherapy. In this setting chemotherapy plays a central role. The selection of the most appropriate regimen based on HER-2 status remains an uncertain strategy. However, the expression of the oncoprotein HER-2 has been linked to the probability of response to the target-designed monoclonal antibody trastuzumab. The role of trastuzumab in the adjuvant setting is supported by the early results of three large clinical trials presented at the American Society Clinical Oncology meeting in 2005. These trials have shown a striking impact of trastuzumab on the main endpoints such as disease-free survival and overall survival. In this context, the integration of trastuzumab with taxane and anthracycline-based-chemotherapy seems to be the appropriate choice. This review will combine data from breast cancer biology with clinical evidence coming from large phase III trials in the attempt to propose a molecular targeted approach to the adjuvant treatment strategy of early breast cancer patients.

Anastrozole is cost-effective vs tamoxifen as initial adjuvant therapy in early breast cancer: Canadian perspectives on the ATAC completed-treatment analysis

GOALS OF WORK

To conduct an economic analysis comparing tamoxifen and anastrozole (Arimidex) in the adjuvant treatment of hormone receptor-positive (HR+), post-menopausal early breast cancer patients.

MATERIALS AND METHODS

An economic model examined typical patients (64 years of age, HR+, 64% node negative) from the Arimidex, tamoxifen alone, or in combination (ATAC) trial over a lifetime horizon. Rates of events were derived from ATAC trial results. Post-trial event rates were drawn from the literature for tamoxifen; event rates for anastrozole were modified by the relative risks observed in the ATAC trial. Resource utilization was drawn from Statistics Canada's Population Health Model for breast cancer, supplemented by an expert panel. A public health care system perspective, 2004 Canadian prices and a 5% discount rate were employed.

RESULTS

Anastrozole-taking patients incurred additional hormonal treatment costs compared to tamoxifen-taking patients (incremental lifetime cost, 6,974 Canadian dollars per patient), partially offset by reduced downstream recurrences of breast cancer (1,143 Canadian dollars lifetime savings per patient) for a net incremental cost of 5,796 Canadian dollars per patient on anastrozole. The anastrozole-treated patients were projected to experience a 5.6% absolute risk reduction of first breast cancer recurrence and a 2.8% absolute risk reduction in breast cancer death. This corresponded to 30,000 Canadian dollars per life year gained and 28,000 Canadian dollars per quality-adjusted life year gained (95% confidence interval, 17,428 to 54,605 Canadian dollars). The results were affected by the duration and extent of anastrozole benefit under sensitivity analysis but remained cost-effective.

CONCLUSION

Compared to tamoxifen, anastrozole therapy is effective and cost-effective as initial adjuvant therapy in post-menopausal, HR+ early breast cancer patients.

Metabolism and transport of oxazaphosphorines and the clinical implications

The oxazaphosphorines including cyclophosphamide (CPA), ifosfamide (IFO), and trofosfamide represent an important group of therapeutic agents due to their substantial antitumor and immuno-modulating activity. CPA is widely used as an anticancer drug, an immunosuppressant, and for the mobilization of hematopoetic progenitor cells from the bone marrow into peripheral blood prior to bone marrow transplantation for aplastic anemia, leukemia, and other malignancies. New oxazaphosphorines derivatives have been developed in an attempt to improve selectivity and response with reduced toxicity. These derivatives include mafosfamide (NSC 345842), glufosfamide (D19575, beta-D-glucosylisophosphoramide mustard), NSC 612567 (aldophosphamide perhydrothiazine), and NSC 613060 (aldophosphamide thiazolidine). This review highlights the metabolism and transport of these oxazaphosphorines (mainly CPA and IFO, as these two oxazaphosphorine drugs are the most widely used alkylating agents) and the clinical implications. Both CPA and IFO are prodrugs that require activation by hepatic cytochrome P450 (CYP)-catalyzed 4-hydroxylation, yielding cytotoxic nitrogen mustards capable of reacting with DNA molecules to form crosslinks and lead to cell apoptosis and/or necrosis. Such prodrug activation can be enhanced within tumor cells by the CYP-based gene directed-enzyme prodrug therapy (GDEPT) approach. However, those newly synthesized oxazaphosphorine derivatives such as glufosfamide, NSC 612567 and NSC 613060, do not need hepatic activation. They are activated through other enzymatic and/or non-enzymatic pathways. For example, both NSC 612567 and NSC 613060 can be activated by plain phosphodiesterase (PDEs) in plasma and other tissues or by the high-affinity nuclear 3'-5' exonucleases associated with DNA polymerases, such as DNA polymerases and epsilon. The alternative CYP-catalyzed inactivation pathway by N-dechloroethylation generates the neurotoxic and nephrotoxic byproduct chloroacetaldehyde (CAA). Various aldehyde dehydrogenases (ALDHs) and glutathione S-transferases (GSTs) are involved in the detoxification of oxazaphosphorine metabolites. The metabolism of oxazaphosphorines is auto-inducible, with the activation of the orphan nuclear receptor pregnane X receptor (PXR) being the major mechanism. Oxazaphosphorine metabolism is affected by a number of factors associated with the drugs (e.g., dosage, route of administration, chirality, and drug combination) and patients (e.g., age, gender, renal and hepatic function). Several drug transporters, such as breast cancer resistance protein (BCRP), multidrug resistance associated proteins (MRP1, MRP2, and MRP4) are involved in the active uptake and efflux of parental oxazaphosphorines, their cytotoxic mustards and conjugates in hepatocytes and tumor cells. Oxazaphosphorine metabolism and transport have a major impact on pharmacokinetic variability, pharmacokinetic-pharmacodynamic relationship, toxicity, resistance, and drug interactions since the drug-metabolizing enzymes and drug transporters involved are key determinants of the pharmacokinetics and pharmacodynamics of oxazaphosphorines. A better understanding of the factors that affect the metabolism and transport of oxazaphosphorines is important for their optional use in cancer chemotherapy.

