Tumor-specific expression of vascular endothelial growth factor receptor 2 but not vascular endothelial growth factor or human epidermal growth factor receptor 2 is associated with impaired response to adjuvant tamoxifen in premenopausal breast cancer.

PURPOSE: Vascular endothelial growth factor A (VEGF-A) and vascular endothelial growth factor receptor 2 (VEGFR2) are often coexpressed in breast cancer, and potentially affect cellular pathways and key proteins such as the estrogen receptor (ER) targeted by endocrine treatment. We therefore explored the association between adjuvant tamoxifen treatment in breast cancer and expression of VEGF-A and VEGFR2, as well as human epidermal growth factor receptor 2 (HER2), which represents a candidate gene product involved in tamoxifen resistance. PATIENTS AND METHODS: Immunohistochemical expression of tumor-specific VEGF-A, VEGFR2, and HER2 was evaluated in tumor specimens from premenopausal breast cancer patients randomly assigned to 2 years of tamoxifen or no treatment (n = 564), with 14 years of follow-up. Hormone receptor status was determined in 96% of the tumors. RESULTS: VEGF-A, VEGFR2, and HER2 were assessable in 460, 472, and 428 of the tumors, respectively. In patients with ER-positive and VEGFR2-low tumors, adjuvant tamoxifen significantly increased recurrence-free survival (RFS; [HR] hazard ratio for RFS, 0.53; P = .001). In contrast, tamoxifen treatment had no effect in patients with VEGFR2-high tumors (HR for RFS, 2.44; P = .2). When multivariate interaction analyses were used, this difference in treatment efficacy relative to VEGFR2 expression status was statistically significant for both ER-positive (P = .04) plus ER-positive and progesterone receptor-positive tumors. We found no significant difference in tamoxifen treatment effects in relation to VEGF-A or HER2 status. CONCLUSION: Tumor-specific expression of VEGFR2 was associated with an impaired tamoxifen effect in hormone receptor-positive premenopausal breast cancer. Tamoxifen in combination with VEGFR2 inhibitors might be a novel treatment approach for VEGFR2-expressing breast cancer, and such a treatment might restore the tamoxifen response.     

High progesterone receptor expression correlates to the effect of adjuvant tamoxifen in premenopausal breast cancer patients.

PURPOSE: Tamoxifen has long been the drug of choice in adjuvant endocrine therapy of steroid hormone receptor-positive breast cancer, and it still remains important due to its well-documented beneficial effect. Hormone receptor status is often reported as "positive" or "negative" using 10% positive nuclei as a cutoff. In this study, we aimed to assess whether a further subclassification of hormone receptor status could enhance the treatment predictive value. EXPERIMENTAL DESIGN: The immunohistochemical expression of estrogen receptor (ER) and progesterone receptor (PR) was quantified in tissue microarrays with tumors from 500 premenopausal breast cancer patients previously included in a randomized trial of adjuvant tamoxifen compared with an untreated control group. RESULTS: Our findings show a gradually increasing tamoxifen effect in tumors with >10% ER-positive nuclei. However, when analyzing tamoxifen response according to various PR fractions, we found that it was primarily patients with tumors showing >75% PR-positive nuclei that responded to tamoxifen treatment, with an improved recurrence-free [relative risk, 0.42 (0.25-0.70); P = 0.001] as well as overall [relative risk, 0.49 (0.28-0.84); P = 0.010] survival. CONCLUSIONS: Adjuvant tamoxifen improved recurrence-free and overall survival for premenopausal patients with tumors showing >75% PR-positive nuclei. No effect could be shown in tumors with fewer PR-positive nuclei. The PR was a stronger predictor of treatment response than the ER. Based on these findings, we suggest the implementation of a fractioned rather than dichotomized immunohistochemical evaluation of hormone receptors in clinical practice, possibly with greater emphasis on the PR than the ER.     

High p27Kip1 expression predicts superior relapse-free and overall survival for premenopausal women with early-stage breast cancer receiving adjuvant treatment with tamoxifen plus goserelin.

