Marc Debled

Randomized Phase II Trial of Everolimus in Combination With Tamoxifen in Patients With Hormone Receptor–Positive, Human Epidermal Growth Factor Receptor 2–Negative Metastatic Breast Cancer With Prior Exposure to Aromatase Inhibitors: A GINECO Study

PURPOSE Cross-talk between signal transduction pathways likely contributes to hormone resistance in metastatic breast cancer (mBC). Everolimus, an oral inhibitor of the mammalian target of rapamycin, has restored sensitivity in endocrine-resistance models and shown anticancer activity in early-phase mBC clinical trials. This analysis evaluated efficacy and safety of everolimus in combination with tamoxifen in patients with mBC resistant to aromatase inhibitors (AIs). PATIENTS AND METHODS This open-label, phase II study randomly assigned postmenopausal women with hormone receptor-positive, human epidermal growth factor receptor 2-negative, AI-resistant mBC to tamoxifen 20 mg/d plus everolimus 10 mg/d (n = 54) or tamoxifen 20 mg/d alone (n = 57). Randomization was stratified by primary and secondary hormone resistance. Primary end point was clinical benefit rate (CBR), defined as the percentage of all patients with a complete or partial response or stable disease at 6 months. No formal statistical comparison between groups was planned. RESULTS The 6-month CBR was 61% (95% CI, 47 to 74) with tamoxifen plus everolimus and 42% (95% CI, 29 to 56) with tamoxifen alone. Time to progression (TTP) increased from 4.5 months with tamoxifen alone to 8.6 months with tamoxifen plus everolimus, corresponding to a 46% reduction in risk of progression with the combination (hazard ratio [HR], 0.54; 95% CI, 0.36 to 0.81). Risk of death was reduced by 55% with tamoxifen plus everolimus versus tamoxifen alone (HR, 0.45; 95% CI, 0.24 to 0.81). The main toxicities associated with tamoxifen plus everolimus were fatigue (72% v 53% with tamoxifen alone), stomatitis (56% v 7%), rash (44% v 7%), anorexia (43% v 18%), and diarrhea (39% v 11%). CONCLUSION This study suggests that tamoxifen plus everolimus increased CBR, TTP, and overall survival compared with tamoxifen alone in postmenopausal women with AI-resistant mBC.

Neoadjuvant chemotherapy for operable breast carcinoma larger than 3 cm: A unicentre randomized trial with a 124-month median follow-up

BACKGROUND Neoadjuvant chemotherapy improves overall survival and renders possible breast-conserving treatment in locally advanced breast cancer. It was necessary for this method to be evaluated in operable breast tumors too large to be treated immediately by conserving surgery. Initial results of this randomized trial were published in Annals of Oncology (1991). PATIENTS AND METHODS Women with T2 > 3 cm or T3 N0-1 M0 breast tumors were treated by either initial mastectomy followed by adjuvant chemotherapy, or neoadjuvant chemotherapy followed by adjusted locoregional treatment. Chemotherapy was the same in the two arms. The prognostic and predictive factors of response to chemotherapy were analyzed. RESULTS Conserving treatments were performed in 63% at the end of neoadjuvant chemotherapy and this rate had decreased to 45% at the median follow-up of 124 months. Survivals are identical in the two treatment groups. Initial clinical tumor size < 40 mm, IHC-ER < 10% and Mib1 > 40% are predictive of tumor response to chemotherapy by uni- and multivariate analyses. For outcome prediction, c-erb-B2 > 0% is the independent prognostic factor for overall and metastasis-free survivals. CONCLUSION Breast-conserving therapy can be performed in more than half of all cases without alteration of survival, despite a non-negligible rate of local recurrences.

CYP2D6 Genotype and Tamoxifen Response in Postmenopausal Women with Endocrine-Responsive Breast Cancer: The Breast International Group 1-98 Trial