Endocrine therapy--current benefits and limitations

Endocrine therapy is a valuable option for the treatment of postmenopausal women with estrogen receptor (ER)-positive breast cancer due to its demonstrated efficacy and favorable safety profile. Although tamoxifen has been the established treatment for more than 20 years its long-term use is associated with several tolerability concerns and may lead to increased risk of endometrial cancer and thromboembolic complications. In addition, many patients who initially respond to treatment with endocrine agents such as tamoxifen eventually relapse with resistant disease. Sequential use of endocrine therapies is often used in patients as resistance to individual agents develops. Several endocrine approaches have been developed that deprive the tumor of estrogen stimulation, either by directly modulating the ER-signaling pathway or by lowering serum or tumor concentrations of estrogen. In the classic pathway of estrogen signal transduction, the steroid hormone binds to its intracellular ER, triggering a cascade of events that ultimately leads to altered gene transcription. More recently, it has become apparent that ER activation can also occur via estrogen-independent receptor activation or by non-nuclear action through cell surface receptors. Consequently, molecular cross-talk exists between the ER and growth factor signaling cascades, which is a key factor in de novo and acquired resistance to endocrine therapy. Inappropriate activation of growth factor signaling can readily promote endocrine therapy failure in breast cancer cells, either by overriding the growth-inhibitory properties of antiestrogenic drugs or by establishment of a new self-propagating autocrine loop that efficiently drives resistant cell growth. Fulvestrant is a new type of ER antagonist with no agonist effects that binds, blocks and causes degradation of the ER. As multiple signaling pathways are involved in the activation of ER, the use of agents such as fulvestrant that directly target the ER and lead to both degradation of the receptor and abrogation of ER signaling may prevent or delay the development of absolute endocrine resistance. In addition, combining antiestrogenic drugs with inhibitors of cell signaling molecules to target both the ER and growth factor signaling pathways is likely to provide a means of delaying endocrine therapy resistance, leading the way to more effective breast cancer treatment.

The choice of systemic adjuvant therapy in receptor-positive early breast cancer

Patients with endocrine-responsive breast cancer represent a distinct population for which tailored adjuvant treatments are needed. Endocrine therapy is mandatory for this population. For premenopausal patients, ovarian ablation or tamoxifen can be recommended; the combination of both, as well as the combination of ovarian ablation and aromatase inhibitors is under investigation. For postmenopausal patients, tamoxifen for 5 years is the 'standard of care'. Anastrozole can be recommended for patients with a contraindication to tamoxifen. The addition of 5 years of letrozole after 5 years of tamoxifen has yielded benefits in terms of disease-free survival. The sequential use of tamoxifen and exemestane was superior to tamoxifen for 5 years. However, in both studies, long-term toxicity is still not fully evaluated. The addition of chemotherapy to endocrine treatment can be recommended for patients at high risk of relapse and in young patients. Chemotherapy should consist of 3-6 cycles of cyclophosphamide, methotrexate, 5-fluorouracil or of an anthracycline-containing regimen. The addition of taxanes cannot be routinely recommended in this population. Endocrine treatment should start after completion of chemotherapy.

Tamoxifen--what next?