PURPOSE: To determine the predictive value of p27Kip1 in premenopausal women with early-stage hormone receptor-positive breast cancer. PATIENTS AND METHODS: We retrospectively examined tumor specimens from 512 patients with breast cancer who were enrolled onto Austrian Breast and Colorectal Cancer Study Group (ABCSG) Trial 5. In this trial, premenopausal, hormone receptor-positive breast cancer patients with stage I and II disease were randomly assigned to receive either 5 years of tamoxifen plus 3 years of goserelin or six cycles of cyclophosphamide, methotrexate, and fluorouracil. p27Kip1 expression was assessed by immunohistochemistry, and its association with clinical outcome was determined. Statistical analyses were performed to test for interaction between p27Kip1 status and treatment. RESULTS: High p27Kip1 expression (nuclear p27Kip1 staining in >/= 50% of tumor cells) independently predicted superior relapse-free survival (RFS) and overall survival (OS) in both the total study population (RFS: relative risk [RR], 0.53; 95% CI, 0.34 to 0.82; P =.004; OS: RR, 0.29; 95% CI, 0.15 to 0.58; P <.001) and patients treated with combination endocrine therapy (RFS: RR, 0.32; 95% CI, 0.16 to 0.63; P =.001; OS: RR, 0.16; 95% CI, 0.05 to 0.53; P =.003). The interaction between p27Kip1 expression and treatment was statistically significant for RFS (P =.04) but not for OS (P =.27). CONCLUSION: High p27Kip1 expression was an independent predictor of responsiveness to hormonal therapy and thus may be useful for the selection of premenopausal women with early-stage hormone receptor-positive breast cancer for adjuvant combination endocrine therapy.     

Clinical role of multidrug resistance protein 1 expression in chemotherapy resistance in early-stage breast cancer: the Austrian Breast and Colorectal Cancer Study Group.

PURPOSE: The multidrug resistance protein 1 (MRP1) is expressed in human breast cancer cells and may contribute to the clinical drug resistance of breast cancer patients. Therefore, we determined the impact of MRP1 expression on the clinical outcome of adjuvant therapy in patients with early-stage breast cancer. PATIENTS AND METHODS: Immunostaining for MRP1 was performed on tissue sections from 516 premenopausal, hormone receptor-positive breast cancer patients with stage I and II disease. Statistical analyses were performed to assess the effect of MRP1 expression on survival and to test for interaction between MRP1 expression and treatment. RESULTS: MRP1 expression independently predicted shorter relapse-free survival (RFS) and overall survival (OS) in patients treated with cyclophosphamide, methotrexate, and fluorouracil (CMF; RFS: hazard ratio [HR] = 1.48; 95% CI, 1.16 to 1.88; P = .002; OS: HR = 1.82; 95% CI, 1.10 to 3.01; P = .02), but it did not predict shorter RFS and OS in patients who received tamoxifen plus goserelin (RFS: HR = 0.99; 95% CI, 0.74 to 1.31; P = .9; OS: HR = 0.68; 95% CI, 0.40 to 1.15; P = .1). Tests for interaction between MRP1 expression and treatment were statistically significant for both RFS (P = .04) and OS (P = .006). CONCLUSION: Our data suggest that MRP1 expression plays an important role in the clinical resistance to adjuvant CMF chemotherapy but does not seem to affect response to adjuvant endocrine treatment with tamoxifen plus goserelin. Thus, MRP1 may be a useful marker for the selection of patients with early-stage breast cancer for the appropriate adjuvant therapy after prospective confirmatory evaluation.     

Sequential hormonal therapy for metastatic breast cancer after adjuvant tamoxifen or anastrozole

The use of adjuvant endocrine therapy in the treatment of hormone receptor-positive, early breast cancer has become important in both pre- and postmenopausal women. Tamoxifen has been the principal adjuvant hormonal therapy in pre- and postmenopausal women with hormone receptor-positive breast cancer for nearly 20 years. Recent data in premenopausal women suggest benefit from ovarian ablation with or without tamoxifen. Early results from the 'Arimidex', Tamoxifen, Alone or in Combination (ATAC) trial have demonstrated that the third-generation, selective aromatase inhibitor (AI) anastrozole ('Arimidex') is a suitable alternative adjuvant therapy for postmenopausal women with hormone receptor-positive disease. After recurrence or relapse on adjuvant endocrine therapy, responses to the sequential use of additional endocrine agents are common. The increase in the number of options now available for adjuvant therapy will have important implications for the selection of the optimal sequence of endocrine agents in the treatment of recurrent breast cancer. Menopausal status is an important factor in determining the endocrine therapy that a patient receives. For premenopausal women, tamoxifen and/or a luteinizing hormone-releasing hormone agonist such as goserelin ('Zoladex') are both options for adjuvant endocrine treatment. After progression on adjuvant and first-line tamoxifen, ovarian ablation is an appropriate second-line therapy. For premenopausal women who have undergone ovarian ablation, the use of third-line therapy with an AI becomes possible. For postmenopausal women, a wide choice of endocrine treatment options is available and an optimal sequence has yet to be determined. Options for first-line therapy of metastatic disease include an AI for women who have received adjuvant tamoxifen or tamoxifen for patients who have received adjuvant anastrozole. In addition, data suggest that fulvestrant ('Faslodex'), a novel estrogen receptor (ER) antagonist that downregulates the ER protein and has no known agonist effects, is a promising therapeutic option that has shown efficacy in the treatment of postmenopausal women with advanced breast cancer. Other agents that may be used in the sequence include the steroidal AI exemestane and the progestin megestrol acetate. The widening range of adjuvant endocrine options therefore represents an opportunity to prolong patient benefits in the treatment of hormone receptor-positive breast cancer, and will require the further refinement of the optimal sequence of endocrine agents for the treatment of recurrent breast cancer.     

