Cardiac safety of dual anti-HER2 blockade with pertuzumab plus trastuzumab in early HER2-positive breast cancer in the APHINITY trial

BACKGROUND

Trastuzumab increases the incidence of cardiac events (CEs) in patients with breast cancer (BC). Dual blockade with pertuzumab (P) and trastuzumab (T) improves BC outcomes and is the standard of care for high-risk human epidermal growth factor receptor 2 (HER2)-positive early BC patients. We analyzed the cardiac safety of P and T in the phase III APHINITY trial.

PATIENTS AND METHODS

Left ventricular ejection fraction (LVEF) ≥ 55% was required at study entry. LVEF assessment was carried out every 3 months during treatment, every 6 months up to month 36, and yearly up to 10 years. Primary CE was defined as heart failure class III/IV and a significant decrease in LVEF (defined as ≥10% from baseline and to <50%), or cardiac death. Secondary CE was defined as a confirmed significant decrease in LVEF, or CEs confirmed by the cardiac advisory board.

RESULTS

The safety analysis population consisted of 4769 patients. With 74 months of median follow-up, CEs were observed in 159 patients (3.3%): 83 (3.5%) in P + T and 76 (3.2%) in T arms, respectively. Most CEs occurred during anti-HER2 therapy (123; 77.4%) and were asymptomatic or mildly symptomatic decreases in LVEF (133; 83.6%). There were two cardiac deaths in each arm (0.1%). Cardiac risk factors indicated were age > 65 years, body mass index ≥ 25 kg/m², baseline LVEF between 55% and <60%, and use of an anthracycline-containing chemotherapy regimen. Acute recovery from a CE based on subsequent LVEF values was observed in 127/155 patients (81.9%).

CONCLUSIONS

Dual blockade with P + T does not increase the risk of CEs compared with T alone. The use of anthracycline-based chemotherapy increases the risk of a CE; hence, non-anthracycline chemotherapy may be considered, particularly in patients with cardiovascular risk factors.

Clinical significance of CD73 in triple-negative breast cancer: multiplex analysis of a phase III clinical trial

Background

CD73 is an ecto-enzyme that promotes tumor immune escape through the production of immunosuppressive extracellular adenosine in the tumor microenvironment. Several CD73 inhibitors and adenosine receptor antagonists are being evaluated in phase I clinical trials.

Patients and methods

Full-face sections from formalin-fixed paraffin-embedded primary breast tumors from 122 samples of triple-negative breast cancer (TNBC) from the BIG 02-98 adjuvant phase III clinical trial were included in our analysis. Using multiplex immunofluorescence and image analysis, we assessed CD73 protein expression on tumor cells, tumor-infiltrating leukocytes and stromal cells. We investigated the associations between CD73 protein expression with disease-free survival (DFS), overall survival (OS) and the extent of tumor immune infiltration.

Results

Our results demonstrated that high levels of CD73 expression on epithelial tumor cells were significantly associated with reduced DFS, OS and negatively correlated with tumor immune infiltration (Spearman's R= -0.50, P < 0.0001). Patients with high levels of CD73 and low levels of tumor-infiltrating leukocytes had the worse clinical outcome.

Conclusions

Taken together, our study provides further support that CD73 expression is associated with a poor prognosis and reduced anti-tumor immunity in human TNBC and that targeting CD73 could be a promising strategy to reprogram the tumor microenvironment in this BC subtype.

Estimating the benefits of therapy for early-stage breast cancer: the St. Gallen International Consensus Guidelines for the primary therapy of early breast cancer 2019

BACKGROUND

The 16th St. Gallen International Breast Cancer Conference 2019 in Vienna, Austria reviewed substantial new evidence on loco-regional and systemic therapies for early breast cancer.

DESIGN

Treatments were assessed in light of their intensity, duration and side-effects, estimating the magnitude of clinical benefit according to stage and biology of the disease. The Panel acknowledged that for many patients, the impact of adjuvant therapy or the adherence to specific guidelines may have modest impact on the risk of breast cancer recurrence or overall survival. For that reason, the Panel explicitly encouraged clinicians and patients to routinely discuss the magnitude of benefit for interventions as part of the development of the treatment plan.

RESULTS

The guidelines focus on common ductal and lobular breast cancer histologies arising in generally healthy women. Special breast cancer histologies may need different considerations, as do individual patients with other substantial health considerations. The panelists' opinions reflect different interpretation of available data and expert opinion where is lack of evidence and sociocultural factors in their environment such as availability of and access to medical service, economic resources and reimbursement issues. Panelists encourage patient participation in well-designed clinical studies whenever available.

CONCLUSIONS

With these caveats in mind, the St. Gallen Consensus Conference seeks to provide guidance to clinicians on appropriate treatments for early-stage breast cancer and guidance for weighing the realistic tradeoffs between treatment and toxicity so that patients and clinical teams can make well-informed decisions on the basis of an honest reckoning of the magnitude of clinical benefit.

Are we assuming too much with our statistical assumptions? Lessons learned from the ALTTO trial

BACKGROUND

Design, conduct, and analysis of randomized clinical trials (RCTs) with time to event end points rely on a variety of assumptions regarding event rates (hazard rates), proportionality of treatment effects (proportional hazards), and differences in intensity and type of events over time and between subgroups.

DESIGN AND METHODS

In this article, we use the experience of the recently reported Adjuvant Lapatinib and/or Trastuzumab Treatment Optimization (ALTTO) RCT, which enrolled 8381 patients with human epidermal growth factor 2-positive early breast cancer between June 2007 and July 2011, to highlight how routinely applied statistical assumptions can impact RCT result reporting.

RESULTS AND CONCLUSIONS

We conclude that (i) futility stopping rules are important to protect patient safety, but stopping early for efficacy can be misleading as short-term results may not imply long-term efficacy, (ii) biologically important differences between subgroups may drive clinically different treatment effects and should be taken into account, e.g. by pre-specifying primary subgroup analyses and restricting end points to events which are known to be affected by the targeted therapies, (iii) the usual focus on the Cox model may be misleading if we do not carefully consider non-proportionality of the hazards. The results of the accelerated failure time model illustrate that giving more weight to later events (as in the log rank test) can affect conclusions, (iv) the assumption that accruing additional events will always ensure gain in power needs to be challenged. Changes in hazard rates and hazard ratios over time should be considered, and (v) required family-wise control of type 1 error ≤ 5% in clinical trials with multiple experimental arms discourages investigations designed to answer more than one question.

TRIAL REGISTRATION

clinicaltrials.gov Identifier NCT00490139.

Abstract PD5-09: Immune parameters associated with survival in triple negative and HER2-positive breast cancer patients with 10 years of follow-up

The clinical utility of tumor-infiltrating lymphocytes (TIL) is actively being investigated in breast cancer (BC). It is unclear whether TIL spatial location and organization in tertiary lymphoid structures (TLS) have an impact on prognosis. Additionally, the significance of PD-1 and PD-L1 expression is being debated due to conflicting data from several studies. We hypothesize that the presence, extent and spatial location of multiple immune biomarkers, reflecting ongoing immune responses, will be consistently associated with a good prognosis in highly infiltrated BC [triple-negative (TNBC) and HER2+].