Most patients with advanced breast cancer (ABC) ultimately die due to disease progression. Consequently, treatments for ABC are predominantly palliative in nature and, therefore, the tolerability profile of a given treatment is particularly relevant in these patients. While cytotoxic chemotherapy and endocrine therapy exhibit efficacy in hormone-sensitive, advanced disease, it is endocrine therapy that combines efficacy with minimal acute toxicity. Tamoxifen has been the chosen endocrine therapy for postmenopausal, hormone-sensitive, ABC for over 20 years. More recently, new endocrine agents with different mechanisms of action from tamoxifen have been introduced. Evidence indicates that the aromatase inhibitors anastrozole (Arimidex; AstraZeneca; Wilmington, DE), letrozole (Femara; Novartis Pharmaceuticals Corp.; East Hanover, NJ) and exemestane (Aromasin; Pharmacia Corp.; Peapack, NJ) offer superior efficacy and tolerability to tamoxifen in the first-line treatment of postmenopausal, hormone-sensitive ABC. Similarly, after tamoxifen failure, fulvestrant (Faslodex; AstraZeneca), a new estrogen receptor (ER) antagonist that downregulates the ER, is at least as effective as anastrozole, is well tolerated, and is not cross-resistant with tamoxifen. Unlike tamoxifen, fulvestrant has no known agonist effects. The sequential use of such agents may prolong the time during which endocrine therapies can be used, thereby avoiding the more acute toxicities associated with cytotoxic chemotherapy. Indeed, a series of studies has shown that this sequential use is a relevant, active, and well-tolerated option. Establishing the comparative efficacies and optimal sequences that incorporate the newer endocrine agents will be central in determining the future role of hormonal therapy in ABC; the results of this work will determine the relative place of tamoxifen in what is a rapidly changing therapeutic environment.

Adjuvant Therapy in Elderly Patients with Breast Cancer

The elderly population has been neglected by the traditional approach to clinical breast cancer research. Elderly women have been underrepresented in breast cancer clinical trials, with the majority of studies being restricted to patients aged < 70 years. Elderly patients frequently have comorbidities and/or impaired organ function. These facts may often lead to death from causes other than cancer, thus nullifying any possible benefit of adjuvant treatment; furthermore, they render extrapolation of standard treatment recommendations to the elderly potentially hazardous, particularly with respect to chemotherapy. Therefore, specific clinical trials are needed to investigate adjuvant treatments tailored for the heterogeneous older population.

Adjuvant cytotoxic and endocrine therapy in pre- and postmenopausal patients with breast cancer and one to nine infiltrated nodes: five-year results of the Hellenic Cooperative Oncology Group randomized HE 10/92 study

SUMMARY

The present randomized phase III trial was designed to detect a 15% benefit in relapse-free survival (RFS) or overall survival (OS) from the incorporation of adjuvant tamoxifen to the combination of CNF [cyclophosphamide, 500 mg/m2; mitoxantrone (Novantrone), 10 mg/m2; fluorouracil, 500 mg/m2 chemotherapy and ovarian ablation in premenopausal patients with node-positive breast cancer and conversely from the incorporation of CNF chemotherapy to adjuvant tamoxifen in node-positive postmenopausal patients. From April 1992 until March 1998, 456 patients with operable breast cancer and one to nine infiltrated axillary nodes entered the study. Premenopausal patients were treated with six cycles of CNF chemotherapy followed by ovarian ablation with monthly injections of triptoreline 3.75 mg for 1 year (Group A, 84 patients) or the same treatment followed by 5 years of tamoxifen (Group B, 92 patients). Postmenopausal patients received 5 years of tamoxifen (Group C, 145 patients) or 6 cycles of CNF followed by 5 years of tamoxifen (Group D, 135 patients). Adjuvant radiation was administered to all patients with partial mastectomy. After a median follow-up period of 5 years, 125 patients (27%) relapsed and 79 (17%) died. The 5-year actuarial RFS for premenopausal patients was 65% in Group A and 68% in Group B (p = 0.86) and for postmenopausal patients 70% in Group C and 67% in Group D (p = 0.36). Also, the respective OS rates were 77% and 80% (p = 0.68) for premenopausal and 84% and 78% (p = 0.10) for postmenopausal patients. Severe toxicities were infrequently seen, with the exception of leukopenia (18%), among the 311 patients treated with CNF. In conclusion, the present study failed to demonstrate a 15% difference in RFS in favor of node-positive premenopausal patients treated with an additional 5 years of tamoxifen after CNF adjuvant chemotherapy and ovarian ablation. Similarly, six cycles of CNF preceding 5 years of tamoxifen did not translate to a 15% RFS benefit in node-positive postmenopausal patients.

Evidence-based indications for postmastectomy irradiation

The ASCO guidelines panel found that PMRT reduces the risks of both local-regional recurrence and distant recurrence, and improves survival rates for patients with invasive breast cancer with involved axillary lymph nodes receiving systemic therapy. The benefits of PMRT, however, vary with regards to particular patient subsets (such as those defined by the number of involved axillary nodes). The panel agreed that PMRT is indicated routinely for patients with four or more positive axillary nodes, tumors larger than 5 cm in size, or locally advanced cancers. There was insufficient evidence for the panel to make recommendations or suggestions for the use of PMRT for patients with T1-2 tumors with one to three positive axillary nodes or for all patients receiving neoadjuvant systemic therapy. Physicians and patients are encouraged to participate in randomized trials exploring such issues, such as the ongoing intergroup study for patients with one to three positive axillary nodes.

A phase III trial of sequential adjuvant chemotherapy for operable breast carcinoma: final analysis with 10-year follow-up

BACKGROUND

The current study was performed to assess whether sequential potentially noncross-resistant chemotherapy prolongs disease-free survival (DFS) and overall survival (OS) in patients with operable breast carcinoma.