Oophorectomy and tamoxifen adjuvant therapy in premenopausal Vietnamese and Chinese women with operable breast cancer.

PURPOSE: In 1992, the Early Breast Cancer Trialists' Collaborative Group reported that a meta-analysis of six randomized trials in European and North American women begun from 1948 to 1972 demonstrated disease-free and overall survival benefit from adjuvant ovarian ablation. Approximately 350,000 new cases of breast cancer are diagnosed annually in premenopausal Asian women who have lower levels of estrogen than western women. PATIENTS AND METHODS: From 1993 to 1999, we recruited 709 premenopausal women with operable breast cancer (652 from Vietnam, 47 from China) to a randomized clinical trial of adjuvant oophorectomy and tamoxifen (20 mg orally every day) for 5 years or observation and this combined hormonal treatment on recurrence. At later dates estrogen- and progesterone-receptor protein assays by immunohistochemistry were performed for 470 of the cases (66%). RESULTS: Treatment arms were well balanced. With a median follow-up of 3.6 years, there have been 84 events and 69 deaths in the adjuvant treatment group and 127 events and 91 deaths in the observation group, with 5-year disease-free survival rates of 75% and 58% (P =.0003 unadjusted; P =.0075 adjusted), and overall survival rates of 78% and 70% (P =.041 unadjusted) for the adjuvant and observation groups, respectively. Only patients with hormone receptor-positive tumors benefited from the adjuvant treatment. In Vietnam, for women unselected for hormone receptor status, a cost-effectiveness analysis suggests that this intervention costs $350 per year of life saved. CONCLUSION: Vietnamese and Chinese women with hormone receptor-positive operable breast cancer benefit from adjuvant treatment with surgical oophorectomy and tamoxifen.     

A pitfall in the survival benefit of adjuvant chemotherapy for node- and hormone receptor-positive patients with breast cancer: the paradoxical role of Bcl-2 oncoprotein (review)

The survival benefit of adjuvant chemotherapy in node-positive patients with breast cancer compared with surgery alone has been established. The survival benefit differs considerably between hormone receptor-positive and -negative patients, and it is believed that the effectiveness of adjuvant chemotherapy can be increased by hormonal therapy with tamoxifen. In the present review, we discuss the rationale behind the effectiveness of combination treatment with anticancer drugs and tamoxifen in terms of the paradoxical role of Bcl-2 in apoptosis in breast cancer. The survival benefit between receptor-positive and -negative patients was assessed using previous reports of randomized controlled studies for postoperative adjuvant chemotherapy in node-positive breast cancer. Tamoxifen induces the anti-apoptotic gene, Bcl-2, by its effect on estradiol (E2), via an E2-response element in the promotor region of Bcl-2. The efficicacy of chemoendocrine therapy was assessed in terms of the influence of tamoxifen on the effect of anticancer drugs. Adjuvant chemotherapy, including anthracycline and non-anthracycline based regimens, has an overall survival benefit in node-positive breast cancer, with a 23.5% reduction in the annual odds of recurrence and a 15% reduction in mortality (P<0.00001). A comparison of the reduction of the relative risk indicates that the survival benefit in receptor-negative patients is superior to that in receptor-positive patients by approximately 3-fold. Further, in contrast to receptor-negative patients, there is no additional benefit from paclitaxel over doxorubicin and cyclophosphamide (AC) in receptor-positive patients. The possible reasons that the chemotherapy benefit in receptor-positive patients is small and marginal are the following: i) concurrent treatment or pretreatment with tamoxifen can increase plasma E2 levels in premenopausal patients, thereby inducing Bcl-2 in residual cancer cells, which might decrease drug-sensitivity in combination with chemotherapy; ii) induction of Bcl-2 might be involved predominantly in the resistance to taxanes, the cytotoxic action of which targets Bcl-2. Co-treatment or pretreatment with tamoxifen for adjuvant therapy might decrease the efficacy of anticancer drugs, an effect that is mediated by induction of Bcl-2, especially in premenopausal patients with node-positive breast cancer. Treatment with anticancer drugs should be followed by treatment with tamoxifen to produce a survival benefit from combination therapy in receptor-positive patients.     

