Survival after adding capecitabine and trastuzumab to neoadjuvant anthracycline-taxane-based chemotherapy for primary breast cancer (GBG 40--GeparQuattro)

An Analysis of PIK3CA Hotspot Mutations and Response to Neoadjuvant Therapy in Patients with Breast Cancer from Four Prospective Clinical Trials

PURPOSE

The PI3K signaling pathway is frequently dysregulated in breast cancer, and mutations in PIK3CA are relevant for therapy resistance in HER2-positive (HER2pos) breast cancer. Mutations in exons 9 or 20 may have different impacts on response to neoadjuvant chemotherapy-based treatment regimens.

EXPERIMENTAL DESIGN

We investigated PIK3CA mutations in 1,691 patients with early breast cancer who were randomized into four neoadjuvant multicenter trials: GeparQuattro (NCT00288002), GeparQuinto (NCT00567554), GeparSixto (NCT01426880), and GeparSepto (NCT01583426). The role of different PIK3CA exons and hotspots for pathologic complete response (pCR) following neoadjuvant chemotherapy (NACT) and patient survival were evaluated for distinct molecular subgroups and anti-HER2 treatment procedures.

RESULTS

A total of 302 patients (17.9%) of the full cohort of 1,691 patients had a tumor with a PIK3CA mutation, with a different prevalence in molecular subgroups: luminal/HER2-negative (HER2neg) 95 of 404 (23.5%), HER2pos 170 of 819 (20.8%), and triple-negative breast cancer 37 of 468 patients (7.9%). We identified the mutations in PIK3CA exon 20 to be linked with worse response to anti-HER2 treatment (OR = 0.507; 95% confidence interval, 0.320-0.802; P = 0.004), especially in hormone receptor-positive HER2-positive breast cancer (OR = 0.445; 95% confidence interval, 0.237-0.837; P = 0.012). In contrast, exon 9 hotspot mutations p.E452K and p.E545K revealed no noteworthy differences in response therapy. Luminal/HER2neg patients show a trend to have worse treatment response when PIK3CA was mutated. Interestingly, patients with residual disease following neoadjuvant treatment had better survival rates when PIK3CA was mutated.

CONCLUSIONS

The PIK3CA hotspot mutation p.H1047R is associated with worse pCR rates following NACT in HER2pos breast cancer, whereas hotspot mutations in exon 9 seem to have less impact.

Differential response of HER2-positive breast cancer to anti-HER2 therapy based on HER2 protein expression level

BACKGROUND

Increasing data indicate that HER2-positive (HER2 + ) breast cancer (BC) subtypes exhibit differential responses to targeted anti-HER2 therapy. This study aims to investigate these differences and the potential underlying molecular mechanisms.

METHODS

A large cohort of BC patients (n = 7390) was utilised. The clinicopathological characteristics and differential gene expression (DGE) of HER2+ immunohistochemical (IHC) subtypes, specifically HER2 IHC 3+ and IHC 2 + /Amplified, were assessed and correlated with pathological complete response (pCR) and survival in the neoadjuvant and adjuvant settings, respectively. The role of oestrogen receptor (ER) status was also investigated.

RESULTS

Compared to HER2 IHC 3+ tumours, BC patients with IHC 2 + /Amplified showed a significantly lower pCR rate (22% versus 57%, P < 0.001), shorter survival regardless of HER2 gene copy number, were less classified as HER2 enriched, and enriched for trastuzumab resistance and ER signalling pathway genes. ER positivity significantly decreased response to anti-HER2 therapy in IHC 2 + /Amplified, but not in IHC 3 + BC patients.

CONCLUSION

In HER2 + BC, overexpression of HER2 protein is the driver of the oncogenic pathway, and it is the main predictor of response to anti-HER2 therapy. ER signalling pathways are more dominant in BC with equivocal HER2 expression. personalised anti-HER2 therapy based on IHC classes should be considered.

Identifying breast cancer patients at risk of relapse despite pathological complete response after neoadjuvant therapy

This retrospective pooled analysis aims to identify factors predicting relapse despite a pathologic complete response (pCR) in patients with breast cancer (BC). 2066 patients with a pCR from five neoadjuvant GBG/AGO-B trials fulfill the inclusion criteria of this analysis. Primary endpoint is disease-free survival (DFS); secondary endpoints is distant DFS (DDFS) and overall survival (OS). After a median follow-up of 57.6 months, DFS is significantly worse for patients with positive lymph nodes (cN+ vs cN0 hazard ratio [HR] 1.94, 95%CI 1.48-2.54; p < 0.001). In patients with triple-negative tumors, lobular histology (lobular vs other HR 3.55, 95%CI 1.53-8.23; p = 0.003), and clinical nodal involvement (cN+ vs cN0 HR 2.45, 95%CI 1.59-3.79; p < 0.001) predict a higher risk of DFS events. Patients with HER2-positive cT3/4 tumors have a significantly higher risk of relapse (cT3/4 vs cT1 HR 2.07, 95%CI 1.06-4.03; p = 0.033). Initial tumor load and histological type predict relapse in patients with a pCR.

Three-year disease-free survival in randomized trials of neoadjuvant chemotherapy and HER2-targeted therapy in breast cancer: A meta-analysis

BACKGROUND

Outcomes for breast cancer patients with residual disease (RD) after neoadjuvant chemotherapy (NACT) and HER2-targeted therapy may be better than anticipated leading to a smaller absolute benefit of adjuvant trastuzumab emtansine (T-DM1). Therefore, accurate estimates of 3-year disease-free survival (DFS) can aid in treatment planning.