The relationship between these immune biomarkers and clinical outcome was examined in the TNBC and HER2+ cohorts of node-positive BC patients enrolled in the BIG 02-98 adjuvant phase III trial with available material for immunohistochemical (IHC) labeling (N=113 and N=136, respectively). HER2+ patients did not receive trastuzumab. Dual IHC staining was performed on full-face consecutive tissue sections. Scoring was independently performed by two pathologists, blinded to the clinical data, and included: global, intratumoral and stromal TIL and TLS, assessed on CD3/CD20 slides; the percentage and location of PD-1 and PD-L1 expression, assessed on PD-1/PD-L1 slides. TIL were considered as a categorical variable with different cut-offs used for each parameter and for each cohort (TNBC and HER2+). Invasive disease-free survival (I-DFS) and overall survival (OS) were analyzed (median follow-up: 10 years). Cox proportional hazard models were used for survival analyses.

The TNBC cohort revealed an association between global TIL and outcome [adjusted hazard ratio (HR) for I-DFS: 0.27 (0.15-0.51); OS: 0.26 (0.13-0.53)]. Similar results were observed for stromal and intratumoral TIL. PD-L1 expression within TLS was an independent predictor of OS, after adjustment for tumor size and age [HR: 0.30 (0.09-0.99)]. Multivariate analysis reveals this effect was principally driven by high stromal TIL (&gt;17.5% based on CD3/CD20 assessment) (χ2 OS: p=0.009). In contrast, no significant prognostic associations were found in the overall HER2+ cohort. However high T cell TIL were associated with improved I-DFS and OS in the ER-/HER2+ group [I-DFS: 0.34 (0.14-0.80); OS: 0.32 (0.12-0.86)] and stromal TIL were associated with improved I-DFS in the ER+/HER2+ group [HR: 0.29 (0.09-0.94)] (univariate analyses). No significant associations between the number of TLS nor the expression of PD-1 with outcomes were observed in either cohorts.

The presence of PD-L1+ TLS, driven by high baseline TIL, was associated with an excellent prognosis in node-positive TNBC. This observation might reflect specific immune activities taking place in these mini lymph node-like structures adjacent to the tumor bed where specific antitumor memory immune responses could be generated. No different prognostic impact was observed when analyzing TIL spatial location. Although the statistical power of the study might be limited, in line with previous findings our data reveal that, among the immune parameters evaluated, TIL are the strongest predictor of outcome in TNBC, while PD-L1+ TLS could be a new and important parameter that requires further investigation.

Citation Format: Solinas C, de Wind A, Van den Eynden G, Ameye L, Garaud S, De Silva P, Boisson A, Noel G, Langouo Fontsa M, Buisseret L, de Azambuja E, Francis PA, Di Leo A, Crown JP, Sotiriou C, Larsimont D, Paesmans M, Piccart-Gebhart M, Willard-Gallo K. Immune parameters associated with survival in triple negative and HER2-positive breast cancer patients with 10 years of follow-up [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD5-09.

Pathway level alterations rather than mutations in single genes predict response to HER2-targeted therapies in the neo-ALTTO trial

Background

We performed whole-exome sequencing of pretreatment biopsies and examined whether genome-wide metrics of overall mutational load, clonal heterogeneity or alterations at variant, gene, and pathway levels are associated with treatment response and survival.

Patients and Methods

Two hundred and three biopsies from the NeoALTTO trial were analyzed. Mutations were called with MuTect, and Strelka, using pooled normal DNA. Associations between DNA alterations and outcome were evaluated by logistic and Cox-proportional hazards regression.

Results

There were no recurrent single gene mutations significantly associated with pathologic complete response (pCR), except PIK3CA [odds ratio (OR) = 0.42, P = 0.0185]. Mutations in 33 of 714 pathways were significantly associated with response, but different genes were affected in different individuals. PIK3CA was present in 23 of these pathways defining a ‘trastuzumab resistance-network’ of 459 genes. Cases with mutations in this network had low pCR rates to trastuzumab (2/50, 4%) compared with cases with no mutations (9/16, 56%), OR = 0.035; P < 0.001. Mutations in the ‘Regulation of RhoA activity’ pathway were associated with higher pCR rate to lapatinib (OR = 14.8, adjusted P = 0.001), lapatinib + trastuzumab (OR = 3.0, adjusted P = 0.09), and all arms combined (OR = 3.77, adjusted P = 0.02). Patients (n = 124) with mutations in the trastuzumab resistance network but intact RhoA pathway had 2% (1/41) pCR rate with trastuzumab alone (OR = 0.026, P = 0.001) but adding lapatinib increased pCR rate to 45% (17/38, OR = 1.68, P = 0.3). Patients (n = 46) who had no mutations in either gene set had 6% pCR rate (1/15) with lapatinib, but had the highest pCR rate, 52% (8/15) with trastuzumab alone.

Conclusions

Mutations in the RhoA pathway are associated with pCR to lapatinib and mutations in a PIK3CA-related network are associated with resistance to trastuzumab. The combined mutation status of these two pathways could define patients with very low response rate to trastuzumab alone that can be augmented by adding lapatinib or substituting trastuzumab with lapatinib.

Abstract PD6-07: Clinical significance of CD73 expression in triple-negative breast cancer from the BIG 02-98 adjuvant phase III clinical trial

Background: CD73 is an ecto-enzyme that promotes tumor immune escape through the production of immunosuppressive extracellular adenosine in the tumor microenvironment. Several CD73 inhibitors and adenosine receptor antagonists are being evaluated in phase I clinical trials.

Objective: To investigate the prognosis significance of CD73 in human triple-negative breast cancer.

Design and setting: This is a prospective-retrospective biomarker analysis. Using multiplex immunofluorescence and image analysis, we assessed CD73 protein expression on tumor cells, tumor-infiltrating leukocytes and stromal cells on full-face sections from formalin-fixed paraffin-embedded primary breast tumors.

Participants: 122 samples of triple-negative breast cancer from the BIG 02-98 adjuvant phase III clinical trial were included in our analysis. This trial compared the addition of taxanes to anthracyclines-based chemotherapy in node-positive breast cancer.

Results: Our results demonstrated that high levels of CD73 expression on epithelial tumor cells were significantly associated with reduced disease-free survival (DFS) and overall survival (OS) in patients with triple-negative breast cancer. Using the median as a threshold between low and high levels of CD73 on epithelial cells, hazard ratios (HR) adjusted for grade, number of positive lymph nodes and tumor size, were of 2.21 (95% confidence interval (CI): 1.15-4.25); p=0.02 for DFS and of 2.47 (95%CI: 1.21-5.07); p=0.01 for OS. CD73 expression negatively correlated with tumor immune infiltration (Spearman's R= -0.50, p&lt;0.0001). Patients with high levels of CD73 and low levels of tumor-infiltrating leukocytes had the worse clinical outcome (HR: 4.24 (1.90-9.45), p&lt;0.001 for DFS, HR: 3.91 (1.65-9.31), p=0.002 for OS) compared to patients with low CD73 and high tumor-immune infiltration. Flow cytometric analysis of tumor-infiltrating leukocytes revealed a high frequency of CD73-expressing B cells and higher CD73 expression on tumor-infiltrating myeloid cells and natural killer cells compared to peripheral blood.