A randomized study of adjuvant treatments for operable breast cancer patients stratified by estrogen receptor and menopausal status

According to estrogen receptor (ER) and menopausal status, operable breast cancer patients were randomized for adjuvant endocrine therapy with tamoxifen (TAM) in premenopausal patients, after oophorectomy (OVEX), chemotherapy, CHEM (mitomycin C+ oral cyclophosphamide), or chemo-endocrine therapy (TAM + CHEM). Some 1579 patients were entered in the trial between 9, 1978 and 12, 1991, with a median follow-up of 10 years. In ER-positive, premenopausal patients there were no significant differences in relapse-free (RFS) or overall survival (OS) among the OVEX + TAM, CHEM, and CHEM + TAM arms. On the contrary, in ER-positive, post-menopausal patients, the chemoendocrine therapy showed a significantly better OS (p = 0.0254) with a trend of better RFS (p = 0.0674), as compared with TAM or CHEM groups. ER-negative, premenopausal patients showed no significant differences in RFS or OS between CHEM and CHEM + TAM arms. In ER-negative, postmenopausal patients, there was a non-significantly better RFS (p = 0.0888) and a significantly better OS (p = 0.0332) in CHEM + TAM group than in the CHEM alone group. These results suggest that ER and menopausal status are important criteria to select early breast cancer patients for adjuvant treatments.     

HER2 status in hormone receptor positive premenopausal primary breast cancer adds prognostic, but not tamoxifen treatment predictive, information

BACKGROUND: Overexpression of human epidermal growth factor receptor 2 (HER2) or amplification of its gene is a prognostic factor in primary breast cancer and a predictor for tamoxifen treatment efficacy in oestrogen receptor (ER) positive disease. In the present study we explored a defined cohort of breast cancer patients included in a randomised trial in order to assess prognostic and tamoxifen treatment information yielded by HER2 status. METHODS: Premenopausal breast cancer patients with stage II tumours (n = 564) were included and allocated to 2 years of adjuvant tamoxifen treatment versus no adjuvant treatment. ER, progesterone receptor (PR) status and HER2 status was determined by immunohistochemistry using a tissue microarray. HER2 amplification was analysed by fluorescent in situ hybridisation and tumours being amplified and/or HER2 3+ were considered HER2+. HER2 status was evaluable in 83% of the patients and 12.6% were HER2+. In untreated patients, HER2 was a negative prognostic factor in ER+ patients, HR 2.95; 95% CI: 1.61-5.38, p < 0.001, but not in ER- patients, HR 0.67; 95% CI: 0.28-1.61, p = 0.4, and a significant interaction between the two markers was found, p < 0.01. HER2 status was not related to tamoxifen treatment efficacy in ER+ patients (term of interaction p = 0.95). When stratifying for PR status, similar results were achieved. DISCUSSION: HER2+ and ER+ breast cancer constituted a subgroup of tumours with poor prognosis in premenopausal breast cancer, whereas no treatment interaction was found between HER2 status and tamoxifen in ER+ tumours. The poor prognosis in HER2+ and ER+ patients may interfere with the interpretation of HER2 data in non-randomised trials of adjuvant tamoxifen.     