METHODS

We reviewed randomized trials of NACT and HER2-targeted therapy in breast cancer (excluding T-DM1) and calculated mean 3-year DFS weighted by study sample size. Meta-regression comprising linear regression weighted by sample size (mixed-effects) was performed to explore associations between 3-year DFS and year of accrual and trial-level patient, disease, and treatment factors. Data were reported quantitatively irrespective of statistical significance.

RESULTS

Eleven studies (N = 3581) were included in the primary analysis. The mean 3-year DFS for patients with RD was 79.7% (95% CI 77.4-80.9). This was higher for trials completing accrual after 2010 [83% (95% CI 79.3-86.3)] and for those receiving dual HER2 targeted therapy [83.4% (95% CI 79.2-87.7]. Better outcomes for ER positivity, later accrual and dual Her-2 targeted therapy were confirmed in meta-regression. Negative quantitative significance was observed for larger clinical tumor size and nodal involvement.

CONCLUSIONS

The 3-year DFS for patients with RD has improved over time possibly due to dual HER2 targeted therapy. This will reduce the absolute benefit of adjuvant T-DM1 in this group of patients.

Efficacy analysis of neoadjuvant chemotherapy with or without anthracyclines in female patients with HER2-positive breast cancer in China: a nationwide, multicenter, 10-year retrospective study (CSBrS-012)

Background

In the era of targeted therapy, whether patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer are exempted from anthracycline usage in the neoadjuvant setting is controversial.

Objectives

Our objective was to retrospectively analyze the differences in pathological complete remission (pCR) rates between the anthracycline group and the nonanthracycline group.

Design

The CSBrS-012 study (2010-2020) included female primary breast cancer patients with neoadjuvant chemotherapy (NAC) who underwent standard breast and axillary surgery post-NAC.

Methods

A logistic proportional hazard model was applied to estimate the association of covariates with pCR. Propensity score matching (PSM) was performed to balance the differences in baseline characteristics, and subgroup analyses were performed using the Cochran-Mantel-Haenszel test.

Results

A total of 2507 patients were enrolled: the anthracycline group (n = 1581, 63%) and the nonanthracycline group (n = 926, 37%). A pCR was recorded in 17.1% (271/1581) of patients in the anthracycline group and in 29.3% (271/926) in the nonanthracycline group, and the difference in the pCR rate between the two groups was statistically significant [odds ratio (OR) = 2.00, 95% confidence interval (CI) (1.65-2.43); p < 0.001). In the subsequent subgroup analysis, substantial differences in pCR rates between the anthracycline and nonanthracycline groups were detected in the nontargeted [OR = 1.91, 95% CI (1.13-3.23); p = 0.015] and dual-HER2-targeted populations [OR = 0.55, 95% CI (0.33-0.92); p = 0.021) before PSM, whereas differences vanished after PSM. The pCR rates between the anthracycline and nonanthracycline groups did not differ for the single target population, either before or after PSM.

Conclusion

In the presence of trastuzumab and/or pertuzumab, the pCR rate of patients with HER2-positive breast cancer receiving anthracycline was not superior to that of patients receiving nonanthracycline. Thus, our study further provides clinical evidence for exempting anthracycline treatment in HER2-positive breast cancer in the era of targeted therapy.

Neoadjuvant docetaxel and capecitabine (TX) versus docetaxel and epirubicin (TE) for locally advanced or early her2-negative breast cancer: an open-label, randomized, multi-center, phase II Trial

PURPOSE

The combination of taxanes and anthracyclines is still the mainstay of chemotherapy for early breast cancer. Capecitabine is an active drug with a favorable toxicity profile, showing strong anti-tumor activity against metastatic breast cancer. This trial assessed the efficacy and safety of the TX regimen (docetaxel and capecitabine) and compared it with the TE (docetaxel and epirubicin) regimen in locally advanced or high risk early HER2-negative breast cancer.

PATIENTS AND METHODS

This randomized clinical trial was conducted at five academic centers in China. Eligible female patients were randomly assigned (1:1) to the TX (docetaxel 75 mg/m² d1 plus capecitabine 1000 mg/m² twice d1-14, q3w) or TE (docetaxel 75 mg/m² d1 plus epirubicin 75 mg/m² d1, q3w) groups for four cycles. The primary endpoint was a pathological complete response in the breast (pCR). Secondary endpoints included pCR in the breast and axilla, invasive disease-free survival (iDFS), overall survival (OS), and safety.

RESULTS

Between September 1, 2012, and December 31, 2018, 113 HER2-negative patients were randomly assigned to the study groups (TX: n = 54; TE: n = 59). In the primary endpoint analysis, 14 patients in the TX group achieved a pCR, and nine patients in the TE group achieved a pCR (25.9% vs. 15.3%), with a not significant difference of 10.6% (95% CI -6.0-27.3%; P = 0.241). In a subgroup with high Ki-67 score, TX increased the pCR rate by 24.2% (95% CI 2.2-46.1%; P = 0.029). At the end of the 69-month median follow-up period, both groups had equivalent iDFS and OS rates. TX was associated with a higher incidence of hand-foot syndrome and less alopecia, with a manageable toxicity profile.

CONCLUSION

The anthracycline-free TX regimen yielded comparable pCR and long-term survival rates to the TE regimen. Thus, this anthracycline-free regimen could be considered in selected patients.

TRIAL REGISTRATION

ACTRN12613000206729 on 21/02/2013, retrospectively registered.

Evaluation of pathological complete response as surrogate endpoint in neoadjuvant randomised clinical trials of early stage breast cancer: systematic review and meta-analysis

OBJECTIVE

To evaluate pathological complete response as a surrogate endpoint for disease-free survival and overall survival in regulatory neoadjuvant trials of early stage breast cancer.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Medline, Embase, and Scopus to 1 December 2020.