Conclusion and relevance: Taken together, our study provides further support that CD73 expression is associated with a poor prognosis and reduced anti-tumor immunity in human triple-negative breast cancer and that targeting CD73 could be a promising strategy to reprogram the tumor microenvironment in this breast cancer subtype.

Citation Format: Buisseret L, Pommey S, Allard B, Garaud S, Bergeron MA, Cousineau I, Ameye L, Paesmans M, Crown JPA, Di Leo A, Piccart-Gebhart M, Willard-Gallo K, Sotiriou C, Stagg J. Clinical significance of CD73 expression in triple-negative breast cancer from the BIG 02-98 adjuvant phase III clinical trial [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr PD6-07.

Abstract P2-09-01: T-cell receptor beta chain variable region (TRBV) expression patterns predict response to combined trastuzumab/lapatinib treatment in the NeoALTTO/BIG-1-06 trial

Background: Dual anti-HER2 blockade resulted in increased pathologic complete response rate (pCR) in the 3 arm NeoALTTO trial. High immune gene expression and the absence of PIK3CA pathway mutations are predictive of pCR in all treatment arms but no markers were identified that could predict which patients require dual HER2 targeted therapy. The goal of this analysis was to examine if TRBV expression could add to the predictive function of previously identified immune markers.

Patients and Methods: We analyzed RNA and Whole Exome sequencing data from 245 cancers (54% of all patients) included in the trial. The TRBV reference sequences were obtained from the International ImMunoGeneTics information system. Reads were aligned using a custom BLAST mapping pipeline and normalized by the total number of aligned reads in each sample. We calculated 3 T cell receptor metrics for each tumor including (i) total TRBV chain expression level, (ii) Shannon entropy of the normalized unique TRBV-expression frequencies which reflect TCR diversity and (iii) we also used non-negative matrix factorization (NMF) to define TRBV co-expression metagenes (TRBVMG). We evaluated correlation between these metrics and immune and proliferation gene expression signatures and genomic features of the cancer including clonal heterogeneity and mutation load. We assessed association between TRBV and pCR using multivariate logistic regression.

Results: 65 distinct TRBV variants showed heterogeneous expression levels across cancers with strong co-expression patterns. Total TRBV expression correlated strongly with immune metagene expression (Spearman's ρ=0.93, P&lt;0.001), but entropy had a weaker, inverse correlation with immune metagene expression (Spearman's ρ=-0.40, P&lt;0.001). Associations between TRBV metrics and mutation load and clonal heterogeneity were weak. pCR correlated with higher total TRBV expression (Spearman's ρ=0.17, P&lt;0.05). Correlation between entropy and pCR was non-significant (odds ratio (OR) for regressing entropy with pCR was &lt;1). NMF identified 4 distinct TRBVMGs that showed substantial expression variation within immune cell rich cancers. ER-status, proliferation and immune-gene expression adjusted logistic regression analysis including a treatment-arm interaction term revealed that TRBVMG-2, characterized by high expression of TRBV4.3, TRBV6.3 and TRBV7.2 variants, was associated with higher pCR rate in patients treated with trastuzumab plus lapatinib (Interaction OR=3.23 adjusted P=0.03). In immune-rich cancers, TRBVMG-2 expression above the median was associated with higher pCR rate in the dual HER2 targeted treatment arm compared to the other arms (68% vs 21%, Fisher exact test P&lt;0.001). Patients with immune cell rich cancers but TRBVMG-2 expression below the median had similar pCR rates in all arms (42% monotherapy vs. 28% dual therapy, P=0.46).

Conclusions: TRBV expression pattern can provide predictive information beyond known immune gene expression signatures. High expression of TRBV4.3, TRBV6.3 and TRBV7.2 variants is associated with higher pCR rate with dual HER2 targeted and paclitaxel neoadjuvant therapy.

Citation Format: Powles R, Redmond D, Sotiriou C, Loi S, Fumagalli D, Nuciforo P, Harbeck N, de Azambuja E, Sarp S, Di Cosimo S, Huober J, Baselga J, Piccart-Gebhart M, Elemento O, Hatzis C, Pusztai L. T-cell receptor beta chain variable region (TRBV) expression patterns predict response to combined trastuzumab/lapatinib treatment in the NeoALTTO/BIG-1-06 trial [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-09-01.

De-escalating and escalating treatments for early-stage breast cancer: the St. Gallen International Expert Consensus Conference on the Primary Therapy of Early Breast Cancer 2017

The 15th St. Gallen International Breast Cancer Conference 2017 in Vienna, Austria reviewed substantial new evidence on loco-regional and systemic therapies for early breast cancer. Treatments were assessed in light of their intensity, duration and side-effects, seeking where appropriate to escalate or de-escalate therapies based on likely benefits as predicted by tumor stage and tumor biology. The Panel favored several interventions that may reduce surgical morbidity, including acceptance of 2 mm margins for DCIS, the resection of residual cancer (but not baseline extent of cancer) in women undergoing neoadjuvant therapy, acceptance of sentinel node biopsy following neoadjuvant treatment of many patients, and the preference for neoadjuvant therapy in HER2 positive and triple-negative, stage II and III breast cancer. The Panel favored escalating radiation therapy with regional nodal irradiation in high-risk patients, while encouraging omission of boost in low-risk patients. The Panel endorsed gene expression signatures that permit avoidance of chemotherapy in many patients with ER positive breast cancer. For women with higher risk tumors, the Panel escalated recommendations for adjuvant endocrine treatment to include ovarian suppression in premenopausal women, and extended therapy for postmenopausal women. However, low-risk patients can avoid these treatments. Finally, the Panel recommended bisphosphonate use in postmenopausal women to prevent breast cancer recurrence. The Panel recognized that recommendations are not intended for all patients, but rather to address the clinical needs of the majority of common presentations. Individualization of adjuvant therapy means adjusting to the tumor characteristics, patient comorbidities and preferences, and managing constraints of treatment cost and access that may affect care in both the developed and developing world.

Abstract P2-09-05: 12 years' median follow up (MFU) of BIG 1-98: Adjuvant letrozole, tamoxifen and their sequence for postmenopausal women with endocrine responsive early breast cancer

Background

The Breast International Group (BIG) 1-98 study is a randomized, phase 3, double-blind trial that compared five yrs of adjuvant treatment with letrozole, tamoxifen, or their sequence in postmenopausal women with hormone-receptor–positive early breast cancer. The study is conducted by the International Breast Cancer Study Group (IBCSG) on behalf of BIG. 8010 patients (pts) were enrolled between March 1998 and May 2003, and first results demonstrating a significant DFS benefit favoring letrozole compared with tamoxifen were reported in 2005 at 25.8 months' MFU. Subsequent updates showed continuing DFS benefit and updated results published in 2011 at 8.1 yrs' MFU showed OS benefit. Industry-sponsorship of the original BIG 1-98 ended in 2010; IBCSG launched an observational, non-interventional long-term follow-up study (BIG 1-98 LTFU) to collect survival, disease status and adverse events for an additional 5 yrs. We report results from BIG 1-98 LTFU at 12 yrs' MFU.