METHODS

Seven hundred eighty-nine patients were registered and followed for a median of 10 years. They were treated in two groups. In Group 1, patients age < 50 years or age > 50 years but with either negative or unknown estrogen receptor (ER) status were randomized to receive 6 cycles of 5-fluorouracil, doxorubicin, and cyclophosphamide (FAC) alone or followed by 4 cycles of methotrexate and vinblastine (MV). In Group 2, patients age > or = 50 years with ER-positive disease were randomized to receive either tamoxifen or combination chemotherapy (FAC + MV) for 10 cycles. Analysis was performed according to allocated treatment (intention to treat), with all randomized patients included.

RESULTS

In Group 1 there were no significant differences with regard to DFS or OS between the two treatment arms. The DFS at 5 years was 0.70 and 0.76, respectively, for FAC compared with FAC+MV (P = 0.26). The OS was similar for both groups (0.84 vs. 0.83). It is interesting to note that there was a statistically nonsignificant trend for improved DFS in the FAC + MV arm for patients who were ER-positive. In Group 2, tamoxifen alone led to more prolonged DFS compared to FAC+MV (0.78 vs. 0.66, respectively) but this did not reach statistical significance (P = 0.28). OS also was associated with a trend (P = 0.86) toward prolonged survival for the tamoxifen arm compared with the FAC+MV arm (0.85 vs. 0.74, respectively).

CONCLUSIONS

The results of the current trial concerning sequential adjuvant chemotherapy for operable breast carcinoma, which to our knowledge contains the longest follow-up presented to date, failed to demonstrate any additional benefit from the addition of 4 cycles of MV to 6 cycles of FAC chemotherapy.

Effects of low dose tamoxifen on normal breast tissue from premenopausal women

The aim of this study was to determine the effects of low doses of tamoxifen (5 and 10mg/day) for 50 days compared with the standard dose (20 mg/day) on breast biomarkers measured in normal breast tissue from premenopausal patients. A randomised double-blind study was performed using tissue from 56 premenopausal women with a diagnosis of fibroadenoma of the breast. Excisional biopsy was performed on the 50th day of therapy. Normal breast tissue samples were collected during surgery. The patients were divided in groups: A (placebo, n=11); group B (5 mg, n=16), group C (10 mg, n=14) and group D (20 mg, n=15). In this cross-sectional study, differences in the expression of Oestrogen Receptor alpha (ERalpha), Progesterone Receptor (PR), Ki-67, apoptotic bodies and mitotic index between the different groups after treatment can be seen on the normal breast tissue. We believe that a lower dose of tamoxifen could reduce the side-effects associated with treatment without affecting its chemopreventive activity in the breast.

Significant increase in breast conservation in 16 years of trials conducted by the Austrian Breast & Colorectal Cancer Study Group

OBJECTIVE

To confirm evidence that breast-conserving treatment (BCT) does not impair the prognosis in breast cancer patients as compared to mastectomy and to argue that it be regarded as the treatment of choice in stage I and II disease.

SUMMARY BACKGROUND DATA

Scientifically, survival rates in breast cancer have been shown to be stage-dependent, but independent of the extent of surgical breast tissue removal, as long as the resection margins are free of tumor infiltration.

METHODS

Between 1984 and 1997, six different trials conducted by the Austrian Breast & Colorectal Cancer Study Group accrued a total of 4,259 women with hormone-responsive disease. The authors selected and compared three patient groups (n = 3,316) according to pathologic stage, age, and the surgical procedure applied.

RESULTS

Over this interval, the BCT rate in the premenopausal node-positive subgroup experienced a highly significant increase from 27.2% to 73.2% overall. In the group of postmenopausal node-negative patients, the BCT rate grew significantly by 37.3% to 77.3% in total. With an overall BCT rate growing from 22.5% to 56.8% in postmenopausal node-positive women, those presenting with T1 tumors saw a significant increase from 35.1% to 65.9%. Mortality and local recurrence rates proved stable or even decreased considerably over time and in all subgroups.

CONCLUSIONS

The presented outcome of BCT rates, significantly improved over this 16-year period and in no way counterbalanced by higher local recurrence or death rates, reflects an excellent example of surgical quality control. BCT can safely be regarded as the standard of therapy for T1 and increasingly for T2 disease. Especially in multi-institutional adjuvant breast cancer trials, the highest priority should be given to breast-conserving procedures.

Patterns of failure in a randomized trial of adjuvant chemotherapy in postmenopausal patients with early breast cancer treated with tamoxifen

BACKGROUND

We studied the effect of adjuvant anthracycline-based chemotherapy in postmenopausal patients with resected early breast cancer treated with adjuvant tamoxifen.