BACKGROUND Adjuvant tamoxifen therapy is effective for postmenopausal women with endocrine-responsive breast cancer. Cytochrome P450 2D6 (CYP2D6) enzyme metabolizes tamoxifen to clinically active metabolites, and CYP2D6 polymorphisms may adversely affect tamoxifen efficacy. In this study, we investigated the clinical relevance of CYP2D6 polymorphisms. METHODS We obtained tumor tissues and isolated DNA from 4861 of 8010 postmenopausal women with hormone receptor-positive breast cancer who enrolled in the randomized, phase III double-blind Breast International Group (BIG) 1-98 trial between March 1998 and May 2003 and received tamoxifen and/or letrozole treatment. Extracted DNA was used for genotyping nine CYP2D6 single-nucleotide polymorphisms using polymerase chain reaction-based methods. Genotype combinations were used to categorize CYP2D6 metabolism phenotypes as poor, intermediate, and extensive metabolizers (PM, IM, and EM, respectively; n = 4393 patients). Associations of CYP2D6 metabolism phenotypes with breast cancer-free interval (referred to as recurrence) and treatment-induced hot flushes according to randomized endocrine treatment and previous chemotherapy were assessed. Cox proportional hazards models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs). All statistical tests were two-sided. RESULTS No association between CYP2D6 metabolism phenotypes and breast cancer-free interval was observed among patients who received tamoxifen monotherapy without previous chemotherapy (P = .35). PM or IM phenotype had a non-statistically significantly reduced risk of breast cancer recurrence compared with EM phenotype (PM or IM vs EM, HR of recurrence = 0.86, 95% CI = 0.60 to 1.24). CYP2D6 metabolism phenotype was associated with tamoxifen-induced hot flushes (P = .020). Both PM and IM phenotypes had an increased risk of tamoxifen-induced hot flushes compared with EM phenotype (PM vs EM, HR of hot flushes = 1.24, 95% CI = 0.96 to 1.59; IM vs EM, HR of hot flushes = 1.23, 95% CI = 1.05 to 1.43). CONCLUSIONS CYP2D6 phenotypes of reduced enzyme activity were not associated with worse disease control but were associated with increased hot flushes, contrary to the hypothesis. The results of this study do not support using the presence or absence of hot flushes or the pharmacogenetic testing of CYP2D6 to determine whether to treat postmenopausal breast cancer patients with tamoxifen.

6 months versus 12 months of adjuvant trastuzumab for patients with HER2-positive early breast cancer (PHARE): a randomised phase 3 trial

BACKGROUND Since 2005, 12 months of adjuvant trastuzumab has been the standard treatment for patients with HER2-positive early-stage breast cancer. However, the optimum duration of treatment has been debated. We did a non-inferiority trial of a shorter exposure of 6 months versus the standard 12 months of trastuzumab for patients with early breast cancer. METHODS We did an open-label, randomised, phase 3 trial in 156 centres in France. Patients with HER2-positive early breast cancer who had received at least four cycles of chemotherapy, had breast-axillary surgery, and had received up to 6 months of trastuzumab (administered by intravenous infusions over 30-90 min every 3 weeks; initial loading dose 8 mg/kg; 6 mg/kg thereafter) before randomisation were eligible. Patients were randomly assigned via central randomisation procedure with web-based software to continue trastuzumab for another 6 months (12 months total duration; control group) or to discontinue trastuzumab at 6 months (6 months total duration; experimental group). Randomisation was stratified by concomitant or sequential administration of trastuzumab with chemotherapy, oestrogen-receptor status, and centre using a minimisation algorithm. The primary endpoint was disease-free survival, with a prespecified non-inferiority margin of 1·15. Analyses were done in the intention-to-treat population. This study is registered at ClinicalTrials.gov, number NCT00381901. FINDINGS 1691 patients were randomly assigned to receive 12 months of trastuzumab and 1693 to receive 6 months of trastuzumab; 1690 patients in each group were included in the intention-to-treat analyses. After a median follow-up of 42·5 months (IQR 30·1-51·6), 175 disease-free survival events were noted in the 12-month group and 219 in the 6-month group. 2-year disease-free survival was 93·8% (95% CI 92·6-94·9) in the 12-month group and 91·1% (89·7-92·4) in the 6-month group (hazard ratio 1·28, 95% CI 1·05-1·56; p=0·29). 119 (93%) of the 128 cardiac events (clinical or based on assessment of left ventricular ejection fraction) occurred while patients were receiving trastuzumab. Significantly more patients in the 12-month group experienced a cardiac event than did those in the 6-month group (96 [5·7%] of 1690 patients vs 32 [1·9%] of 1690 patients, p<0·0001). INTERPRETATION After 3·5 years follow-up, we failed to show that 6 months of treatment with trastuzumab was non-inferior to 12 months of trastuzumab. Despite the higher rates of cardiac events, 12 months of adjuvant trastuzmab should remain the standard of care. FUNDING French National Cancer Institute.

Variables with time-varying effects and the Cox model: Some statistical concepts illustrated with a prognostic factor study in breast cancer

