A. U. Buzdar

Anastrozole alone or in combination with tamoxifen versus tamoxifen alone for adjuvant treatment of postmenopausal women with early breast cancer: first results of the ATAC randomised trial.

BACKGROUNDnIn the adjuvant setting, tamoxifen is the established treatment for postmenopausal women with hormone-sensitive breast cancer. However, it is associated with several side-effects including endometrial cancer and thromboembolic disorders. We aimed to compare the safety and efficacy outcomes of tamoxifen with those of anastrozole alone and the combination of anastrozole plus tamoxifen for 5 years.nnnMETHODSnParticipants were postmenopausal patients with invasive operable breast cancer who had completed primary therapy and were eligible to receive adjuvant hormonal therapy. The primary endpoints were disease-free survival and occurrence of adverse events. Analysis for efficacy was by intention to treat.nnnFINDINGSn9366 patients were recruited, of whom 3125 were randomly assigned anastrozole, 3116 tamoxifen, and 3125 combination. Median follow-up was 33.3 months. 7839 (84%) patients were known to be hormone-receptor-positive. Disease-free survival at 3 years was 89.4% on anastrozole and 87.4% on tamoxifen (hazard ratio 0.83 [95% CI 0.71-0.96], p=0.013). Results with the combination were not significantly different from those with tamoxifen alone (87.2%, 1.02 [0.89-1.18], p=0.8). The improvement in disease-free survival with anastrozole was seen in the subgroup of hormone-receptor-positive patients, but not the receptor-negative patients. Incidence of contralateral breast cancer was significantly lower with anastrozole than with tamoxifen (odds ratio 0.42 [0.22-0.79], p=0.007). Anastrozole was significantly better tolerated than tamoxifen with respect to endometrial cancer (p=0.02), vaginal bleeding and discharge (p<0.0001 for both), cerebrovascular events (p=0.0006), venous thromboembolic events (p=0.0006), and hot flushes (p<0.0001). Tamoxifen was significantly better tolerated than anastrozole with respect to musculoskeletal disorders and fractures (p<0.0001 for both).nnnINTERPRETATIONnAnastrozole is an effective and well tolerated endocrine option for the treatment of postmenopausal patients with hormone-sensitive early breast cancer. Longer follow-up is required before a final benefit:risk assessment can be made.

Effect of anastrozole and tamoxifen as adjuvant treatment for early-stage breast cancer: 10-year analysis of the ATAC trial