ELIGIBILITY CRITERIA FOR STUDY SELECTION

Randomised clinical trials that tested neoadjuvant chemotherapy given alone or combined with other treatments, including anti-human epidermal growth factor 2 (anti-HER2) drugs, targeted treatments, antivascular agents, bisphosphonates, and immune checkpoint inhibitors.

DATA EXTRACTION AND SYNTHESIS

Trial level associations between the surrogate endpoint pathological complete response and disease-free survival and overall survival.

METHODS

A weighted regression analysis was performed on log transformed treatment effect estimates (hazard ratio for disease-free survival and overall survival and relative risk for pathological complete response), and the coefficient of determination (R2) was used to quantify the association. The secondary objective was to explore heterogeneity of results in preplanned subgroups analysis, stratifying trials according treatment type in the experimental arm, definition used for pathological complete response (breast and lymph nodes v breast only), and biological features of the disease (HER2 positive or triple negative breast cancer). The surrogate threshold effect was also evaluated, indicating the minimum value of the relative risk for pathological complete response necessary to confidently predict a non-null effect on hazard ratio for disease-free survival or overall survival.

RESULTS

54 randomised clinical trials comprising a total of 32 611 patients were included in the analysis. A weak association was observed between the log(relative risk) for pathological complete response and log(hazard ratio) for both disease-free survival (R2=0.14, 95% confidence interval 0.00 to 0.29) and overall survival (R2 =0.08, 0.00 to 0.22). Similar results were found across all subgroups evaluated, independently of the definition used for pathological complete response, treatment type in the experimental arm, and biological features of the disease. The surrogate threshold effect was 5.19 for disease-free survival but was not estimable for overall survival. Consistent results were confirmed in three sensitivity analyses: excluding small trials (<200 patients enrolled), excluding trials with short median follow-up (<24 months), and replacing the relative risk for pathological complete response with the absolute difference of pathological complete response rates between treatment arms.

CONCLUSION

A lack of surrogacy of pathological complete response was identified at trial level for both disease-free survival and overall survival. The findings suggest that pathological complete response should not be used as primary endpoint in regulatory neoadjuvant trials of early stage breast cancer.

Treatment landscape of triple-negative breast cancer - expanded options, evolving needs

Tumour heterogeneity and a long-standing paucity of effective therapies other than chemotherapy have contributed to triple-negative breast cancer (TNBC) being the subtype with the least favourable outcomes. In the past few years, advances in omics technologies have shed light on the relevance of the TNBC microenvironment heterogeneity, unveiling a close dynamic relationship with cancer cell features. An improved understanding of tumour-immune system co-evolution supports the need to adopt a more comprehensive view of TNBC as an ecosystem that encompasses the intrinsic and extrinsic features of cancer cells. This new appreciation of the biology of TNBC has already led to the development of novel targeted agents, including PARP inhibitors, antibody-drug conjugates and immune-checkpoint inhibitors, which are revolutionizing the therapeutic landscape and providing new opportunities both for patients with early-stage TNBC and for those with advanced-stage disease. The current therapeutic scenario is only the tip of the iceberg, as hundreds of new compounds and combinations are in development. The translation of these experimental therapies into clinical benefit is a welcome and ongoing challenge. In this Review, we describe the current and upcoming therapeutic landscape of TNBC and discuss how an integrated view of the TNBC ecosystem can define different levels of risk and provide improved opportunities for tailoring treatment.

Additional adjuvant capecitabine in early breast cancer patients: a meta-analysis of randomized controlled trials

Aims: To assess the efficacy and safety of adjuvant capecitabine in early breast cancer patients. Methods: A literature search of databases was conducted to identify randomized controlled trials reporting the efficacy and toxicity of capecitabine as adjuvant therapy in early breast cancer patients. Results: Six studies were eligible and included a total of 6941 patients. Disease-free survival (hazard ratio = 0.79; 95% CI = 0.71-0.88; p < 0.0001) was significantly improved with additional capecitabine, whereas improvement in overall survival (OS) was not significant. The more pronounced benefits in both disease-free survival and OS were observed among triple-negative breast cancer patients. Conclusion: Additional capecitabine in the adjuvant setting conferred substantial disease-free survival benefit and a tendency toward improved OS. Triple-negative breast cancer patients can benefit from capecitabine irrespective of the administration sequence. Capecitabine may be considered a preferred additional treatment for early-stage triple-negative breast cancer patients, and sequential capecitabine can serve as an alternative choice for patients with poor tolerance.

MINImal vs. MAXimal Invasive Axillary Staging and Treatment After Neoadjuvant Systemic Therapy in Node Positive Breast Cancer: Protocol of a Dutch Multicenter Registry Study (MINIMAX)

BACKGROUND

Node positive breast cancer (cN+) patients with an axillary pathologic complete response after neoadjuvant systemic therapy (NST) are not expected to benefit from axillary lymph node dissection (ALND). Therefore, less invasive axillary staging procedures have been introduced to establish response-guided treatment. However, evidence is lacking with regard to their oncologic safety and impact on quality of life (QoL). We hypothesize that if response-guided treatment is given, less invasive staging procedures are non-inferior to standard ALND in terms of oncologic safety, and superior to standard ALND in terms of QoL.

PATIENTS AND METHODS

MINIMAX is a Dutch multicenter registry study that includes patients with cN1-3M0 unilateral invasive breast cancer, who receive NST, followed by axillary staging and treatment according to local protocols. In a retrospective registry of ±4000 patients, the primary endpoint is oncologic safety at 5 and 10 years (disease-free, breast-cancer-specific and overall survival, and axillary recurrence rate). In a prospective multicenter registry, the primary endpoints are QoL at 1 and 5 years, and we aim to verify the 5-year oncologic safety. With an estimated 5-year disease-free survival of 72.5% and anticipated loss to follow-up of 10%, a sample size of 549 is needed to have 80% power to detect non-inferiority (with a 10% margin) of less invasive staging procedures.