BackgroundThe Cox model relies on the proportional hazards (PH) assumption, implying that the factors investigated have a constant impact on the hazard - or risk - over time. We emphasize the importance of this assumption and the misleading conclusions that can be inferred if it is violated; this is particularly essential in the presence of long follow-ups.MethodsWe illustrate our discussion by analyzing prognostic factors of metastases in 979 women treated for breast cancer with surgery. Age, tumour size and grade, lymph node involvement, peritumoral vascular invasion (PVI), status of hormone receptors (HRec), Her2, and Mib1 were considered.ResultsMedian follow-up was 14 years; 264 women developed metastases. The conventional Cox model suggested that all factors but HRec, Her2, and Mib1 status were strong prognostic factors of metastases. Additional tests indicated that the PH assumption was not satisfied for some variables of the model. Tumour grade had a significant time-varying effect, but although its effect diminished over time, it remained strong. Interestingly, while the conventional Cox model did not show any significant effect of the HRec status, tests provided strong evidence that this variable had a non-constant effect over time. Negative HRec status increased the risk of metastases early but became protective thereafter. This reversal of effect may explain non-significant hazard ratios provided by previous conventional Cox analyses in studies with long follow-ups.ConclusionsInvestigating time-varying effects should be an integral part of Cox survival analyses. Detecting and accounting for time-varying effects provide insights on some specific time patterns, and on valuable biological information that could be missed otherwise.

Abstract S1-6: TAMRAD: A GINECO Randomized Phase II Trial of Everolimus in Combination with Tamoxifen Versus Tamoxifen Alone in Patients (pts) with Hormone-Receptor Positive, HER2 Negative Metastatic Breast Cancer (MBC) with Prior Exposure to Aromatase Inhibitors (AI).

Background: Resistance to hormonal therapy may be associated with activation of the PI3K/AKT pathway. Preclinically, everolimus (RAD), an oral inhibitor of mTOR, has been shown to reverse resistance to tamoxifen (TAM). In a prior randomized phase II trial in estrogen-receptor positive operable breast cancer pts, RAD significantly increased neoadjuvant AI (letrozole) efficacy when given in combination. The objective of this randomized phase II study was to estimate the efficacy of the RAD+TAM combination in AI pretreated hormone-receptor positive/HER2 negative MBC pts based on the assumption that prior exposure to an AI might potentially enrich the proportion of pts whose tumor may be driven by an activation of the PI3K/AKT/mTOR pathway. Methods: Eligible patients were stratified by time to progression after prior AI treatment and randomized 1:1 to receive either TAM (20mg/day) alone or RAD+TAM (RAD: 10 mg/d; TAM: 20mg/d). The primary objective was to estimate clinical benefit rate (CB) defined as the absence of progression at 6 months in the RAD+TAM arm. Using a Simon two-stage Minimax design, with alpha=5% and power=90%, considering a gain in CB of 20% as the minimum needed to warrant further study for the combination and assuming a CB of 50% in the TAM arm, 53 evaluable patients were needed in both arms. Secondary endpoints included safety and time to progression (TTP). Results: In total, 111 pts (TAM: 57, RAD+TAM: 54) were randomized. Baseline characteristics were well balanced between the two treatment arms; median age was 64 years (range, 41-86); most pts were PS 0 (55 pts, 51%) or PS 1 (46 pts, 43%) Prior AI treatment had been given to 34 pts (31%) in the adjuvant setting; to 67 pts (60%) in the metastatic setting and 10 pts (9%) in both the adjuvant and metastatic setting. This population was poorly hormone sensitive as all but 10 pts (9%) had progressed either during AI or within 6 months after adjuvant AI. Furthermore, 57 pts (51%) and 28 pts (25%) had received prior chemotherapy in the adjuvant and/or metastatic setting, respectively. Efficacy: In an intent-to-treat analysis with a median follow-up of 13 months, CB was 42.1% (95% CI, 29.1-55.9) in the TAM arm and 61.1% (95% CI, 46.9-74.1) in the RAD+TAM arm. Median TTP was 4.5 months (95% CI, 3.7-8.7) with TAM and 8.5 months (95% CI, 6.01-13.9) with RAD+TAM (log-rank test: p=0.008, exploratory analysis). At the time of analysis, 17 pts had died in the TAM arm and 5 patients had died in the RAD+TAM arm (there was no toxic death). Safety: Safety data showed that toxicity was manageable in both groups. RAD had to be decreased to 5 mg/day for 15 pts (28%); 3 and 2 pts had to stop the treatment due to toxicities in the TAM and RAD+TAM arms respectively. Severe adverse events (G3-4) >10% were stomatitis (0/11%, TAM/RAD+TAM) and pain (19%/7%). Conclusions: RAD combined with tamoxifen provides significant improvement in the 6 months clinical benefit rate compared to tamoxifen alone. Based on these promising results, this combination warrants further study in hormone-receptor positive/HER2 negative MBC after progression on AI. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr S1-6.