BACKGROUNDnThe Arimidex, Tamoxifen, Alone or in Combination (ATAC) trial was designed to compare the efficacy and safety of anastrozole (1 mg) with tamoxifen (20 mg), both given orally every day for 5 years, as adjuvant treatment for postmenopausal women with early-stage breast cancer. In this analysis, we assess the long-term outcomes after a median follow-up of 120 months.nnnMETHODSnWe used a proportional hazards model to assess the primary endpoint of disease-free survival, and the secondary endpoints of time to recurrence, time to distant recurrence, incidence of new contralateral breast cancer, overall survival, and death with or without recurrence in all randomised patients (anastrozole n=3125, tamoxifen n=3116) and hormone-receptor-positive patients (anastrozole n=2618, tamoxifen n=2598). After treatment completion, we continued to collect data on fractures and serious adverse events in a masked fashion (safety population: anastrozole n=3092, tamoxifen n=3094). This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN18233230.nnnFINDINGSnPatients were followed up for a median of 120 months (range 0-145); there were 24,522 woman-years of follow-up in the anastrozole group and 23,950 woman-years in the tamoxifen group. In the full study population, there were significant improvements in the anastrozole group compared with the tamoxifen group for disease-free survival (hazard ratio [HR] 0·91, 95% CI 0·83-0·99; p=0·04), time to recurrence (0·84, 0·75-0·93; p=0·001), and time to distant recurrence (0·87, 0·77-0·99; p=0·03). For hormone-receptor-positive patients, the results were also significantly in favour of the anastrozole group for disease-free survival (HR 0·86, 95% CI 0·78-0·95; p=0·003), time to recurrence (0·79, 0·70-0·89; p=0·0002), and time to distant recurrence (0·85, 0·73-0·98; p=0·02). In hormone-receptor-positive patients, absolute differences in time to recurrence between anastrozole and tamoxifen increased over time (2·7% at 5 years and 4·3% at 10 years) and recurrence rates remained significantly lower on anastrozole than tamoxifen after treatment completion (HR 0·81, 95% CI 0·67-0·98; p=0·03), although the carryover benefit was smaller after 8 years. There was weak evidence of fewer deaths after recurrence with anastrozole compared with tamoxifen treatment in the hormone-receptor-positive subgroup (HR 0·87, 95% CI 0·74-1·02; p=0·09), but there was little difference in overall mortality (0·95, 95% CI 0·84-1·06; p=0·4). Fractures were more frequent during active treatment in patients receiving anastrozole than those receiving tamoxifen (451 vs 351; OR 1·33, 95% CI 1·15-1·55; p<0·0001), but were similar in the post-treatment follow-up period (110 vs 112; OR 0·98, 95% CI 0·74-1·30; p=0·9). Treatment-related serious adverse events were less common in the anastrozole group than the tamoxifen group (223 anastrozole vs 369 tamoxifen; OR 0·57, 95% CI 0·48-0·69; p<0·0001), but were similar after treatment completion (66 vs 78; OR 0·84, 95% CI 0·60-1·19; p=0·3). No differences in non-breast cancer causes of death were apparent and the incidence of other cancers was similar between groups (425 vs 431) and continue to be higher with anastrozole for colorectal (66 vs 44) and lung cancer (51 vs 34), and lower for endometrial cancer (six vs 24), melanoma (eight vs 19), and ovarian cancer (17 vs 28). No new safety concerns were reported.nnnINTERPRETATIONnThese data confirm the long-term superior efficacy and safety of anastrozole over tamoxifen as initial adjuvant therapy for postmenopausal women with hormone-sensitive early breast cancer.

Anastrozole alone or in combination with tamoxifen versus tamoxifen alone for adjuvant treatment of postmenopausal women with early-stage breast cancer: results of the ATAC (Arimidex, Tamoxifen Alone or in Combination) trial efficacy and safety update analyses.

The first analysis of the ATAC (Arimidex, Tamoxifen Alone or in Combination) trial (median follow‐up, 33 months) demonstrated that in adjuvant endocrine therapy for postmenopausal patients with early‐stage breast cancer, anastrozole was superior to tamoxifen in terms of disease‐free survival (DFS), time to recurrence (TTR), and incidence of contralateral breast cancer (CLBC). In the current article, the results of the first efficacy update, based on a median follow‐up period of 47 months, are reported along with the results of an updated safety analysis, performed 7 months after the first analysis (median duration of treatment, 36.9 months).

Long-term follow-up of patients with complete remission following combination chemotherapy for metastatic breast cancer

PURPOSEnTo determine the long-term clinical course of patients with metastatic breast cancer (MBC) who achieved a complete remission with doxorubicin-alkylating agent-containing combination chemotherapy programs.nnnPATIENTS AND METHODSnTo assess the long-term prognosis of MBC, we reviewed our experience with 1,581 patients treated on consecutive doxorubicin and alkylating agent-containing front-line treatment protocols between 1973 and 1982. Treatment was administered for a maximum duration of 2 years. Characteristics of long-term survivors were evaluated, and hazard rates for progression were calculated.nnnRESULTSnFrom this group, 263 (16.6%) achieved complete responses (CR) and 49 (3.1%) remained in CR for more than 5 years. After a median duration of 191 months, 26 patients remain in first CR, four patients died in CR at times ranging from 118 to 234 months, 18 patients died of breast cancer, and one is alive with metastatic disease. Compared with the overall CR and total patient populations, the long-term CR group had more premenopausal patients, a younger median age, a lower tumor burden, and better performance status. The hazard function shows a substantial drop in risk of progression after approximately 3 years from initiation of therapy. Ten long-term CR patients developed second primary cancers: breast (3), ovary (2), pancreas (1), endometrium (1), colon (1), head and neck (1), and lung (1).nnnCONCLUSIONnMost patients with MBC treated with systemic therapies have only temporary responses to treatment, but some patients continue in CR following initial treatment. These data show that a small percentage of patients achieve long-term remissions with standard chemotherapy regimens. Remission consolidation strategies are needed.