CONCLUSION

In cN+ patients treated with NST, less invasive axillary staging procedures are already implemented globally. Evidence is needed to support the assumed oncologic safety and superior QoL of such procedures. This study will contribute to evidence-based guidelines.

Capecitabine for hormone receptor-positive versus hormone receptor-negative breast cancer

BACKGROUND

Retrospective analyses suggest that capecitabine may carry superior activity in hormone receptor-positive relative to hormone receptor-negative metastatic breast cancer. This review examined the veracity of that finding and explored whether this differential activity extends to early breast cancer.

OBJECTIVES

To assess effects of chemotherapy regimens containing capecitabine compared with regimens not containing capecitabine for women with hormone receptor-positive versus hormone receptor-negative breast cancer across the three major treatment scenarios: neoadjuvant, adjuvant, metastatic.

SEARCH METHODS

On 4 June 2019, we searched the Cochrane Breast Cancer Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL; 2019, Issue 5) in the Cochrane Library; MEDLINE; Embase; the World Health Organization International Clinical Trials Registry Platform; and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials looking at chemotherapy regimens containing capecitabine alone or in combination with other agents versus a control or similar regimen without capecitabine for treatment of breast cancer at any stage. The primary outcome measure for metastatic and adjuvant trials was overall survival (OS), and for neoadjuvant studies pathological complete response (pCR).

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed risk of bias and certainty of evidence using the GRADE approach. Hazard ratios (HRs) were derived for time-to-event outcomes, and odds ratios (ORs) for dichotomous outcomes, and meta-analysis was performed using a fixed-effect model.

MAIN RESULTS

We included 26 studies with outcome data by hormone receptor: 12 metastatic studies (n = 4325), 6 neoadjuvant trials (n = 3152), and 8 adjuvant studies (n = 13,457). Capecitabine treatment was added in several different ways across studies. These could be classified as capecitabine alone compared to another treatment, capecitabine substituted for part of the control chemotherapy, and capecitabine added to control chemotherapy. In the metastatic setting, the effect of capecitabine was heterogenous between hormone receptor-positive and -negative tumours. For OS, no difference between capecitabine-containing and non-capecitabine-containing regimens was observed for all participants taken together (HR 1.01, 95% confidence interval (CI) 0.98 to 1.05; 12 studies, 4325 participants; high-certainty evidence), for those with hormone receptor-positive disease (HR 0.93, 95% CI 0.84 to 1.04; 7 studies, 1834 participants; high-certainty evidence), and for those with hormone receptor-negative disease (HR 1.00, 95% CI 0.88 to 1.13; 8 studies, 1577 participants; high-certainty evidence). For progression-free survival (PFS), a small improvement was seen for all people (HR 0.89, 95% CI 0.82 to 0.96; 12 studies, 4325 participants; moderate-certainty evidence). This was largely accounted for by a moderate improvement in PFS for inclusion of capecitabine in hormone receptor-positive cancers (HR 0.82, 95% CI 0.73 to 0.91; 7 studies, 1594 participants; moderate-certainty evidence) compared to no difference in PFS for hormone receptor-negative cancers (HR 0.96, 95% CI 0.83 to 1.10; 7 studies, 1122 participants; moderate-certainty evidence). Quality of life was assessed in five studies; in general there did not seem to be differences in global health scores between the two treatment groups at around two years' follow-up. Neoadjuvant studies were highly variable in design, having been undertaken to test various experimental regimens using pathological complete response (pCR) as a surrogate for disease-free survival (DFS) and OS. Across all patients, capecitabine-containing regimens resulted in little difference in pCR in comparison to non-capecitabine-containing regimens (odds ratio (OR) 1.12, 95% CI 0.94 to 1.33; 6 studies, 3152 participants; high-certainty evidence). By subtype, no difference in pCR was observed for either hormone receptor-positive (OR 1.22, 95% CI 0.76 to 1.95; 4 studies, 964 participants; moderate-certainty evidence) or hormone receptor-negative tumours (OR 1.28, 95% CI 0.61 to 2.66; 4 studies, 646 participants; moderate-certainty evidence). Four studies with 2460 people reported longer-term outcomes: these investigators detected no difference in either DFS (HR 1.02, 95% CI 0.86 to 1.21; high-certainty evidence) or OS (HR 0.97, 95% CI 0.77 to 1.23; high-certainty evidence). In the adjuvant setting, a modest improvement in OS was observed across all participants (HR 0.89, 95% CI 0.81 to 0.98; 8 studies, 13,547 participants; moderate-certainty evidence), and no difference in OS was seen in hormone receptor-positive cancers (HR 0.86, 95% CI 0.68 to 1.09; 3 studies, 3683 participants), whereas OS improved in hormone receptor-negative cancers (HR 0.72, 95% CI 0.59 to 0.89; 5 studies, 3432 participants). No difference in DFS or relapse-free survival (RFS) was observed across all participants (HR 0.93, 95% CI 0.86 to 1.01; 8 studies, 13,457 participants; moderate-certainty evidence). As was observed for OS, no difference in DFS/RFS was seen in hormone receptor-positive cancers (HR 1.03, 95% CI 0.91 to 1.17; 5 studies, 5604 participants; moderate-certainty evidence), and improvements in DFS/RFS with inclusion of capecitabine were observed for hormone receptor-negative cancers (HR 0.74, 95% CI 0.64 to 0.86; 7 studies, 3307 participants; moderate-certainty evidence). Adverse effects were reported across all three scenarios. When grade 3 or 4 febrile neutropenia was considered, no difference was seen for capecitabine compared to non-capecitabine regimens in neoadjuvant studies (OR 1.31, 95% CI 0.97 to 1.77; 4 studies, 2890 participants; moderate-certainty evidence), and a marked reduction was seen for capecitabine in adjuvant studies (OR 0.55, 95% CI 0.47 to 0.64; 5 studies, 8086 participants; moderate-certainty evidence). There was an increase in diarrhoea and hand-foot syndrome in neoadjuvant (diarrhoea: OR 1.95, 95% CI 1.32 to 2.89; 3 studies, 2686 participants; hand-foot syndrome: OR 6.77, 95% CI 4.89 to 9.38; 5 studies, 3021 participants; both moderate-certainty evidence) and adjuvant trials (diarrhoea: OR 2.46, 95% CI 2.01 to 3.01; hand-foot syndrome: OR 13.60, 95% CI 10.65 to 17.37; 8 studies, 11,207 participants; moderate-certainty evidence for both outcomes).