Postoperative adjuvant chemotherapy followed by adjuvant tamoxifen versus nil for patients with operable breast cancer: a randomised phase III trial of the European Organisation for Research and Treatment of Cancer Breast Group

BackgroundThe contribution of adjuvant tamoxifen in breast cancer patients after receiving adjuvant chemotherapy is not fully established. We investigated the impact of tamoxifen, given sequentially after completion of adjuvant chemotherapy in patients with operable breast cancer.Patients and methodsBetween March 1991 and June 1999, 1863 women with stages I–IIIA operable breast cancer who had undergone surgery and completed six cycles of adjuvant combination chemotherapy with either CMF, CAF, CEF, FAC or FEC were randomised to receive either tamoxifen 20 mg daily for 3 years or no further treatment. Irrespective of menstrual status and hormone receptor content of the primary tumour, patients were stratified by institute, chemotherapy scheme and age (above 50 years or younger). The main end-point was to detect a 5% increase in the 5 year survival (from 80% to 85%) in favour of antioestrogen therapy. Secondary end-points were relapse free survival (RFS), local control, incidence of second primary breast cancer and correlation of results with hormone receptor content.ResultsAfter exclusion of all patients from three sites because of inadequate documentation, a total of 1724 patients (93%) were analysed (Tam 861 and Control 863). At a median follow-up of 6.5 years, 5-year RFS on tamoxifen was 73% versus 67% in controls (p = 0.035). No difference was seen in overall survival. The benefit of tamoxifen therapy was mainly seen in the subgroup of patients with histologically documented positive axillary nodes (5-year RFS on tamoxifen 71% versus 64% in the control group, p = 0.044) and in patients with tumours expressing the ER and PR positive phenotype (5-year RFS on tamoxifen 77% versus 70% in the control group, p = 0.014).ConclusionsTamoxifen administered for 3 years after completion of adjuvant chemotherapy in this otherwise unselected group of patients for endocrine sensitivity had a limited impact on relapse and had no detectable effect on overall survival. The beneficial effect of tamoxifen is mainly confined to the subgroup of patients with node-positive disease and to patients with tumours expressing the ER and PR positive phenotype.     

The role of tumor receptor status in choosing adjuvant therapy for breast cancer patients of reproductive age]

Estrogen (ER) and progesterone (PR) receptor levels were assayed in primary tumor samples from 271 premenopausal patients suffering T1,2N1M0 (stage II) breast cancer. Four clinical groups were identified according to steroid receptor levels in which results of adjuvant treatment (chemotherapy or complex treatment) were assessed. ER and PR positivity was associated with longer disease-free and overall survival. Adjuvant hormone therapy proved beneficial in ER+PR+ tumor patients. The latter group was also characterized by a lower relapse rate, particularly, in those aged over 40. It is recommended that: (1) T1,2N1M0 breast cancer patients be given adjuvant chemotherapy whatever tumor receptor status, (2) these patients should not be given adjuvant hormone therapy unless tumor receptor status has been established since prophylactic oophorectomy and subsequent hormone therapy are not justified for operable breast cancer, (3) complex therapy be administered to premenopausal patients aged over 40 years with ER+PR+ tumors only, and (4) PR-positivity be considered a good predictor of hormone sensitivity of cancer.     

Randomized adjuvant trial of tamoxifen and goserelin versus cyclophosphamide, methotrexate, and fluorouracil: evidence for the superiority of treatment with endocrine blockade in premenopausal patients with hormone-responsive breast cancer--Austrian Breast and Colorectal Cancer Study Group Trial 5.

PURPOSE: Effective adjuvant treatment modalities in premenopausal breast cancer patients today include chemotherapy, ovariectomy, and tamoxifen administration. The purpose of Austrian Breast and Colorectal Cancer Study Group Trial 5 was to compare the efficacy of a combination endocrine treatment with standard chemotherapy. PATIENTS AND METHODS: Assessable trial subjects (N = 1,034) presenting with hormone-responsive disease were randomized to receive either 3 years of goserelin plus 5 years of tamoxifen or six cycles of cyclophosphamide, methotrexate, and fluorouracil (CMF). Stratification criteria included tumor stage and grade, number of involved nodes, type of surgery, and steroid hormone receptor content. Relapse-free survival (RFS) was defined as time from randomization to first relapse, local recurrence, or contralateral incidence, and overall survival (OS) as time to date of death. RESULTS: With a 60-month median follow-up, 17.2% of patients in the endocrine group and 20.8% undergoing chemotherapy developed relapses. Local recurrences emerged in 4.7% and 8.0%, respectively. RFS and local recurrence-free survival differed significantly in favor of endocrine therapy (P =.037 and P =.015), with a similar trend observed in OS (P =.195). CONCLUSION: Overall, our data suggest that the goserelin-tamoxifen combination is significantly more effective than CMF in the adjuvant treatment of premenopausal patients with stage I and II breast cancer.     