PATIENTS AND METHODS

The trial included 835 patients with either axillary lymph node involvement, or tumors with histological grade II or III. They were randomized after local surgery to receive either tamoxifen (TAM group) or tamoxifen plus chemotherapy (TAM-CT group) consisting of six courses of 5-fluorouracil, doxorubicin and cyclophosphamide (FAC), or 5-fluorouracil, epidoxorubicin and cyclophosphamide (FEC). Radiotherapy was given after completion of adjuvant chemotherapy in the TAM-CT group and after surgery in the TAM group.

RESULTS

The 5-year disease-free survival (DFS) rates were 73% in the TAM group and 79% in the TAM-CT group (log-rank test, P = 0.06). The 5-year overall survival rates were 82% and 87%, respectively (P = 0.06). The 5-year distant metastasis rates were 22% and 16% (P = 0.02), and the 5-year local recurrence rates were 6% and 4%, respectively (P = 0.23). There were no significant differences for contralateral breast cancer or other new primary malignancies. Chemotherapy tended to be more effective for patients who had tumors without estrogen receptors (trend test, P = 0.05).

CONCLUSIONS

Anthracycline-based chemotherapy administered to postmenopausal patients receiving adjuvant tamoxifen gave a borderline significant benefit on overall and DFS, mainly by a reduction in distant metastases. Delaying radiotherapy after six courses of chemotherapy did not affect local control after up to 10 years of follow-up.

Side effects of chemotherapy and combined chemohormonal therapy in women with early-stage breast cancer

The decision to receive chemotherapy or chemohormonal therapy involves careful consideration of both the potential benefits and possible risks of therapy. There are substantial short- and long-term side effects from chemotherapy. By convention, short-term side effects include those toxic effects encountered during chemotherapy, while long-term side effects include later complications of treatment arising after the conclusion of adjuvant chemotherapy. These side effects vary, depending on the specific agents used in the adjuvant regimen as well as on the dose used and the duration of treatment. There is also considerable variability in side effect profile across individuals. This review will focus on the short- and long-term toxicity seen with the most commonly used adjuvant chemotherapy and chemohormonal therapy regimens.

Progress in systemic chemotherapy of primary breast cancer: an overview

Substantial progress has been made in the multidisciplinary management of primary breast cancer during the last 30 years. Adjuvant chemotherapy has been shown to significantly reduce the annual risk of cancer recurrence and mortality, and these effects persist even 15 years after diagnosis. Combination chemotherapy is superior to single-agent therapy and anthracycline-containing regimens. Those that combine an anthracycline with 5-fluorouracil and cyclophosphamide are more effective than regimens without an anthracycline. Six cycles of a single regimen appear to provide optimal benefit. Dose reductions below the standard range are associated with inferior results. Dose increases that require growth factor or hematopoietic stem cell support are under investigation; at this time, the existing results provide no compelling reason to use this strategy outside a clinical trial. Regimens using fixed crossover designs with two non-cross-resistant regimens are being evaluated. The addition of a taxane to anthracycline-containing regimens is currently under intense scrutiny, and preliminary analysis of the first three clinical trials has shown encouraging, albeit not compelling, results. For patients with estrogen receptor-positive breast cancer, the sequential administration of chemotherapy and 5 years of tamoxifen therapy provides additive benefits. No compelling evidence exists to combine ovarian ablation with chemotherapy. Most side effects and toxic effects are self-limited, although premature menopause requires monitoring and preventive interventions to preserve bone mineral density. The small risk of acute leukemia is of concern, and additional research to develop safer regimens is clearly indicated. The overall effect of optimal local/regional treatment combined with an anthracycline-containing adjuvant chemotherapy and a taxane (and, for patients with estrogen receptor-positive tumors, 5 years of tamoxifen therapy) is a greater than 50% reduction in annual risks of recurrence of and death from breast cancer. For most patients at intermediate or high risk of cancer recurrence, the benefits of adjuvant chemotherapy exceed by far its unwanted effects.

The feasibility of classical cyclophosphamide, methotrexate, 5-fluorouracil (CMF) for pre- and post-menopausal node-positive breast cancer patients in a Belgian multicentric trial: a study of consistency in relative dose intensity (RDI) and cumulative doses across institutions

BACKGROUND

Classical cyclophosphamide, methotrexate, 5-fluorouracil (CMF) including oral cyclophosphamide is still considered an important adjuvant chemotherapy regimen in patients with early breast cancer (BC). Concern has been raised regarding the feasibility of this regimen, especially in postmenopausal patients.

PATIENTS AND METHODS

254 pre- and post-menopausal node-positive BC patients aged < or = 70 years received six cycles of CMF in the context of a Belgian multicentric phase III trial of adjuvant chemotherapy. CMF dose and schedule were as follows: cyclophosphamide 100 mg/m2 p.o. on days 1 to 14, methotrexate 40 mg/m2 intravenously (i.v.) on days 1 and 8, 5-fluorouracil 600 mg/ml i.v. on days 1 and 8; cycles q. 28 days. The relative dose intensity (RDI) was calculated as the ratio between the delivered DI and the planned DI. We also analysed the RDI in two subgroups of patients with age > or = 50 years or < 50 years.