Methods

The original trial includes the 8010 patients enrolled. The potential BIG 1-98 LTFU cohort consisted of 148 academic medical centers with a maximum of 6843 pts who were alive and continuing follow-up when the original study ended. Response bias was addressed using weighting class adjustments estimated using multivariable logistic regression. Unadjusted incidence rates are reported here per 1000 pt-yrs with 95% Poisson confidence intervals. An updated abstract will include adjusted incidence rates, as well as estimates of OS and DFS based on a weighted Kaplan-Meier approach. The database will close in July 2016.

Results

As of May 2016, 81 centers participated in the BIG 1-98 LTFU study, contributing data from approximately 3900 pts (57%) and extending MFU to 12 yrs. Compared with the potential cohort of 6843 pts, the ~3900 in the LTFU analytic cohort were more likely to be under age 65 yrs at enrollment, have node-positive disease, and have tumors that were &lt; 2 cm, PgR positive (≥1%), and with no evidence of peritumoral vascular invasion. Extended adjuvant endocrine therapy for primary BC was continued in 2% of pts. Unadjusted incidence estimates of myocardial infarction increased during LTFU, while incidence of thromboembolic events and osteoporosis decreased (Table). Variations in incidence rates were noted depending on recording mechanism (e.g. registry, clinic visit, telephone, information from family).

 Unadjusted Incidence Rate/1000 pt-yrs (95% CI)Adverse EventDuring original studyDuring LTFUMyocardial Infarction1.7 (1.4-2.0)3.5 (2.7-4.5)Thromboembolic event6.0 (5.4-6.6)2.5 (1.8-3.3)Osteoporosis23.6 (22.5-24.9)18.2 (16.3-20.3)Bone fractures17.2 (16.2-18.3)15.0 (13.2-16.9)

Overall 1845 deaths were reported; the unadjusted incidence of death was lower in the original study compared with during LTFU (21.9 vs. 26.6/1000 pt-yrs); incidence remained relatively stable for pts assigned to tamoxifen (24.9 vs. 25.2/1000 pt-yrs), and increased for pts assigned to letrozole (22.0 vs. 27.1/1000 pt-yrs).

Conclusions

The BIG 1-98 LTFU study has been successfully conducted. The additional data from the BIG 1-98 LTFU study provides important long-term clinical information about OS, DFS and adverse events.

Citation Format: Thürlimann B, Giobbie-Hurder A, Colleoni M, Jensen M-B, Ejlertsen B, de Azambuja E, Neven P, Láng I, Gladieff L, Bonnefoi H, Harvey VJ, Spazzapan S, Tondini C, Price K, Piccart-Gebhart M, Regan MM, Gelber RD, Coates AS, Goldhirsch A. 12 years' median follow up (MFU) of BIG 1-98: Adjuvant letrozole, tamoxifen and their sequence for postmenopausal women with endocrine responsive early breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-09-05.

Abstract S5-01: Whole exome sequencing of pre-treatment biopsies from the neoALTTO trial to identify DNA aberrations associated with response to HER2-targeted therapies

Background: We examined if alterations in nucleic acid variants, genes, pathways, and overall mutational load and clonal entropy are associated with pathologic complete response (pCR) and survival after neoadjuvant anti-HER2 therapies in the NeoALTTO trial.

Methods: Whole exome sequencing was performed of 203 baseline biopsies with outcome information. The mean nucleotide coverage was 150x with &gt;90% of target bases showing &gt; 30x coverage in &gt; 99% of samples. Somatic mutations were called by MuTect and indels by Strelka, using pooled reference normal DNA. Significantly mutated genes (FDR&lt;10%) were identified by MutSigCV. Mutations in 714 canonical biological pathways were assessed and mutational load and genome clonal entropy (MATH) were calculated. Association with pCR and survival were evaluated by logistic regression adjusted for ER status and Cox-proportional hazards regression.

Results: Only 12 genes had mutation rates significantly above background and among these only PI3KCA was associated with lower pCR rate (OR=0.42, p=0.019). Genes with somatic mutations in more than 10 patients were also assessed, but none were associated with pCR or survival. Clonal entropy or adjusted mutation load also did not correlate with response. Mutations in 33 pathways showed significant association with response in the entire cohort. In the trastuzumab arm, 23 of the 33 pathways showed an association with response but none was independent of PIK3CA mutation. We constructed "PIK3CA-gene network" that included all unique genes (n=439) from theese 23 pathways. Of the 66 patients in the trastuzumab arm, 50 carried at least one mutation in one of the 439 genes and among these only 2 achieved pCR (4%) compared to 9 of 16 pCR (56%) among the wild type (OR=0.035; p &lt; 0.001). The same genes/mutations had little impact on pCR in the lapatinib arm (pCR 20%). In the lapatinib arm, mutations in 3 pathways conferred higher probability of pCR. The "Regulation of RhoA activity" pathway, had the most significant association with pCR in the entire cohort (OR=3.77, p=0.0009) and in the lapatininb (pCR 67% vs 17%, OR=14.8, p=0.008) and lapatinib + trastuzumab (OR=3.0, p=0.06) arms, but not in the trastuzumab arm (OR=1.4, p=0.7). Event free and overall survival were also significantly higher in patients who had mutations in this pathway. Twenty seven of the 48 genes in this pathway had mutations affecting 33 patients but different genes were affected in different individuals.

Conclusions: There are no high frequency recurrent single mutations associated with response to HER2-targeted therapies, other than PIK3CA. We identified several biological pathways, including RhoA activity, and a network of PIK3CA associated genes that are significantly associated with response when affected by mutations, however, different genes are mutated in different individuals.

Citation Format: Pusztai L, Shi W, Jiang T, Nuciforo P, Holmes E, Harbeck N, Sotiriou C, Rimm D, Hatzis C, de la Peña L, Armour A, Piccart-Gebhart M, Baselga J. Whole exome sequencing of pre-treatment biopsies from the neoALTTO trial to identify DNA aberrations associated with response to HER2-targeted therapies. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr S5-01.

Tailoring therapies--improving the management of early breast cancer: St Gallen International Expert Consensus on the Primary Therapy of Early Breast Cancer 2015