AUTHORS' CONCLUSIONS

In summary, a moderate PFS benefit by including capecitabine was seen only in hormone receptor-positive cancers in metastatic studies. No benefit of capecitabine for pCR was noted overall or in hormone receptor subgroups when included in neoadjuvant therapy. In contrast, the addition of capecitabine in the adjuvant setting led to improved outcomes for OS and DFS in hormone receptor-negative cancer. Future studies should stratify by hormone receptor and triple-negative breast cancer (TNBC) status to clarify the differential effects of capecitabine in these subgroups across all treatment scenarios, to optimally guide capecitabine inclusion.

KRT20, KRT5, ESR1 and ERBB2 Expression Can Predict Pathologic Outcome in Patients Undergoing Neoadjuvant Chemotherapy and Radical Cystectomy for Muscle-Invasive Bladder Cancer

Patients with muscle-invasive bladder cancer (MIBC) that underwent neoadjuvant chemotherapy (NAC) prior to radical cystectomy (RC) show improved overall survival, especially those with pathological complete response (pCR). The response to NAC according to molecular subtypes has been discussed. Molecular targets such as estrogen receptor (ESR1) and human epidermal growth factor receptor 2 (ERBB2) play an important role in breast cancer management and have also been associated with urothelial bladder cancer. Hence, the association of Keratin 20 (KRT20) Keratin 5 (KRT5), ESR1, and ERBB2 mRNA expression in MIBC at transurethral resection (TUR-BT) with pCR after NAC was analyzed retrospectively. Formalin-fixed paraffin-embedded tumour tissue samples from TUR-BT of 54 patients (42 males, 12 females, median age of 64) with MIBC were analyzed for KRT20, KRT5, ESR1, and ERBB2 mRNA expression. After NAC, RC was performed, and the specimens were evaluated for pCR. Statistical analyses comprised nonparametric and chi² testing, partition models, and Spearman correlation analyses. After NAC, 22 out of 54 patients (40.7%) had pCR. Tumours with an elevated expression of markers associated with luminal differentiation (KRT20, ERBB2, ESR1) were associated with a higher chance of pCR (55% vs. 15.8%, p = 0.009). Elevated ERBB2 expression was positively correlated with luminal expression features such as KRT20, and negatively with basal characteristics such as KRT5. Patients with MIBC showing a high expression of ERBB2, ESR1, or KRT20 have a significantly higher chance of pCR following NAC. These findings might improve patient selection for NAC in MIBC.

Neoadjuvant Chemotherapy, Endocrine Therapy, and Targeted Therapy for Breast Cancer: ASCO Guideline

PURPOSE

To develop guideline recommendations concerning optimal neoadjuvant therapy for breast cancer.

METHODS

ASCO convened an Expert Panel to conduct a systematic review of the literature on neoadjuvant therapy for breast cancer and provide recommended care options.

RESULTS

A total of 41 articles met eligibility criteria and form the evidentiary basis for the guideline recommendations.

RECOMMENDATIONS

Patients undergoing neoadjuvant therapy should be managed by a multidisciplinary care team. Appropriate candidates for neoadjuvant therapy include patients with inflammatory breast cancer and those in whom residual disease may prompt a change in therapy. Neoadjuvant therapy can also be used to reduce the extent of local therapy or reduce delays in initiating therapy. Although tumor histology, grade, stage, and estrogen, progesterone, and human epidermal growth factor receptor 2 (HER2) expression should routinely be used to guide clinical decisions, there is insufficient evidence to support the use of other markers or genomic profiles. Patients with triple-negative breast cancer (TNBC) who have clinically node-positive and/or at least T1c disease should be offered an anthracycline- and taxane-containing regimen; those with cT1a or cT1bN0 TNBC should not routinely be offered neoadjuvant therapy. Carboplatin may be offered to patients with TNBC to increase pathologic complete response. There is currently insufficient evidence to support adding immune checkpoint inhibitors to standard chemotherapy. In patients with hormone receptor (HR)-positive (HR-positive), HER2-negative tumors, neoadjuvant chemotherapy can be used when a treatment decision can be made without surgical information. Among postmenopausal patients with HR-positive, HER2-negative disease, hormone therapy can be used to downstage disease. Patients with node-positive or high-risk node-negative, HER2-positive disease should be offered neoadjuvant therapy in combination with anti-HER2-positive therapy. Patients with T1aN0 and T1bN0, HER2-positive disease should not be routinely offered neoadjuvant therapy.Additional information is available at www.asco.org/breast-cancer-guidelines.