RESULTS

Overall, the percentage of patients ending the six cycles of the planned CMF regimen was 90%. The mean RDI achieved in the population of 254 patients was 90% (range 8% to 129%). The subgroup analysis of patients aged > or = 50 years and < 50 years showed that 81% and 76% of patients, respectively, received > or = 80% of the planned chemotherapy dose intensity (P = 0.33). No statistically significant difference was found between the percentage of patients who received a RDI < 80% and the participating institutions (P = 0.50).

CONCLUSIONS

The classical CMF regimen was a feasible regimen in the context of a multicentric trial, in which academic institutions as well as community hospitals participated. No substantial differences in RDI and cumulative doses were found in relation to a patient's age and the participating institution.

Multi-agent chemotherapy for early breast cancer

BACKGROUND

There have been many randomised trials of adjuvant prolonged polychemotherapy among women with early breast cancer, and an updated overview of their results is presented.

OBJECTIVES

In this report, the Early Breast Cancer Trialists' Collaborative Group present their updated systematic overview (meta-analysis) of treatment with polychemotherapy.

SEARCH STRATEGY

Trial identification procedures for the EBCTCG overviews have been described elsewhere. See under "EBCTCG" in the Breast Cancer Collaborative Review Group module.

SELECTION CRITERIA

All randomised trials that began before 1990 and involved treatment groups that differed only with respect to the chemotherapy regimens that were being compared.

DATA COLLECTION AND ANALYSIS

In 1995, information was sought on each woman in any randomised trial that began before 1990 and involved treatment groups that differed only with respect to the chemotherapy regimens that were being compared. Analyses involved about 18,000 women in 47 trials of prolonged polychemotherapy versus no chemotherapy, about 6000 in 11 trials of longer versus shorter polychemotherapy, and about 6000 in 11 trials of anthracycline-containing regimens versus CMF (cyclophosphamide, methotrexate, and fluorouracil).

MAIN RESULTS

For recurrence, polychemotherapy produced substantial and highly significant proportional reductions both among women aged under 50 at randomisation (35% [SD 4] reduction; 2p <0.00001) and among those aged 50-69 (20% [SD 3] reduction; 2p <0.00001); few women aged 70 or over had been studied. For mortality, the reductions were also significant both among women aged under 50 (27% [SD 5] reduction; 2p <0.00001) and among those aged 50-69 (11% [SD 3] reduction; 2p=0.0001). The recurrence reductions emerged chiefly during the first 5 years of follow-up, whereas the difference in survival grew throughout the first 10 years. After standardisation for age and time since randomisation, the proportional reductions in risk were similar for women with node-negative and node-positive disease. Applying the proportional mortality reduction observed in all women aged under 50 at randomisation would typically change a 10-year survival of 71% for those with node-negative disease to 78% (an absolute benefit of 7%), and of 42% for those with node-positive disease to 53% (an absolute benefit of 11%). The smaller proportional mortality reduction observed in all women aged 50-69 at randomisation would translate into smaller absolute benefits, changing a 10-year survival of 67% for those with node-negative disease to 69% (an absolute gain of 2%) and of 46% for those with node-positive disease to 49% (an absolute gain of 3%). The age-specific benefits of polychemotherapy appeared to be largely irrespective of menopausal status at presentation, oestrogen receptor status of the primary tumour, and of whether adjuvant tamoxifen had been given. In terms of other outcomes, there was a reduction of about one-fifth (2p=0.05) in contralateral breast cancer, which has already been included in the analyses of recurrence, and no apparent adverse effect on deaths from causes other than breast cancer (death rate ratio 0.89 [SD 0.09]). The directly randomised comparisons of longer versus shorter durations of polychemotherapy did not indicate any survival advantage with the use of more than about 3-6 months of polychemotherapy. By contrast, directly randomised comparisons did suggest that, compared with CMF alone, the anthracycline-containing regimens studied produced somewhat greater effects on recurrence (2p=0.006) and mortality (69% vs 72% 5-year survival; log-rank 2p=0.02). But this comparison is one of many that could have been selected for emphasis, the 99% CI reaches zero, and the results of several of the relevant trials are not yet available.

REVIEWER'S CONCLUSIONS

Some months of adjuvant polychemotherapy (eg, with CMF or an anthracycline-containing regimen) typically produces an absolute improvement of about 7-11% in 10-year survival for women aged under 50 at presentation with early breast cancer, and of about 2-3% for those aged 50-69 (unless their prognosis is likely to be extremely good even without such treatment). Treatment decisions involve consideration not only of improvements in cancer recurrence and survival but also of adverse side-effects of treatment, and this report makes no recommendations as to who should or should not be treated.

Tamoxifen plus chemotherapy versus tamoxifen alone as adjuvant therapies for node-positive postmenopausal women with early breast cancer: a stochastic economic evaluation

BACKGROUND

There remains uncertainty around the appropriate choice of adjuvant therapies to offer postmenopausal women with node-positive early breast cancer.