The 14th St Gallen International Breast Cancer Conference (2015) reviewed substantial new evidence on locoregional and systemic therapies for early breast cancer. Further experience has supported the adequacy of tumor margins defined as 'no ink on invasive tumor or DCIS' and the safety of omitting axillary dissection in specific cohorts. Radiotherapy trials support irradiation of regional nodes in node-positive disease. Considering subdivisions within luminal disease, the Panel was more concerned with indications for the use of specific therapies, rather than surrogate identification of intrinsic subtypes as measured by multiparameter molecular tests. For the treatment of HER2-positive disease in patients with node-negative cancers up to 1 cm, the Panel endorsed a simplified regimen comprising paclitaxel and trastuzumab without anthracycline as adjuvant therapy. For premenopausal patients with endocrine responsive disease, the Panel endorsed the role of ovarian function suppression with either tamoxifen or exemestane for patients at higher risk. The Panel noted the value of an LHRH agonist given during chemotherapy for premenopausal women with ER-negative disease in protecting against premature ovarian failure and preserving fertility. The Panel noted increasing evidence for the prognostic value of commonly used multiparameter molecular markers, some of which also carried prognostic information for late relapse. The Panel noted that the results of such tests, where available, were frequently used to assist decisions about the inclusion of cytotoxic chemotherapy in the treatment of patients with luminal disease, but noted that threshold values had not been established for this purpose for any of these tests. Multiparameter molecular assays are expensive and therefore unavailable in much of the world. The majority of new breast cancer cases and breast cancer deaths now occur in less developed regions of the world. In these areas, less expensive pathology tests may provide valuable information. The Panel recommendations on treatment are not intended to apply to all patients, but rather to establish norms appropriate for the majority. Again, economic considerations may require that less expensive and only marginally less effective therapies may be necessary in less resourced areas. Panel recommendations do not imply unanimous agreement among Panel members. Indeed, very few of the 200 questions received 100% agreement from the Panel. In the text below, wording is intended to convey the strength of Panel support for each recommendation, while details of Panel voting on each question are available in supplementary Appendix S2, available at Annals of Oncology online.

The landscape of medical oncology in Europe by 2020

BACKGROUND

In the United States, there will be a shortage of medical oncologists (MO) by 2020. However, this information is not available for Europe. The aim of this study was to assess the current number of MO in the 27 European Union (27-EU) countries and to predict their availability by 2020.

MATERIAL AND METHODS

Between June 2012 and January 2013, a survey was submitted to health authorities, medical oncology societies, and personal contacts in all 27-EU countries in order to gather annual data on the number of practicing MO. Data were collected by e-mail, telephone contact, or through research on official websites. Data regarding cancer incidence in 2008 and projections for 2015 and 2020 were obtained through Globocan. The mean annual increase in the number of MO was calculated for each country. The total number of MO by 2015 and 2020 was estimated, and the ratio of new cancer cases versus number of MO was calculated for 2008, 2015, and 2020.

RESULTS

Twelve countries provided sufficient data. The average mean annual increase in the total number of MO was 5.3% (range 1.8%-8.7%), with Belgium being the lowest and UK the highest. The 2008 ratio of cancer cases versus MO was lowest in Hungary (113) and highest in UK (1067). A favorable decrease in this ratio was estimated in most countries.

CONCLUSION

Our estimates, based on incidence and not on prevalence, indicate that MO availability will probably meet the projected need in most of the 12 countries analyzed, provided that: (i) these countries maintain their rate of annual increase in MO; and (ii) no unforeseen changes occur in cancer incidence. Unfortunately, minimal information is available for Eastern Europe. Our data call for the prospective surveillance of the cancer burden and MO availability to ensure adequate and equal care for cancer patients throughout Europe.

Genome-wide gene expression profiling to predict resistance to anthracyclines in breast cancer patients

Validated biomarkers predictive of response/resistance to anthracyclines in breast cancer are currently lacking. The neoadjuvant Trial of Principle (TOP) study, in which patients with estrogen receptor (ER)–negative tumors were treated with anthracycline (epirubicin) monotherapy, was specifically designed to evaluate the predictive value of topoisomerase II-alpha (TOP2A) and develop a gene expression signature to identify those patients who do not benefit from anthracyclines. Here we describe in details the contents and quality controls for the gene expression and clinical data associated with the study published by Desmedt and colleagues in the Journal of Clinical Oncology in 2011 (Desmedt et al., 2011). We also provide R code to easily access the data and perform the quality controls and basic analyses relevant to this dataset.

Phase I trial combining temozolomide plus lapatinib for the treatment of brain metastases in patients with HER2-positive metastatic breast cancer: the LAPTEM trial

BACKGROUND

Brain metastases (BMs) pose a clinical challenge in breast cancer (BC). Lapatinib or temozolomide showed activity in BM. Our study assessed the combination of both drugs as treatment for patients with HER2-positive BC and BM.

METHODS

Eighteen patients were enrolled, with sixteen of them having recurrent or progressive BM. Any type of previous therapy was allowed, and disease was assessed by gadolinium (Gd)-enhanced magnetic resonance imaging (MRI). The primary end points were the evaluation of the dose-limiting toxicities (DLTs) and the determination of the maximum-tolerated dose (MTD). The secondary end points included objective response rate, clinical benefit and duration of response.

RESULTS

The lapatinib-temozolomide regimen showed a favorable toxicity profile because the MTD could not be reached. The most common adverse events (AEs) were fatigue, diarrhea and constipation. Disease stabilization was achieved in 10 out of 15 assessable patients. The estimated median survival time for the 16 patients with BM reached 10.94 months (95% CI: 1.09-20.79), whereas the median progression-free survival time was 2.60 months [95% confidence interval (CI): 1.82-3.37].

CONCLUSIONS

The lapatinib-temozolomide combination is well tolerated. Preliminary evidence of clinical activity was observed in a heavily pretreated population, as indicated by the volumetric reductions occurring in brain lesions.

Personalizing the treatment of women with early breast cancer: highlights of the St Gallen International Expert Consensus on the Primary Therapy of Early Breast Cancer 2013

The 13th St Gallen International Breast Cancer Conference (2013) Expert Panel reviewed and endorsed substantial new evidence on aspects of the local and regional therapies for early breast cancer, supporting less extensive surgery to the axilla and shorter durations of radiation therapy. It refined its earlier approach to the classification and management of luminal disease in the absence of amplification or overexpression of the Human Epidermal growth factor Receptor 2 (HER2) oncogene, while retaining essentially unchanged recommendations for the systemic adjuvant therapy of HER2-positive and 'triple-negative' disease. The Panel again accepted that conventional clinico-pathological factors provided a surrogate subtype classification, while noting that in those areas of the world where multi-gene molecular assays are readily available many clinicians prefer to base chemotherapy decisions for patients with luminal disease on these genomic results rather than the surrogate subtype definitions. Several multi-gene molecular assays were recognized as providing accurate and reproducible prognostic information, and in some cases prediction of response to chemotherapy. Cost and availability preclude their application in many environments at the present time. Broad treatment recommendations are presented. Such recommendations do not imply that each Panel member agrees: indeed, among more than 100 questions, only one (trastuzumab duration) commanded 100% agreement. The various recommendations in fact carried differing degrees of support, as reflected in the nuanced wording of the text below and in the votes recorded in supplementary Appendix S1, available at Annals of Oncology online. Detailed decisions on treatment will as always involve clinical consideration of disease extent, host factors, patient preferences and social and economic constraints.

HER2 staining intensity in HER2-positive disease: relationship with FISH amplification and clinical outcome in the HERA trial of adjuvant trastuzumab

BACKGROUND

Trastuzumab treatment improves survival of HER2-positive primary breast cancer. HER2 staining intensity varies widely in HER2-positive tumours.

PATIENTS AND METHODS

We investigated whether differences in immunohistochemical (IHC) staining intensity for HER2 in HER2-positive tumors (IHC 3+ or FISH ratio ≥2.0) was associated with prognosis or benefit from trastuzumab treatment in patients randomized to 1 year or no trastuzumab in the HERceptin Adjuvant (HERA) trial. Median follow-up was 2 years. The nested case-control analysis, included 425 patients (cases) with a disease-free survival (DFS) event and two matched controls (no DFS event) per case. Tissue sections stained for HER2 were assessed for HER2 staining intensity by image analysis.