Relative Effectiveness of Letrozole Compared With Tamoxifen for Patients With Lobular Carcinoma in the BIG 1-98 Trial

PURPOSE To evaluate the relative effectiveness of letrozole compared with tamoxifen for patients with invasive ductal or lobular carcinoma. PATIENTS AND METHODS Patients diagnosed with early-stage invasive ductal carcinoma (IDC) or classic invasive lobular carcinoma (ILC) who were randomly assigned onto the Breast International Group (BIG) 1-98 trial and who had centrally reviewed pathology data were included (N = 2,923). HER2-negative IDC and ILC were additionally classified as hormone receptor-positive with high (luminal B [LB] -like) or low (luminal A [LA] -like) proliferative activity by Ki-67 labeling index. Survival analyses were performed with weighted Cox models that used inverse probability of censoring weighted modeling. RESULTS The median follow-up time was 8.1 years. In multivariable models for disease-free survival (DFS), significant interactions between treatment and histology (ILC or IDC; P = .006) and treatment and subgroup (LB like or LA like; P = .01) were observed. In the ILC subset, there was a 66% reduction in the hazard of a DFS event with letrozole for LB (hazard ratio [HR], 0.34; 95% CI, 0.21 to 0.55) and a 50% reduction for LA subtypes (HR, 0.50; 95% CI, 0.32 to 0.78). In the IDC subset, there was a significant 35% reduction in the hazard of a DFS event with letrozole for the LB subtype (HR, 0.65; 95% CI, 0.53 to 0.79), but no difference between treatments was noted for IDC and the LA subtype (HR, 0.95; 95% CI, 0.76 to 1.20). CONCLUSION The magnitude of benefit of adjuvant letrozole is greater for patients diagnosed with lobular carcinoma versus ductal carcinoma.

Distinction between isolated tumor cells and micrometastases in breast cancer: is it reliable and useful?

In routine practice, the distinction between isolated tumor cells (ITC) and micrometastases (MIC) in patients with breast cancer is sometimes difficult to discern. The authors assessed differences in classifying patients according to the American Joint Commission on Cancer (AJCC) and the International Union Against Cancer (UICC) definitions and method of sizing.

Quality of Randomized Controlled Trials Reporting in the Treatment of Sarcomas

PURPOSE Randomized controlled trials (RCTs) represent the best evidence in oncology practice. The aim of this study was to assess the reporting quality of sarcoma RCTs and to identify significant predictors of quality. PATIENTS AND METHODS Two investigators searched MEDLINE for pediatric and adult bone and soft tissue sarcoma RCTs published between January 1988 and December 2008. The quality of each report was assessed by using a 15-point overall reporting quality score based on 15 items from the revised Consolidated Standards of Reporting Trials (CONSORT) statement (overall quality score [OQS] range, 0 to 15 points). Concealment of allocation, appropriate blinding, and analysis according to intention-to-treat principle were assessed separately because of their crucial methodologic importance by using a 3-point key methodologic index score (MIS; range, 0 to 3). RESULTS We retrieved 72 relevant RCTs that included 16,029 patients. The median OQS was 9.5. Allocation concealment, blinding, and analysis by intent to treat were reported only in 21 (29%), nine (12.5%), and 23 (32%) of the 72 RCTs, respectively. The median MIS was 1 with a minimum of 0 and a maximum of 2. On multivariate analysis, publication after 1996 and high impact factor remained independent and significant predictors of improved OQS. The sole variable associated with improved MIS was the publication of chemotherapy-only trials. CONCLUSION Although the overall quality of sarcoma RCTs reporting has improved over time, reporting of key methodologic issues remains poor. This may lead to biased interpretation of sarcoma trial results.

Benefit of adjuvant trastuzumab-based chemotherapy in T1ab node-negative HER2-overexpressing breast carcinomas: a multicenter retrospective series

BACKGROUND Randomized clinical trials showed the benefit of adjuvant trastuzumab-based chemotherapy (ATBC) for node-positive and/or >1 cm HER2+ breast carcinomas. No efficacy data have been published on ATBC in large series of pT1abN0 HER2+ tumors. PATIENTS AND METHODS This retrospective study evaluated 276 cases of pT1abN0 HER2+ breast tumors in eight French cancer centers. Factors associated with prognosis and ATBC prescription were analyzed. RESULTS A total of 129 cases (47%) were treated with ATBC (ATBC+), 19 with chemotherapy alone, 5 with trastuzumab alone, and 123 (45%) with neither trastuzumab nor chemotherapy (ATBC-). ATBC use was associated with the date of diagnosis (before or after June 2005) and with poor prognostic features. At a median follow-up of 44 months, there were 13 recurrences in the ATBC- group and 2 in the ATBC+ group. ATBC was associated with a significant survival benefit (99% 40-month disease-free survival for ATBC+ versus 93% for ATBC- cases; P = 0.018). Lack of hormone receptors (HRs) and the presence of lymphovascular invasion (LVI) were significantly associated with a poor prognosis and a greater benefit of ATBC. CONCLUSIONS ATBC was associated with a significantly reduced risk of recurrence in pT1abN0 HER2+ tumors, and was more beneficial in HR- and/or LVI+ tumors.