Comparison of capecitabine-based regimens with platinum-based regimens in Chinese triple-negative breast cancer patients with liver metastasis

Background

Capecitabine-based chemotherapy (CBC) presents potential value in patients with liver metastasis; platinum-based chemotherapy (PBC) has shown promising benefit in patients with triple-negative breast cancer (TNBC). For TNBC patients with liver metastasis, which treatment strategy is better remains to be further studied. The aim of this study was to report the first real-world data evaluating the efficacy and safety of PBC versus CBC in the first-line treatment in Chinese TNBC patients with liver metastasis.

Methods

TNBC patients with liver metastasis pretreated with anthracyclines/taxanes in 4 institutions of China between January 2010 and December 2019 were included. Objective response rate (ORR), overall survival, treatment pattern, and toxicity profile were assessed between PBC and CBC groups.

Results

A total of 59 TNBC patients with liver metastasis were identified. Among these, 33 were treated with PBC and 26 were treated with CBC. The ORR was higher in the CBC group than in the PBC group (57.7% versus 30.3%, P=0.035). Median overall survival was also greatly improved (19.2 versus 14.4 months, P=0.041). Docetaxel/cisplatin was more likely to be used for PBC, and paclitaxel/capecitabine was the main regimen for CBC. Multivariable Cox regression analysis indicated that CBC was an independent predictor for overall survival after adjustment for baseline factors including age, tumor size, nodal status, prior anthracyclines/taxanes use, and tumor grade (odds ratio =0.51; 95% confidence interval, 0.27-0.98; P=0.042). Adverse events were not different except gastrointestinal tract toxicities, hand-foot syndrome and hematologic toxicity.

Conclusions

For TNBC patients with liver metastasis, capecitabin-based chemotherapy might be more suitable than the platinum-based regimen in the first-line treatment, as measured by objective response rate and overall survival. Further large-scale studies are warranted.

Long-term outcomes in patients with PET-predicted poor-responsive HER2-positive breast cancer treated with neoadjuvant bevacizumab added to trastuzumab and docetaxel: 5-year follow-up of the randomised Avataxher study

BACKGROUND

The open-label, randomised Phase 2 AVATAXHER study (NCT01142778) demonstrated that early PET assessment identified HER2-positive breast cancer patients who responded poorly to neoadjuvant docetaxel plus trastuzumab. Adding neoadjuvant bevacizumab for PET-predicted poor-responders improved pathological complete response (pCR) rates (43.8% vs 24.0%). We investigated long-term study outcomes.

METHODS

Patients were treated in three groups. All patients initially received two cycles of standard neoadjuvant therapy with [¹⁸F]-FDG PET conducted before each cycle. Those with ≥70% change in the maximum standardised uptake value (∆SUVmax) received four further cycles of standard neoadjuvant therapy (PET responders). PET-predicted poor-responders (∆SUVmax <70%) were randomised (2:1) to neoadjuvant therapy with (Group A) or without (Group B) bevacizumab for cycles 3-6. All patients received one further cycle of trastuzumab before surgery plus adjuvant trastuzumab (11 cycles).

FINDINGS

142 patients were randomized and treated (PET responders, n = 69; Group A, n = 48; Group B, n = 25). 5-year disease-free survival rates were 90.5% (95% CI: 80.0-95.6%) in PET responders, 90.2% (95% CI: 75.9-96.2%) in Group A, and 76.0% (95% CI: 54.2-88.4%) in Group B. However, no difference was observed between randomised arms in a sensitivity analysis. During adjuvant therapy, the incidence of Grade ≥3 (Group A: 25.6%; Group B 12.5%) and serious adverse events (Group A: 18.6%; Group B 12.5%) was higher in Group A vs Group B, but with no apparent effect on cardiac events.

INTERPRETATION

In patients with HER2-positive breast cancer, an intervention based on early PET assessment and improvement of pCR does not modify disease-free survival.

FUNDING

Roche France.

Gemcitabine as adjuvant chemotherapy in patients with high-risk early breast cancer-results from the randomized phase III SUCCESS-A trial

Background

When chemotherapy is indicated in patients with early breast cancer, regimens that contain anthracyclines and taxanes are established standard treatments. Gemcitabine has shown promising effects on the response and prognosis in patients with metastatic breast cancer. The SUCCESS-A trial (NCT02181101) examined the addition of gemcitabine to a standard chemotherapy regimen in high-risk early breast cancer patients.

Methods

A total of 3754 patients with at least one of the following characteristics were randomly assigned to one of the two treatment arms: nodal positivity, tumor grade 3, age ≤ 35 years, tumor larger than 2 cm, or negative hormone receptor status. The treatment arms received either three cycles of 5-fluorouracil, epirubicin, and cyclophosphamide, followed by three cycles of docetaxel (FEC → Doc); or three cycles of FEC followed by three cycles of docetaxel and gemcitabine (FEC → Doc/Gem). The primary study aim was disease-free survival (DFS), and the main secondary objectives were overall survival (OS) and safety.

Results

No differences were observed in the 5-year DFS or OS between FEC → Doc and FEC → Doc/Gem. The hazard ratio was 0.93 (95% CI, 0.78 to 1.12; P = 0.47) for DFS and 0.94 (95% CI, 0.74 to 1.19; P = 0.60) for OS. For patients treated with FEC → Doc and FEC → Doc/Gem, the 5-year probabilities of DFS were 86.6% and 87.2%, and the 5-year probabilities of OS were 92.8% and 92.5%, respectively.

Conclusion

Adding gemcitabine to a standard chemotherapy does not improve the outcomes in patients with high-risk early breast cancer and should therefore not be included in the adjuvant treatment setting.

Trial registration

Clinicaltrials.gov NCT02181101 and EU Clinical Trials Register EudraCT 2005-000490-21. Registered September 2005.