RESULTS

HER2 staining intensity varied widely and correlated with HER2 gene copy number (Spearman, r = 0.498, P < 0.001) or less closely with HER2/CEP17 FISH ratio (r = 0.396, P < 0.001). We found no significant difference in DFS in the observation arm according to staining intensity (odds ratio [OR] change per 10 unit change in intensity: 1.015, 95% confidence interval [CI] 0.930-1.108) and no impact of staining intensity on benefit derived from 1-year trastuzumab (OR: 1.017, 95% CI 0.925-1.120).

CONCLUSIONS

Variability in HER2 staining in HER2-positive tumours has no role in clinical management with adjuvant trastuzumab.

HERA TRIAL NO

NCT00045032.

Overall survival benefit for sequential doxorubicin-docetaxel compared with concurrent doxorubicin and docetaxel in node-positive breast cancer--8-year results of the Breast International Group 02-98 phase III trial

Background In women with node-positive breast cancer, the Breast International Group (BIG) 02-98 tested the incorporation of docetaxel (Taxotere) into doxorubicin (Adriamycin)-based chemotherapy, and compared sequential and concurrent docetaxel. At 5 years, there was a trend for improved disease-free survival (DFS) with docetaxel. We present results at 8-year median follow-up and exploratory analyses within biologically defined subtypes. Methods Patients were randomly assigned to one of four treatments: (i) sequential control: doxorubicin (A) (75 mg/m(2)) × 4 →classical cyclophosphamide, methotrexate, 5-fluorouracil (CMF); (ii) concurrent control: doxorubicin, cyclophosphamide (AC)(60/600 mg/m(2)) × 4 →CMF; (iii) sequential docetaxel: A (75 mg/m(2)) × 3 → docetaxel (T) (100 mg/m(2)) × 3 → CMF and (iv) concurrent docetaxel: AT(50/75 mg/m(2)) × 4 →CMF. The primary comparison evaluated docetaxel efficacy regardless of the schedule. Exploratory analyses were undertaken within biologically defined subtypes. Results Two thousand eight hundred and eighty-seven patients were enrolled. After 93.4 months of median follow-up, there were 916 DFS events. For the primary comparison, there was no significant improvement in DFS from docetaxel [hazard ratio (HR) = 0.91, 95% confidence interval (CI) = 0.80-1.05, P = 0.187]. In secondary comparisons, sequential docetaxel significantly improved DFS compared with sequential control (HR = 0.81, 95% CI = 0.67-0.99, P = 0.036), and significantly improved DFS (HR = 0.84, 95% CI = 0.72-0.99, P = 0.035) and overall survival (OS) (HR = 0.79, 95% CI = 0.65-0.98, P = 0.028) compared with concurrent doxorubicin-docetaxel. Luminal-A disease had the best prognosis. HRs favored addition of sequential docetaxel in all subtypes, except luminal-A; but this observation was not statistically supported because of limited numbers. Conclusion With further follow-up, the sequential docetaxel schedule resulted in significantly better OS than concurrent doxorubicin-docetaxel, and continued to show better DFS than sequential doxorubicin-based control.

P4-17-01: Trastuzumab Does Not Increase the Incidence of Central Nervous System (CNS) Relapses in HER2−Positive Early Breast Cancer: The HERA Trial Experience

Background: Retrospective studies of HER2−positive metastatic breast cancer (BC) showed an incidence of CNS metastases of 21% to 34%. We investigated the incidence and clinical aspects of CNS relapse (CNS-R) in patients (pts) enrolled in the HERA trial, a prospectively randomized adjuvant trial in node + or high-risk node - HER2−positive early BC pts.

Methods: 3401 pts were randomized into the 1-year trastuzumab (1yT) or the observation (obs) arms of HERA (Piccart-Gebhart et al, 2005, Gianni et al, 2011). The cumulative incidences of first disease-free survival (DFS) events in the CNS vs other sites were estimated using competing risk analysis. The database of the main study had a clinical cut-off date of 9th June 2008. To obtain additional information regarding CNS-R (including occurrence of CNS-R after first DFS event), a specific CNS-directed questionnaire was sent to investigators of pts who were deceased as of July 2009. Information collected included the date of CNS-R, whether it was symptomatic, the type of CNS-R (brain metastases (BM) or meningeal carcinomatosis (MC)), methods of diagnosis, and treatments at the time of CNS-R. Results: 1yT significantly reduced the risk of other DFS events (p=0.000017, Gray's test), but not of CNS-R (p=0.55) as first event (see table). During the first year of follow up, CNS-R accounted for 15 (14.9%) of the 101 first DFS events in the 1yT arm and 15 (7.7%) of the 194 first DFS events in the obs arm. The analysis of baseline patient and tumor characteristics associated with CNS-R as first event confirmed known risk factors such as young age (&lt;35y), T3 tumor, ≥ 4 + LN, ER neg, and G3.

P3-05-01: Gene Profiling of Histopathologically Characterized Apocrine Breast Cancers

Background

Breast cancer is currently classified in 3 groups based on estrogen receptor alpha (ER) and human epidermal growth factor receptor 2 (HER2/ERBB2) gene expression: one basal-like (ER-ERBB2-), one HER2−enriched (ERBB2+) and one luminal (ER+). Yet, in transcriptome-based classifications, ER-ERBB2+ group partially overlaps with more recently defined ER-AR+ (androgen receptor positive) group. This type was named molecular apocrine, in reference to the histopathologically characterized apocrine carcinomas (H-Apo), in which a marked activation of AR signaling was demonstrated with a distinct proteomic signature. H-Apo tumors correspond to 1% of invasive breast carcinomas and are clearly morphological distinct from other AR+ tumors. However, no specific H-Apo transcriptome signature has been reported for this sub-group. In an effort to better characterize those tumors, we have performed a meta-analysis of genomic data, focusing on the ER- AR+ breast subset.

Samples and Methods: Chips were from Affymetrix array generations HG-U133. 258 profiles were unpublished and 1145 were from published or in press data. Gene expression was carried out after GC-RMA normalization. Unsupervised hierarchical clustering and other statistical analysis were performed with R software.

Results: 160 of the 1403 investigated tumors were ER-AR+. An unsupervised hierarchical clustering clearly identified a small subgroup of 14 closely tumors expressing high transcripts levels of PIP, HPGD, ACSM1, AR, SDR5A1, HS3DB1. This profile was very similar to the proteomic signature previously described for the H-Apo tumors. In addition, the pathology report, although available only for 4 of those14 tumors, described them as typical apocrine carcinomas. Taken together, these data suggested that this cluster was the H-Apo subgroup. Unexpectedly, when using the transcriptomic PAM50 classification, 13 were classified as Luminal and only 1 as HER2−enriched, although the 14 tumors were all ER-negative. CGH analysis with Agilent 244K chips was carried out with 25 ER- AR+ tumors, of which 5 were H-Apo carcinomas. Importantly, those 5 H-Apo tumors exhibited fewer DNA lesions than the other ER-AR+ apocrine tumors (17% copy number alterations in H-Apo group versus 41%, p=0.02). More CGH data are currently under investigations and will be discussed.