OBJECTIVE AND STUDY DESIGN

To present the results derived from a discrete event simulation (DES) model that compared tamoxifen plus chemotherapy versus tamoxifen alone in node-positive postmenopausal women diagnosed with early breast cancer.

METHODS

The data populating the model were mainly derived from the existing literature, which was analysed to specify probability distributions describing the uncertainty around the true value of each input parameter. The specified probability distributions facilitated the stochastic analysis of the decision model, whereby distributions of the model's outputs [aggregate costs and quality-adjusted life years (QALYs)] were estimated.

RESULTS

The baseline results show that the addition of chemotherapy to tamoxifen in this patient group is relatively cost effective (under pound 4000 per additional QALY), but the distribution of the incremental cost-effectiveness ratio shows a wide range, including 10% of observations in which tamoxifen dominates tamoxifen plus chemotherapy.

CONCLUSIONS

The results demonstrate the intuitive nature of stochastic evaluations of healthcare technologies, which may ease decision-makers' interpretation of cost-effectiveness results.

Meta-analysis of adjuvant cyclophosphamide/methotrexate/5-fluorouracil chemotherapy in postmenopausal women with estrogen receptor-positive, node-positive breast cancer

Conflicting results have been published regarding the efficacy of adjuvant cyclophosphamide/methotrexate/5-fluorouracil (CMF)-type chemotherapy in postmenopausal, estrogen receptor (ER)-positive women. The Oxford overview suggests real but limited benefit of any chemotherapy in this group of patients but avoids analyzing smaller subsets. We wished to better quantitate the benefit of adding CMF to tamoxifen in postmenopausal ER-positive women with tumor involvement of axillary lymph nodes. Six randomized studies comparing CMF plus tamoxifen to tomoxifen alone in postmenopausal, ER-positive, node-positive women have been published since 1992. They include 2368 patients. We performed a meta-analysis of 6 endpoints: survival, disease-free survival, locoregional recurrence, distant recurrence, contralateral breast recurrence, and thromboembolic complications. There was a statistically significant increase in disease-free survival from the addition of CMF-type chemotherapy to tamoxifen in this population; the absolute risk of relapse was reduced by 5.5% at 5 years. Effects of locoregional recurrence were greater than those on overall recurrence. No significant survival benefit was observed.

Postmastectomy radiotherapy: clinical practice guidelines of the American Society of Clinical Oncology

OBJECTIVE

To determine indications for the use of postmastectomy radiotherapy (PMRT) for patients with invasive breast cancer with involved axillary lymph nodes or locally advanced disease who receive systemic therapy. These guidelines are intended for use in the care of patients outside of clinical trials.

POTENTIAL INTERVENTION

The benefits and risks of PMRT in such patients, as well as subgroups of these patients, were considered. The details of the PMRT technique were also evaluated.

OUTCOMES

The outcomes considered included freedom from local-regional recurrence, survival (disease-free and overall), and long-term toxicity.

EVIDENCE

An expert multidisciplinary panel reviewed pertinent information from the published literature through July 2000; certain investigators were contacted for more recent and, in some cases, unpublished information. A computerized search was performed of MEDLINE data; directed searches based on the bibliographies of primary articles were also performed.

VALUES

Levels of evidence and guideline grades were assigned by the Panel using standard criteria. A "recommendation" was made when level I or II evidence was available and there was consensus as to its meaning. A "suggestion" was made based on level III, IV, or V evidence and there was consensus as to its meaning. Areas of clinical importance were pointed out where guidelines could not be formulated due to insufficient evidence or lack of consensus.

RECOMMENDATIONS

The recommendations, suggestions, and expert opinions of the Panel are described in this article.

VALIDATION

Seven outside reviewers, the American Society of Clinical Oncology (ASCO) Health Services Research Committee members, and the ASCO Board of Directors reviewed this document.

Preoperative endocrine therapy for older women with breast cancer: renewed interest in an old idea

BACKGROUND

Tamoxifen as sole therapy (primary tamoxifen therapy) was investigated in the 1970s and 1980s as an alternative to surgery for older patients with breast cancer. While the majority of primary breast tumors responded to tamoxifen, long-term local disease control was poor. The use of primary tamoxifen therapy is therefore restricted to frail, elderly, and infirm patients who cannot tolerate surgery. In contrast, short-term preoperative endocrine therapy to downstage estrogen receptor-positive (ER+) tumors is under increasing scrutiny as a nontoxic neoadjuvant approach for older women.

METHODS

The literature on primary tamoxifen therapy and preoperative endocrine therapy was reviewed to construct an opinion piece on the feasibility and safety of preoperative endocrine therapy.

RESULTS

A review of nine phase II trials and a meta-analysis of two randomized trials suggest that the initial response rates to preoperative endocrine therapy will exceed 50% to 60% for patients with ER+ disease. A short delay in surgery to administer 3 to 4 months of preoperative endocrine therapy is unlikely to compromise long-term outcomes.