Management of stage III primary breast cancer with primary chemotherapy, surgery, and radiation therapy

One hundred seventy‐four evaluable patients with noninflammatory Stage III (both operable and inoperable) breast cancer were treated with a combined modality strategy between 1974 and 1985. All patients received combination chemotherapy with 5‐fluorouracil, Adriamycin (doxorubicin), and cyclophosphamide (FAC) as their initial form of therapy. After three cycles of chemotherapy, local treatment in the form of a total mastectomy with axillary dissection, or radiotherapy, or both, was completed. Subsequently, adjuvant chemotherapy was continued. There were 48 patients with Stage IIIA, and 126 patients with Stage IIIB disease. A complete remission was achieved in 16.7% of the patients, and 70.7% achieved a partial remission after the initial three cycles of FAC. The complete response rate was higher for patients with Stage IIIA, than for patients with Stage IIIB disease. All but six of the 174 patients treated were rendered disease‐free after induction chemotherapy and local treatment. The median follow‐up of this group of patients is 59 months. The 5‐year disease‐free survival rates were 84% for patients with Stage IIIA, and 33% for patients with Stage IIIB disease. The 5‐year survival rate for, patients with Stage IIIA was 84%, and for patients with Stage IIIB 44%. At 10 years, 56% of patients with Stage IIIA and 26% of patients with Stage IIIB disease are projected to be alive. Younger patients, and those with estrogen receptor‐positive tumors, had a trend for better survival than older patients and those with estrogen receptor‐negative tumors. The quality of response to induction chemotherapy correlated prominently with prognosis, as did compliance with treatment. Twenty‐six patients (15.3%) had locoregional recurrence. This multidisciplinary approach to locally advanced breast cancer rendered most patients disease‐free and produced an excellent local control rate. Modifications of this treatment strategy may result in further improvement of survival rates.

Comprehensive side-effect profile of anastrozole and tamoxifen as adjuvant treatment for early-stage breast cancer: long-term safety analysis of the ATAC trial

BACKGROUNDnThe Arimidex (anastrozole), Tamoxifen, Alone or in Combination (ATAC) trial was designed to compare the efficacy and safety of anastrozole with tamoxifen as adjuvant treatment for postmenopausal women with early-stage breast cancer. After an extended follow-up beyond the 5 years of treatment, we aimed to assess the safety, tolerability, and risk-benefit indices of these compounds.nnnMETHODSnWe analysed postmenopausal women (mean age 64 years [SD 9]) with localised breast cancer randomly assigned to anastrozole (n=3125) or tamoxifen (n=3116). Efficacy measures, including death and risk-benefit indices, were analysed by intention to treat. Safety analyses were based on treatment first received (n=3092 for anastrozole and n=3094 tamoxifen). We calculated a risk-benefit analysis using the two global indices for the Womens Health Initiative and for Disease-Free Survival and Serious Adverse Events. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN18233230.nnnFINDINGSnAt median follow-up of 68 months (range 1-93), treatment-related adverse events occurred significantly less often with anastrozole than with tamoxifen (1884 [61%] vs 2117 [68%]; p<0.0001), as did treatment-related serious adverse events (146 [5%] vs 277 [9%]; p<0.0001) and adverse events leading to withdrawal (344 [11%] vs 442 [14%]; p=0.0002). Patients given anastrozole had significantly fewer overall events for the Global Index of the Womens Health Initiative (744 [24%] vs 851 [27%]; hazard ratio 0.85 [95% CI 0.77-0.94], p=0.001) and the Global Index of Disease-Free Survival and Serious Adverse Events (1453 [46%] vs 1594 [51%]; 0.88 [0.82-0.94]; p=0.0004).nnnINTERPRETATIONnAnastrozole is tolerated better than tamoxifen by postmenopausal women with early-stage breast cancer, and results in fewer serious adverse events. Furthermore, it has a more favourable overall risk-benefit profile and lower recurrence rate than tamoxifen.