Discussion: The histopathologically characterized apocrine carcinomas (H-Apo) display transcriptomic signs of active androgen metabolism and fewer DNA lesions than others molecular apocrine tumors. This could suggest that molecular apocrine and H-apocrine tumor derive from the same cell of origin, but that only H-Apo retains morphological apocrine features, possibly due to the presence of fewer genetic lesions. In any case, the prominent androgen signaling activation warrants functional assays of anti-androgen in these breast cancer subtypes.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-05-01.

P1-12-01: Pregnancy during and Following Adjuvant Trastuzumab in Patients with HER2−Positive Breast Cancer: An Analysis from the HERA Trial (BIG 01-01)

Background: 1-year of adjuvant trastuzumab (T) is the standard of care in managing patients (pts) with early HER2−positive breast cancer (BC). As T is not known to alter fertility, pts with childbearing potential could become pregnant during or following treatment with T. Cases of oligohydramnios, some associated with fatal pulmonary hypoplasia of the fetus have been reported in women receiving T during pregnancy (preg). Here we report the outcome of preg in all pts enrolled in the HERA trial.

Methods: Pregnancies in the HERA trial are reported on a distinct “pregnancy form” for up to 10 years following T completion. The form includes information on approximate date of conception, preg course & outcome, fetal measurements at birth, and congenital anomalies. Any missing data were retrieved from the study site, if available. For this analysis, pts were grouped into 3 groups: 1) preg during and up to 3 months after T, 2) preg &gt; 3 months of last T dose, and 3) preg with no prior exposure to T.

Results: By March 2010, 70 preg were reported in 58 out of 5102 pts randomized. Five, 30 and 7 completed preg were reported in groups 1, 2 & 3 respectively.

OT1-02-04: Adjuvant Pertuzumab and Herceptin IN IniTial TherapY of Breast Cancer: APHINITY (BIG 4–11/BO25126/TOC4939g)

Background

Approximately 20% of breast cancer (BC) patients (pts) have HER2−positive tumors. While the adjuvant use of the anti-HER2 humanized monoclonal antibody trastuzumab (T) has been shown to improve disease-free (DFS) and overall survival (OS), not all pts treated with this agent benefit from this therapy. Pertuzumab (P) is a humanized monoclonal antibody that inhibits HER2 dimerization and induces ADCC with a complementary mechanism of action to T. In HER2−positiveadvanced BC, T and P is active in pts who have progressed to T. In the neoadjuvant setting, T and P in combination with chemotherapy (CT) nearly doubled the pathological complete response rate compared to either T or P administered in combination with CT (45.8% vs 29% vs 24%, respectively). Therefore, comprehensive HER2 blockade with two anti-HER2 monoclonal antibodies warrants further investigation in the adjuvant setting.

Trial Design: APHINITY is a prospective, randomized, multicenter, double-blind, placebo-controlled study in pts with HER2−positive primary BC who have had an excision of their tumor. Pts will be randomized to one of 2 arms (1:1 ratio). The investigational arm will comprise of a course of adjuvant CT (investigators choice) consisting of either an anthracycline-taxane or taxane-platin containing regimens and T and P for 1 year. The comparator arm will consist of the same adjuvant CT backbone with T and placebo for 1 year.

Major Eligibility Criteria:

1. Non-metastatic primary BC histologically confirmed and adequately excised

2. Node-positive or node-negative: for patients with node-positive disease (pN ≥1), any pT except T0; for patients with node-negative disease (pN0), tumor size must be &gt;1.0 cm OR for tumor size between &gt;0.5 cm and ≤1.0 cm, at least one of the following features will be required: histologic grade 3 OR negative for ER and PgR OR age &lt;35 years

3. The interval between definitive surgery for BC and randomization must be at least 3 weeks but no more than 7 weeks

4. Baseline LVEF ≥55%

5. HER2−positive BC confirmed by a central laboratory and defined as: IHC 3+ in &gt;10% immunoreactive cells OR HER2 gene amplification by in situ hybridization [ISH] (ratio of HER2 gene signals to centromere 17 signals ≥2)

Aims: The primary objective is to compare invasive disease-free survival (IDFS) between both treatment arms. Secondary objectives include comparing IDFS including second non-BC, DFS, OS, recurrence-free interval (RFI), distant RFI, cardiac safety, overall safety and health-related quality of life in the two treatment arms.

Statistical Methods: Pts will be stratified based on nodal status, type of adjuvant CT regimen, hormone receptor status and geographical region. The study is designed to have an 80% power to test the null hypothesis of no true difference in risk of an IDFS event (HR = 1) versus the alternative hypothesis of a difference (HR = 0.75) in hazard rates with a 5%, 2-sided significance level.

Target accrual: 3806; Present accrual: Start Q4 2011

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr OT1-02-04.

Phase IIb double-blind, randomized, placebo-controlled trials for the efficacy and safety of sorafenib in patients (pts) with metastatic or locally advanced breast cancer (BC): Review of the Trials to Investigate the Effects of Sorafenib in BC (TIES) program

e12000

Sorafenib is a potent multikinase inhibitor approved by the FDA and EMEA for the treatment of advanced renal cell carcinoma and hepatocellular carcinoma. As a single agent, sorafenib has been shown to have activity in pts with BC. Here, we review the TIES program, a compilation of currently ongoing investigator-sponsored phase IIb multinational, randomized, double-blind, placebo-controlled studies that aim to determine the optimal sequencing of pharmacologic agents for the treatment of BC. All studies will combine sorafenib with first- and/or second-line chemotherapy and/or hormonal therapy in pts with HER2-negative metastatic or locally advanced BC, enroll 220 pts, stratify pts by visceral vs nonvisceral disease, allow pts with evaluable and measurable disease, and include pts with treated brain metastases. The primary endpoint of all trials will be progression-free survival. Secondary endpoints will be safety, overall survival, objective response rate, duration of response, and time to progression. Some studies will also assess quality of life, pharmacokinetic sampling, and biomarkers. Additional information on four of the trials is shown below (Table). Patient characteristics and accruals will be reported.

[Table: see text]

No significant financial relationships to disclose.

Assessment of trastuzumab-related cardiac dysfunction in the Herceptin Adjuvant (HERA) Trial with 3.6 years median follow- up

540

Background: The Herceptin Adjuvant (HERA) Trial is a three-group randomized trial that compared 1 year or 2 years trastuzumab with observation. We investigated cardiac dysfunction in HERA patients randomized to observation or 1 year trastuzumab and report results at a median follow-up of 3.6 years. Methods: Only patients who after completion of (neo)adjuvant chemotherapy with or without radiotherapy had normal left ventricular ejection fraction (LVEF > 55%) were eligible. Cardiac function was monitored throughout the trial. A repeat LVEF assessment was required in case of cardiac dysfunction. Results: There were 1,698 patients randomized to observation and 1,703 randomized to 1 year trastuzumab. The incidence of discontinuation of trastuzumab due to cardiac disorders was low (5.1%). The incidence of cardiac endpoints was low (severe CHF 0.77% in the trastuzumab group). The incidence of cardiac endpoints was higher in the trastuzumab group compared to observation (severe CHF 0.77% vs 0.00%; confirmed significant LVEF drops 3.57% vs 0.64%). In the trastuzumab group, there were no occurrences of severe CHF after the end of the scheduled treatment period of 1 year. Among the patients in the trastuzumab group with confirmed significant LVEF drop, the first occurrence was within the scheduled treatment period of 1 year for 55 out of 60 patients (91.7%). In the trastuzumab group, 59 of 73 patients (80.8%) with a cardiac endpoint reached acute recovery and of these 59 patients 52 (88.1%) were consider to have a favourable long term outcome. Conclusions: The incidence of cardiac endpoints remains low even with longer term follow-up. The cumulative incidence of any type of cardiac endpoint increases during the scheduled treatment period of 1 year, but appears to remain approximately constant after the scheduled treatment period of 1 year is completed.