CONCLUSIONS

Preoperative endocrine therapy is a logical approach for older patients with ER+ disease as a well-tolerated means to increase the rate of breast-conserving surgery. Several clinical trials comparing tamoxifen with selective aromatase inhibitors in the preoperative setting have been conducted, and the results are expected soon. These studies will determine if a large multicenter national trial of preoperative endocrine therapy should be conducted.

Treatment of supratentorial glioblastoma multiforme with radiotherapy and a combination of BCNU and tamoxifen: a phase II study

From May 1990 to November 1994, 70 consecutive patients suffering from glioblastoma multiforme were treated following surgery with conventional radiotherapy and adjuvant IV BCNU administered alone or in combination with tamoxifen. Twenty-five patients received BCNU alone (control group A) while 24 patients also received 40 mg of tamoxifen (TMX) PO daily (group B) and 21 received 100 mg of TMX PO daily (group C). There were no significant differences between the 3 groups concerning age, type of resection and median post-operative Karnofsky performance status (KPS). Blood toxicity over grade II occurred in 33.5% of patients receiving TMX versus 12% of patients treated with BCNU alone (p < 0.05). Deep venous thrombosis complications were observed in 4 patients of each TMX group, whereas they were not observed in the control group (p < 0.04). Median time to tumor progression (MTTP) was 35 weeks in the control group and 27 weeks in both TMX groups B and C. Median survival time (MST) was 56, 66 and 51 weeks, respectively. These results suggest that the addition of TMX to standard treatment of glioblastomas does not affect the time to tumor progression and overall survival but may increase the risk of deep venous thrombosis or nitrosourea-induced blood toxicity.

Cancer, thrombosis, and anticoagulants

Rapid progress has been made recently in our understanding of the pathogenesis of coagulation activation in malignancy and mechanisms by which the coagulation mechanism may control malignant growth. Idiopathic thromboembolic disease may be the sentinel presentation in patients subsequently diagnosed with malignancy. Thrombosis complicating the course of malignancy may be notoriously difficult to treat, but the introduction of the low-molecular-weight heparins has greatly improved management and may obviate the need for invasive approaches, such as the use of inferior vena cava filters, in many cases. Tantalizing clues from clinical trials of anticoagulant therapy in cancer have suggested that components of coagulation pathways may support tumor growth. Many of these can be intercepted using drugs that are well known and non-toxic. The importance of performing high-quality controlled clinical trials that build on past studies and on data from basic research cannot be overemphasized.

Burdens and benefits of adjuvant cyclophosphamide, methotrexate, and fluorouracil and tamoxifen for elderly patients with breast cancer: the International Breast Cancer Study Group Trial VII

PURPOSE

Information on the tolerability and efficacy of adjuvant chemoendocrine therapy for older women is limited. We studied these issues using the data collected as part of the International Breast Cancer Study Group Trial VII.

PATIENTS AND METHODS

Postmenopausal women with operable, node-positive breast cancer were randomized to receive either tamoxifen alone for 5 years (306 patients) or tamoxifen plus three consecutive cycles of classical cyclophosphamide (100 mg/m(2) orally days 1 to 14), methotrexate (40 mg/m(2) intravenous days 1 and 8), and fluorouracil (600 mg/m(2) intravenous days 1 and 8) every 28 days (CMF; 302 patients). The median follow-up was 8.0 years.

RESULTS

Among the 299 patients who received at least one dose of CMF, women 65 years of age or older (n = 76) had higher grades of toxicity compared with women less than 65 years old (n = 223) (P =.004). More women in the older age group compared with the younger women experienced grade 3 toxicity of any type (17% v 7%, respectively), grade 3 hematologic toxicity (9% v 5%, respectively), and grade 3 mucosal toxicity (4% v 1%, respectively). Older patients also received less than their expected CMF dose compared with younger postmenopausal women (P =.0008). The subjective burdens of treatment, however, were similar for younger and older patients based on quality-of-life measures (performance status, coping, physical well-being, mood, and appetite). For older patients, the 5-year disease-free survival (DFS) rates were 63% for CMF plus tamoxifen and 61% for tamoxifen alone (hazards ratio [HR], 1.00; 95% confidence interval [CI], 0.65 to 1.52; P =.99). For younger patients, the corresponding 5-year DFS rates were 61% and 53% (HR, 0.70; 95% CI, 0.53 to 0.91; P =.008), but the test for heterogeneity of CMF effect according to age group was not statistically significant. The reduced effectiveness of CMF among older women could not be attributed to dose reductions according to dose received.

CONCLUSION

CMF tolerability and effectiveness were both reduced for older patients compared with younger postmenopausal node-positive breast cancer patients who received tamoxifen for 5 years. The development and evaluation of less toxic and more effective chemotherapy regimens are required for high-risk elderly patients.