Multimodal treatment of locoregionally advanced breast cancer

Fifty‐two patients with locally advanced primary breast cancer (T3, T4/N2, N3) without distant metastases were treated with three cycles of combination chemotherapy consisting of 5‐FU, Adriamycin and cyclophosphamide (FAC) and immunotherapy with Bacillus Calmette‐Guerin (BCG) followed by local therapy (simple mastectomy and/or radiotherapy to breast/chest wall and regional lymphatics) and adjuvant chemotherapy to complete two years of treatment. Forty‐nine of 52 (94%) patients were rendered free of clinically detectable disease. The median disease‐free interval was 24 months. At a median follow‐up time of 60 months, 40% of patients remained free of disease, off all therapy. Those patients who completed two years of therapy and started adjuvant chemotherapy promptly after local treatment had a 48% disease‐free survival at five years. Local recurrences were observed in 21% of patients. Distant metastases developed in 40% of patients. Despite good tolerance, treatment compliance was poor. The complete remission rate with this multimodal approach is high and long‐term disease‐free survival is achieved in a considerable number of patients.

Decreased cardiac toxicity of doxorubicin administered by continuous intravenous infusion in combination chemotherapy for metastatic breast carcinoma

Two hundred and seventy‐four consecutive patients with measurable metastatic breast cancer, without prior exposure to cytotoxic agents were treated with tamoxifen, 5‐fluorouracil, doxorubicin, and cyclophosphamide (FAC). The initial 133 patients received doxorubicin by bolus IV administration and for the next group of 141 patients doxorubicin was administered via a central venous catheter over a 48‐hour (79 patients) or 96‐hour (62 patients) continuous infusion schedule. Patients treated with bolus doxorubicin had this agent discontinued usually when 450 mg/m2 were reached; for patients in the infusion group treatment was continued until evidence of progressive disease or clinical or subclinial cardiac dysfunction developed. The complete remission rate was 21% the partial remission rate, 59%. There were no differences in response rate, response duration, or survival duration between groups of patients treated with doxorubicin by bolus, 48‐hour or 96‐hour infusion FAC. The incidence of moderate and severe nausea and vomiting was lower in the group of patients treated with infusion FAC as compared to bolus FAC (P < 0.001); however, the incidence of mucositis was higher in the infusion group than in the bolus group (P < 0.001). Doxorubicin administered by continuous infusion schedules was less cardiotoxic than when administered by bolus, as shown by a >75% decrease in the frequency of clinical congestive heart failure at cumulative dosages ≥ 450 mg/m2 (P = 0.004). Doxorubicin administered as a 48‐hour or 96‐hour continuous IV infusion is safer, and better tolerated than doxorubicin administered by bolus.