Delayed adjuvant tamoxifen: Ten-year results of a collaborative randomized controlled trial in early breast cancer (TAM-02 trial)

Aim:Immediate adjuvant tamoxifen reduces disease recurrence andimproves survival in patients with early breast cancer. However, is it toolate to administer tamoxifen to patients who have already undergone treatment,but were unable to benefit from this adjuvant therapy? The French NationalCancer Centers (FNCLCC) have investigated the efficacy of delayed tamoxifenadministration in a randomized controlled trial. Patients and methods:From September 1986 to October 1989, womenwith primary breast cancer, who had undergone surgery, radiotherapy, and/orreceived adjuvant chemotherapy but not hormone therapy more than two yearsearlier, were randomized to receive either 30 mg/day tamoxifen or notreatment. The 10-year disease-free and overall survival rates of the twogroups of patients and of various subgroups were determined according to theKaplan–Meyer method and compared by the log-rank test. Results:This intention-to-treat analysis comprised 250 women inthe tamoxifen group and 244 in the control group. Patient characteristics(age, T stage, number of positive nodes, receptor status, and interval sincetumor treatment) were comparable in both groups. Delayed adjuvant tamoxifensignificantly improved overall survival only in node-positive patients and inpatients with estrogen receptor-positive (ER+) or progesteronereceptor-positive (PR+) tumors. Disease-free survival, however, wassignificantly improved in the global population and in several patientsubgroups (node-positive, ER+, PR+). Patients in whom the interval betweenprimary treatment and delayed adjuvant tamoxifen was greater than five yearsalso had significantly improved disease-free survival. Conclusions:Overall and disease-free survival results indicatethat delayed adjuvant tamoxifen administration (30 mg/day) is justified inwomen with early breast cancer, even if this treatment is initiated two ormore years after primary treatment.     

Adjuvant systemic therapy of early stage breast cancer

Opinion statement Adjuvant chemotherapy reduces the risk of recurrence and mortality in patients with early stage breast cancer. Anthracycline-based regimens are the most widely used standard in the United States. The inclusion of the taxanes into adjuvant chemotherapy programs offers an improvement in disease-free survival rates and probably overall survival rates compared to an anthracycline-based regimen alone. Although adjuvant chemotherapy is effective in all age groups, the magnitude of benefit is greatest in younger premenopausal patients. Treatment decisions need to be individualized. Dose-dense chemotherapy approaches are promising and can be considered an option for patients with early stage breast cancer. Adjuvant tamoxifen therapy should be administered for 5 years in patients with hormone receptor-positive breast cancer. Adjuvant tamoxifen should be administered after the completion of adjuvant chemotherapy. Data from the ATAC (Arimidex, tamoxifen, alone, or in combination) trial provide a compelling argument for choosing anastrozole as adjuvant endocrine therapy in postmenopausal women with hormone receptor-positive early stage breast cancer. Long-term follow-up of patients is necessary to determine the effects of chronic aromatase inhibitor treatment on bone density, cognitive function, and other endpoints.     

Luteinizing hormone-releasing hormone agonists in premenopausal hormone receptor-positive breast cancer

Ovarian function suppression for the treatment of premenopausal breast cancer was first used in the late 19th century. Traditionally, ovarian function suppression had been accomplished irreversibly via irradiation or surgery, but analogues of the luteinizing hormone-releasing hormone (LH-RH) have emerged as reliable and reversible agents for this purpose, especially the LH-RH agonists. Luteinizing hormone-releasing hormone antagonists are in earlier stages of development in breast cancer and are not currently in clinical use. Luteinizing hormonereleasing hormone agonists act by pituitary desensitization and receptor downregulation, thereby suppressing gonadotrophin release. Limited information is available comparing the efficacies of the depot preparations of various agonists, but pharmacodynamic studies have shown comparable suppressive capabilities on estradiol and luteinizing hormone. At present, only monthly goserelin is Food and Drug Administration-approved for the treatment of estrogen receptor-positive, premenopausal metastatic breast cancer in the United States. Luteinizing hormone-releasing hormone agonists have proven to be as effective as surgical oophorectomy in premenopausal advanced breast cancer. They offer similar outcomes compared with tamoxifen, but the endocrine combination appears to be more effective than LH-RH agonists alone. In the adjuvant setting, LH-RH agonists versus no therapy reduce the annual odds of recurrence and death in women aged>50 years with estrogen receptor-positive tumors. Luteinizing hormone-releasing hormone agonists alone or in combination with tamoxifen have shown disease-free survival rates similar to chemotherapy with CMF (cyclophosphamide/methotrexate/5-fluorouracil). Outcomes of chemotherapy with or without LH-RH agonists are comparable, though a few trials favor the combination in young premenopausal women (aged<40 years). Adjuvant LH-RH agonists with or without tamoxifen might be as efficacious as tamoxifen alone, and the additional benefit from chemotherapy is unclear. Adequately powered studies are now studying the relative merits of combining adjuvant tamoxifen or aromatase inhibitors with ovarian function suppression, the additional benefits of adding ovarian function suppression to chemotherapy, and the need for adjuvant chemotherapy for women treated with combined ovarian function suppression and anti-estrogen therapy.     