[Table: see text]

Is risk of central nervous system (CNS) relapse related to adjuvant taxane treatment in node-positive breast cancer? Results of the CNS substudy in the intergroup Phase III BIG 02-98 Trial

BACKGROUND

Breast cancer central nervous system (CNS) metastases are an increasingly important problem because of high CNS relapse rates in patients treated with trastuzumab and/or taxanes.

PATIENTS AND METHODS

We evaluated data from 2887 node-positive breast cancer patients randomised in the BIG 02-98 trial comparing anthracycline-based adjuvant chemotherapy (control arms) to anthracycline-docetaxel-based sequential or concurrent chemotherapy (experimental arms). After a median follow-up of 5 years, 403 patients had died and detailed information on CNS relapse was collected for these patients.

RESULTS

CNS relapse occurred in 4.0% of control patients and 3.7% of docetaxel-treated patients. CNS relapse occurred in 27% of deceased patients in both treatment groups. CNS relapse was usually accompanied by neurologic symptoms (90%), and 25% of patients with CNS relapse died without evidence of extra-CNS relapse. Only 20% of patients survived 1 year from the diagnosis of CNS relapse. Prognosis of CNS relapse was worse for patients with meningeal carcinomatosis when compared with brain metastases. Unexpected findings included a higher rate of positive cerebrospinal fluid cytology (8% versus 3%) and more frequent use of magnetic resonance imaging for diagnosis (47% versus 30%) in the docetaxel-treated patients.

CONCLUSION

There is no evidence that adjuvant docetaxel treatment is associated with an increased frequency of CNS relapse.

HER-2 overexpression/amplification and its interaction with taxane-based therapy in breast cancer

Breast cancer (BC) is the most common cancer in women and it is incurable when metastases are diagnosed. Taxanes, namely docetaxel and paclitaxel, are effective chemotherapeutic agents in the metastatic, neoadjuvant and adjuvant settings. HER-2 overexpression/amplification is detected in 25-30% of BCs and confers aggressive tumor behavior as well as resistance to some systemic treatments; nevertheless, its association with response to taxane-based chemotherapy is still unclear, with conflicting results in both in vitro and in vivo preclinical studies. This review will address the impact of HER-2 overexpression/amplification in BC patients treated with taxanes. Prospective, randomized trials incorporating important biological hypotheses are either ongoing or just closed, and their results will hopefully help to shed more light on this issue.

Phase III trial comparing two dose levels of epirubicin combined with cyclophosphamide (EC or HEC) with cyclophosphamide, methotrexate, and fluorouracil (CMF) in 777 women with node-positive (N+) breast cancer (BC): 10-year follow-up results

568

Background: The purpose of this presentation is to provide an update, with longer follow up data, of the results of this Belgian multicentric trial, which had shown a dose response curve for epirubicin at a median follow up of 4 years (Piccart et al, J Clin Oncol 2001; 19:3103–3110) Methods: In this prospective, open label, randomized trial of the 1990’s, patients aged from 18 to 70 years were stratified by center, 1–3 vs 4 or more nodes, and menopausal status (pre- vs postmenopausal). The primary hypothesis was that HEC could be associated with an increase in event-free survival (EFS) compared with CMF. Patients received CMF (oral cyclophosphamide days 1–14) for six cycles, EC (epirubicin 60 mg/m2, cyclophosphamide 500 mg/m2 day 1 every 3 weeks) for eight cycles or HEC (epirubicin 100 mg/m2, cyclophosphamide 830 mg/m2 day 1 every 3 weeks) for eight cycles. Tamoxifen followed chemotherapy in postmenopausal women with positive or unknown hormone receptor (HR). Two hundred fifty-five, 267, and 255 eligible patients were treated with CMF, EC, and HEC, respectively. Results: The trial results are now updated, with an actuarial median follow-up of 12.2 years. Using Kaplan-Meier estimation, the 10-year EFS is 55% for patients who received CMF, 48% for EC patients, and 58% for HEC patients. The hazard ratios obtained from Cox regression models (HR) are, for EC vs HEC, 1.30 (95% confidence interval [CI], 1.02 to 1.67, P = .03); for CMF vs HEC, 1.12 (95% CI, 0.87 to 1.44, P = .39); and for CMF vs EC, 1.17 (95% CI, 0.92 to 1.48, P = .21). Kaplan-Meier estimates of the 10-year overall survival rates are 65% for patients who received CMF, 65% for EC patients, and 70% for HEC patients, with no significant differences among the three arms. Conclusions: The short term results of this trial are nicely confirmed at 10 years: in patients unselected for HR or HER-2 status, the dose intensity of epirubicin matters. Analysis in subsets of patients is ongoing, but will be only hypothesis-generating.

[Table: see text]

[Breast cancer treatment in 2004: towards a tailored approach]

Breast cancer remains one of the most frequent malignancies that general practitioners are confronted with. Given their key-counselling role for the affected families, they need regular updates on the multi-disciplinary management of the disease. This has been characterized by an evolution towards less aggressive surgery, sparing many women the morbidity of a full axillary node dissection; in parallel, there is increasing hope for "individualized" adjuvant medical treatment, given the development of new technologies that provide an "identity card" of the genes expressed by each tumour. These technologies should improve our ability to identify which women truly need adjuvant chemotherapy and to select the best medical treatment on an individual basis. While providing these messages of hope, this chapter also reviews the major classes of drugs used for the treatment of advanced breast cancer.

What can be expected from the next generation of adjuvant breast cancer treatment?

At present, the adjuvant therapy of breast cancer is the only treatment that offers the prospect of cure. However, recent meta-analysis has shown that although they are statistically significant, the benefits that accompany existing adjuvant chemotherapy or endocrine therapy are modest. Hence, there is a pressing need to evaluate the contribution of active new agents such as the taxanes in the adjuvant setting. A further challenge is to integrate entirely new treatment strategies targeting signal transduction, apoptosis, and angiogenesis with existing treatments. Progress also is being made in the identification of molecular markers, such as overexpression of the c-erbB2 receptor, which may influence the selection of adjuvant therapy to be given to those patients at greatest risk from their breast cancer. Success in all these areas requires rigorously conducted clinical trials. These will be conducted efficiently and rapidly only if there is good collaboration between investigators, such as is now being expected from the recently created Breast International Group.