Capecitabine + Epirubicin + Cyclophosphamide Combination Therapy (CEX Therapy) as Neoadjuvant Chemotherapy for HER-2-Negative Breast Cancer: A Retrospective, Single-Center Study

BACKGROUND

We modified and administered capecitabine + epirubicin + cyclophosphamide combination therapy (CEX) as neoadjuvant chemotherapy (NAC) for HER-2-negative breast cancer and retrospectively analyzed its effectiveness and tolerability at our center.

METHODS

The inclusion criteria were presence of breast cancer negative for HER-2 and positive lymph node metastasis, or negative lymph node metastasis when tumor diameter was 20 mm or greater without distant metastasis. Additional inclusion criteria were a performance status of 0 or 1, an EF >60%, and an age of 75 years or less. Clinical outcomes were evaluated after 4 courses of epirubicin 80 mg/m2, cyclophosphamide 500 mg/m2 (administered every 3 weeks), and capecitabine 1,500 mg/m2 (administered for 2 weeks and withdrawn for 1 week).

RESULTS

A clinical benefit was noted in all 18 patients who received CEX as neoadjuvant chemotherapy during the period from 2009 through 2013. The clinical response rate was 83.3% (15/18), and the clinical complete response rate was 50%. Aesthetic outcomes of breast-conserving surgery were positive in all patients. Among patients with satisfactory outcomes, 33.3% had a pathologic complete response (triple-negative: 6, luminal: 0) and 68.8% were n0 (triple-negative: 8, luminal: 3). All patients with a pathologic complete response are presently alive, free of recurrence, and currently undergoing follow-up. Adverse events were classified as grade 2 or lower in all patients.

CONCLUSIONS

CEX therapy administered as neoadjuvant chemotherapy could be useful for individualized treatment. In particular, this regimen was effective for triple-negative breast cancer.

Predictive and prognostic value of prognostic nutritional index for locally advanced breast cancer

Background

The prognostic nutritional index (PNI) is an indicator of nutritional immune status. Recently, the PNI has been found to be significantly associated with the clinical outcome of various solid tumors. Few patients with newly diagnosed breast cancer are in a state of malnutrition. In contrast, breast cancer is usually an overnutrition-related disease. This study aimed to explore the relationship of an excessively high PNI with sensitivity to neoadjuvant therapy and the prognosis of patients with locally advanced breast cancer.

Methods

A total of 202 patients from two clinical trials, SHPD002 and SHPD003, were included. Binary logistic regression analysis was used to assess the association between the PNI and pathological complete response (pCR). Univariate and multivariate survival analyses were performed to assess the prognostic factors used to predict disease-free survival (DFS).

Results

An excessively high PNI was more difficult to achieve pCR (OR =0.322; 95% CI, 0.132-0.788, P=0.013) and was associated with a worse DFS (log-rank P=0.013). The PNI was an independent prognostic factor for DFS in all patients (HR =3.027; 95% CI, 1.207-7.592, P=0.018), the premenopausal (HR =8.292; 95% CI, 1.670-41.17, P=0.010), clinical T3 and T4 (HR =3.405; 95% CI, 1.141-10.16, P=0.028), ER negative (HR =9.698; 95% CI, 1.205-78.07, P=0.033), HER2 negative (HR =3.765; 95% CI, 1.101-12.88, P=0.035) and pCR subgroups (HR =11.912; 95% CI, 1.326-107.0, P=0.027).

Conclusions

An excessively high PNI was a risk factor for sensitivity to neoadjuvant therapy and prognosis of patients with locally advanced breast cancer.

Targeted therapeutic options and future perspectives for HER2-positive breast cancer

Over the past 2 decades, there has been an extraordinary progress in the regimens developed for the treatment of human epidermal growth factor receptor 2 (HER2)-positive breast cancer. Trastuzumab, pertuzumab, lapatinib, and ado-trastuzumab emtansine (T-DM1) are commonly recommended anti-HER2 target agents by the U.S. Food and Drug Administration. This review summarizes the most significant and updated research on clinical scenarios related to HER2-positive breast cancer management in order to revise the guidelines of everyday clinical practices. In this article, we present the data on anti-HER2 clinical research of neoadjuvant, adjuvant, and metastatic studies from the past 2 decades. We also highlight some of the promising strategies that should be critically considered. Lastly, this review lists some of the ongoing clinical trials, findings of which may soon be available.

Post-Mastectomy Radiotherapy After Neoadjuvant Chemotherapy in Breast Cancer: A Pooled Retrospective Analysis of Three Prospective Randomized Trials

BACKGROUND

The impact of locoregional radiotherapy (RT) after neoadjuvant chemotherapy (NACT) and mastectomy in breast cancer patients is currently unclear. Several publications have suggested that patients with a favorable response to NACT might not benefit from RT after mastectomy.

METHODS

A retrospective analysis of three prospective randomized NACT trials was performed. Information on the use of RT was available for 817 breast cancer patients with non-inflammatory breast cancer who underwent mastectomy after NACT within the GeparTrio, GeparQuattro, and GeparQuinto-trials. RT was administered to 676 of these patients (82.7%).

RESULTS

The 5-year cumulative incidence of locoregional recurrence (LRR) was 15.2% (95% confidence interval [CI] 9.0-22.8%) in patients treated without RT and 11.3% in patients treated with RT (95% CI 8.7-14.3%). In the multivariate analysis, RT was associated with a lower risk of LRR (hazard ratio 0.51, 95% CI 0.27-1.0; p = 0.05). This effect was shown especially in patients with cT3/4 tumors, as well as in patients who were cN+ before neoadjuvant therapy, including those who converted to ypN0 after neoadjuvant therapy. In the bivariate analysis, disease-free survival was significantly worse in patients who received RT, however this was not confirmed in the multivariate analysis.