Risk factors for joint symptoms in patients enrolled in the ATAC trial: a retrospective, exploratory analysis

BACKGROUNDnJoint symptoms (eg, arthralgia and arthritis) are a well-known side-effect of aromatase inhibitors. Low oestrogen concentrations and postmenopausal status are associated with the development of these symptoms. Chemotherapy can also induce joint symptoms, but tamoxifen seems to have little effect on their incidence. The aim of this study was to assess the relative importance of different risk factors for treatment-emergent joint symptoms in patients assigned to anastrozole or tamoxifen as adjuvant treatment for postmenopausal breast cancer.nnnMETHODSnThe Arimidex Tamoxifen Alone or in Combination (ATAC) trial randomly assigned 9366 postmenopausal women to anastrozole (1 mg/day), to tamoxifen (20 mg/day), or to a combination of both. Our analyses were based on data from case reports of 5433 women who were randomly assigned to anastrozole or tamoxifen, who started with their allocated treatment, and who did not have joint symptoms at entry (anastrozole group: n=2698; tamoxifen group: n=2735). The analysis was restricted to the occurrence of joint symptoms at any time during active treatment or within 14 days of its discontinuation. Joint symptoms were defined as any report of arthralgia, arthrosis, arthritis, or joint disorder on a case-report form. Joint disorders were defined as reports of cervical spondylosis, osteoarthritis, and disc herniation. The date of occurrence was recorded, along with a severity score (ie, mild, moderate, or severe). Our analyses were done by use of logistic regression. The ATAC trial is registered as an International Standard Randomised Controlled Trial, number ISRCTN18233230.nnnFINDINGSn777 of 1914 women (40.6%) who used hormone replacement therapy (HRT) before trial entry developed joint symptoms compared with 1001 of 3519 women (28.4%) without previous HRT use (odds ratio [OR] 1.72 [95% CI 1.53-1.93]). Women with hormone-receptor-negative breast cancer developed significantly fewer joint symptoms compared with those with hormone-receptor-positive tumours (124 of 461 [26.9%] vs 1556 of 4548 [34.2%]; OR 0.71 [0.57-0.88]). Women for whom chemotherapy was part of their initial treatment developed significantly more joint symptoms than those who did not receive it (461 of 1219 women [37.8%] vs 1317 of 4214 women [31.3%]; OR 1.34 [1.17-1.53]). Obese women (body-mass index [BMI] >30 kg/m(2)) reported more joint symptoms than women with a BMI of 25-30 kg/m(2) or those with a BMI <25 kg/m(2) (504 of 1354 women [37.2%] vs 502 of 1926 women [31.3%; OR 1.01 (0.88-1.16)] vs 592 of 1908 women [31.0%; OR 1.32 (1.14-1.53)]) and women on anastrozole reported more joint symptoms compared with those on tamoxifen (949 of 2698 women [35.2%] vs 829 of 2735 women [30.3%]; OR 1.25 [1.11-1.40]). All significant risk factors from the univariate analysis were included in a multivariate analysis and remained significant with little change.nnnINTERPRETATIONnIn this trial, the major risk factors for developing joint symptoms were previous HRT, hormone-receptor positivity, previous chemotherapy, obesity, and treatment with anastrozole. Discussion of identified risk factors is appropriate when counselling women before initiation of adjuvant hormonal treatment.

Multivariate Analysis of Prognostic Factors in Metastatic Breast Cancer

Univariate and multivariate analyses were conducted on data collected from the records of 619 patients with metastatic breast cancer in whom an Adriamycin-containing chemotherapeutic regimen was used. Using a forward, stepwise logistic regression procedure, several models or equations in which a small number of pretreatment factors were incorporated were generated and the probability of response to therapy was accurately predicted. The predictive ability of these models was tested retrospectively in 546 of the 619 patients from whom the data were derived and prospectively in a new population of 200 patients with metastatic breast cancer also treated with a therapeutically equivalent Adriamycin combination. Using similar univariate techniques, pretreatment factors were correlated with the length of survival after therapy. The proportional hazard model of Cox was used to develop a regression model relating survival to pretreatment characteristics in much the same manner as that of the response model. The total population of the initial group of patients was divided according to four levels of hazard ratio, and survival distributions were compared. This model also was tested progressively and its predictive capability was confirmed. The prediction of individual outcome is a valuable capability in the comparison of clinical trials and the continuing evaluation of biologic changes in patients with metastatic carcinoma; such a method is described in this paper.