Randomized trial of low-dose chemotherapy added to tamoxifen in patients with receptor-positive and lymph node-positive breast cancer.

PURPOSE: To evaluate the outcome in patients with stage II hormone receptor-positive breast cancer treated or not treated with low-dose, short-term chemotherapy in addition to tamoxifen in terms of disease-free and overall survival. PATIENTS AND METHODS: A total of 613 patients were randomized to receive either low-dose chemotherapy (doxorubicin 20 mg/m(2) and vincristine 1 mg/m(2) on day 1; cyclophosphamide 300 mg/m(2); methotrexate 25 mg/m(2); and fluorouracil 600 mg/m(2) on days 29 and 36 intravenously) or no chemotherapy in addition to 20 mg of tamoxifen orally for 2 years. A third group without any treatment (postmenopausal patients only) was terminated after the accrual of 79 patients due to ethical reasons. RESULTS: After a median follow-up period of 7.5 years, the addition of chemotherapy did not improve the outcome in patients as compared with those treated with tamoxifen alone, neither with respect to disease-free nor overall survival. Multivariate analysis of prognostic factors for disease-free survival revealed menopausal status, in addition to nodal status, progesterone receptor, and histologic grade as significant. Both untreated postmenopausal and tamoxifen-treated premenopausal patients showed identical prognoses significantly inferior to the tamoxifen-treated postmenopausal cohort. Prognostic factors for overall survival in the multivariate analysis showed nodal and tumor stage, tumor grade, and hormone receptor level as significant. CONCLUSION: Low-dose chemotherapy in addition to tamoxifen does not improve the prognosis of stage II breast cancer patients with hormone-responsive tumors. Tamoxifen-treated postmenopausal patients show a significantly better prognosis than premenopausal patients, favoring the hypothesis of a more pronounced effect of tamoxifen in the older age groups.     

Tree-based model for breast cancer prognostication.

PURPOSE: To define prognostic groups for recurrence-free survival in breast cancer, assess relative effects of prognostic factors, and examine the influence of treatment variations on recurrence-free survival in patients with similar prognostic-factor profiles. PATIENTS AND METHODS: We analyzed 1,055 patients diagnosed with stage I-III breast cancer between 1990 and 1996. Variables studied included socioeconomic factors, tumor characteristics, concurrent medical conditions, and treatment. The primary end point was recurrence-free survival (RFS). Multivariable analyses were performed using recursive partitioning and Cox proportional hazards regression. RESULTS: The most significant difference in prognosis was between patients with fewer than four and those with at least four positive nodes (P <.0001). Four distinct prognostic groups (5-year RFS, 97%, 78%, 58%, and 27%) were developed, defined by the number of positive nodes, tumor size, progesterone receptor (PR) status, differentiation, race, and marital status. Patients with fewer than four positive nodes and tumor < or = 2 cm, PR positive, and well or moderately differentiated had the best prognosis. RFS in this group was unaffected by type of adjuvant therapy (P =.38). Patients with at least four positive nodes and PR-negative tumors had the worst prognosis, and those treated with tamoxifen plus chemotherapy had the best outcome in this group (P =.0001). Among patients in the two intermediate-risk groups, those treated with tamoxifen or a combination of tamoxifen and chemotherapy had the best outcome. CONCLUSION: Lymph node status, PR status, tumor size, differentiation, race, and marital status are valuable for prognostication in breast cancer. The prognostic groups derived can provide guidance for clinical trial design, patient management, and future treatment policy.     

Adjuvant cyclophosphamide, methotrexate, and fluorouracil in patients with axillary node-positive breast cancer: an update of the Guy's/Manchester trial

Between 1976 and 1985, 391 patients (202 premenopausal, 189 postmenopausal) with operable breast cancer and positive axillary lymph nodes were randomized after total mastectomy and axillary clearance to receive cyclophosphamide, methotrexate, and fluorouracil (CMF) (n = 193) or no adjuvant therapy (n = 198). After a median follow-up of 8 years, both relapse-free survival (RFS) and survival (S) were significantly prolonged in premenopausal patients receiving CMF (RFS, P less than .001; S, P = .003). Treatment with CMF resulted in a significant improvement in RFS in premenopausal patients both with steroid receptor-positive and steroid receptor-negative tumors and also in subgroups of premenopausal patients defined by the number of axillary nodes involved. Premenopausal patients who developed permanent amenorrhea following CMF had a significantly better RFS than those who continued to menstruate. Induction of amenorrhea following CMF was related to age, with almost all patients over 40 years becoming amenorrheic. For patients less than or equal to 40 years, development of amenorrhea following CMF did not influence outcome. No difference was detected between control and CMF groups (RFS, P = .9; S, P = .9) in postmenopausal patients nor in any subgroup of these patients. The results of this trial of the efficacy of CMF for improving RFS and S have strengthened with longer follow-up.     

Chemoendocrine therapy for premenopausal women with axillary lymph node-positive, steroid hormone receptor-positive breast cancer: results from INT 0101 (E5188).

PURPOSE: Chemotherapy, tamoxifen, and ovarian ablation/suppression (OA/OS) are effective adjuvant approaches for premenopausal, steroid hormone receptor-positive breast cancer. The value of combined therapy has not been clearly established. PATIENTS AND METHODS: Premenopausal women with axillary lymph node-positive, steroid hormone receptor-positive breast cancer (1,503 eligible patients) were randomly assigned to six cycles of cyclophosphamide, doxorubicin, and fluorouracil (CAF), CAF followed by 5 years of monthly goserelin (CAF-Z), or CAF followed by 5 years of monthly goserelin and daily tamoxifen (CAF-ZT). The primary end points were time to recurrence (TTR), disease-free survival (DFS), and overall survival (OS) for CAF-Z versus CAF, and CAF-ZT versus CAF-Z. RESULTS: With a median follow-up of 9.6 years, the addition of tamoxifen to CAF-Z improved TTR and DFS but not OS. There was no overall advantage for addition of goserelin to CAF. CONCLUSION: Addition of tamoxifen to CAF-Z improves outcome for premenopausal node-positive, receptor-positive breast cancer. The role of OA/OS alone or with other endocrine agents should be studied more intensely.     

The effect of oestrogen and progesterone receptors on recurrence and survival in patients with carcinoma of the breast

Recurrence and survival rates were studied in 175 women with breast cancer who, until the development of recurrent disease, received no treatment other than a modified radical (Patey) mastectomy, and in whom the oestrogen (REc) and progesterone (RPc) receptor content of the primary tumour was measured. At the time of first relapse most patients received endocrine therapy. At a minimum follow-up of 58 months post menopausal patients who possessed REc had an increased relapse-free survival (RFS) (P = 0.02). When examined by node status patients with 1-3 axillary nodes containing tumour also had an improvement in RFS (P = 0.02). There was no benefit for node-negative or premenopausal patients. In 163 patients in whom RPc was measured, RFS was unaffected by the possession of this receptor regardless of the degree of node involvement or menopausal status. Patients with REc had a significantly longer survival following mastectomy than patients without it (P = 0.006). This was most marked in post-menopausal (P = 0.003) and node-positive (P = 0.03) patients. Survival following mastectomy was also increased in patients possessing RPc (P = 0.04) and again was most marked for post-menopausal patients (P = 0.01), although no difference could be identified within node subgroups. There were significant differences in the post-relapse survival of REc and RPc positive and negative patients (REc P = 0.03, RPc P = 0.001). Patients with both receptors survived approximately 37 months longer than their receptor-negative counterparts. This study failed to confirm that the measurement of REc and RPc can reliably predict early relapse in breast cancer. The greater overall survival of receptor-positive patients is mainly due to an increase in survival following relapse. This may reflect the response of receptor-positive tumours to endocrine therapy given for recurrent disease.