CONCLUSIONS

Our results suggest that RT reduces the LRR rates in breast cancer patients who receive a mastectomy after NACT without an improvement in DFS. Prospective randomized controlled trials such as the National Surgical Adjuvant Breast and Bowel Project B-51/RTOG 1304 trial will analyze whether RT has any benefit in patients who have a favorable response after NACT.

Fatal events during clinical trials: an evaluation of deaths during breast cancer studies

BACKGROUND

Information on deaths occurring during oncological clinical trials has never been systematically assessed. Here, we examine the incidence of death and the profile of patients who died during randomized clinical breast cancer (BC) trials.

METHODS

Information on fatal events during German Breast Group (GBG) led BC trials was prospectively captured. Data were derived from the trial databases and death narratives. All deaths were evaluated for possible causes, underlying conditions, treatment relatedness, time point and rate of autopsies.

RESULTS

From 12/1996 to 01/2017, 23,387 patients were treated within 32 trials. Of those 88 (0.4%) died on therapy within 17 trials. Median age was 64 [range 35-84] years, 63.2% of patients had a body mass index (BMI) ≥ 25 kg/m²; 65.9% 1-3 and 22.7% ≥ 4 comorbidities; 61.4% 1-2 cardiovascular risk factors (CRFs); 26.4% took > 3 drugs; 81.7% had ECOG 0; 50.0% stage III, 76.7% luminal BC. The main causes of death were infection (38.6%; of those, 82.3% sepsis, 17.6% pneumonia), heart failure (14.8%), and pulmonary embolism (13.6%). Fatal events mainly occurred within the first 4 therapy cycles (55.7%), in the investigational arm (66.7%) and under anthracycline-taxane-based chemotherapy (51.1%). A relationship with the treatment was declared in 27.3% of the cases. An autopsy was performed in 13.6% of patients.

CONCLUSIONS

Death during study treatment was mainly related to infections, and patients with advanced disease, high BMI, underlying comorbidities, CRFs and concomitant medications. If considered for study participation these patients need careful monitoring due to their higher risk for death on study.

Addition of Capecitabine in Breast Cancer First-line Chemotherapy Improves Survival of Breast Cancer Patients

Objective: Capecitabine is an antimetabolic fluoropyrimidine deoxynucleoside carbamate drug that can be converted to 5-FU in vivo. Currently, the role of capecitabine in the treatment of advanced breast cancer has been recognized. Also, Several meta-analyses have elucidated the role of capecitabine in the treatment of breast cancer, indicating that taxane-based regimen with capecitabine may be an effective, convenient, and well tolerated regimen in patients with early breast cancer. However, the correlation between capecitabine-based combination first-line chemotherapy and breast cancer survival remains unclear. Here, we present a meta-analysis to systematically evaluate the safety and effectiveness of capecitabine-based combination with first-line chemotherapy treatment in breast cancer. Methods: We searched Pubmed, Embase, and Medline for relevant studies evaluating pooled estimated hazard ratios of capecitabine in breast cancer patients with the eligible criteria up to June 2018. Fixed and random-effect meta-analyses were conducted based on heterogeneity of included studies. Results: Overall, 10 articles with 12,872 patients were included in the meta-analysis. Capecitabine-based combination first-line chemotherapy compared with non-combination had significant impacts on disease-free survival (HR = 0.84, 95% CI: 0.76-0.93; P = 0.000) and overall survival (HR = 0.84, 95% CI: 0.74-0.94; P = 0.001). Also, according to the 3 articles concerning neoadjuvant chemotherapy which included 2534 participants, we found that the addition of capecitabine significantly improved OS (HR = 0.89, 95% CI: 0.63-0.86; P = 0.011). In the subgroup analysis, TNBC patients got significant benefits with the addition of capecitabine in DFS (HR = 0.77, 95% CI: 0.65-0.92; P = 0.004) and OS (HR = 0.65, 95% CI: 0.51-0.81; P = 0.000). ER negative patients got significant benefits in OS (HR = 0.73, 95% CI: 0.57-0.93; P = 0.012). The association of DFS with the addition of capecitabine in Her- patients (HR = 0.84, 95% CI: 0.71-0.99; P = 0.005) was significant, as was OS (HR = 0.82, 95% CI: 0.70-0.95; P = 0.009),. Meanwhile, patients receiving capecitabine-based combination first-line chemotherapy underwent less adverse effects especially the grade 3/4 leucopenia than patients with non-combination therapy (RR=0.72 95% CI: 0.59-0.86; P = 0.000). Conclusion: Capecitabine combined with first-line chemotherapy in the treatment of breast cancer is an effective and safe treatment option and is worthy of clinical application to improve survival of breast cancer patients. In the future, we can continue to carry out relevant researches to explore the upmost appropriate dose of capecitabine for breast cancer.

A clinical perspective on escalating or de-escalating adjuvant therapy in HER2+ breast cancer

Introduction: Patients with early HER2-positive breast cancer (BC) benefit from HER2-targeted systemic therapy. The endorsed standard adjuvant treatment for patients with early HER2-positive breast cancer is chemotherapy plus trastuzumab administered for 1 year. Areas covered: Several trials have investigated modifications of the standard treatment in terms of de-escalation by either shortening the duration or giving less resource-demanding regimens and in terms of escalation by either adding a second anti-HER2 agent or extending the duration of HER2-targeted treatment for more than 12 months. In this perspective, we would offer a comprehensive view of these trials and discuss their findings. Expert commentary: At the current state of knowledge, there are still open questions regarding the management of HER2+ BC patients, such as the most adequate duration of trastuzumab therapy, the optimal chemotherapy regimen that should be combined with trastuzumab, and the addition of a second anti-HER2 agent. Growing evidences suggest that some HER2+ BC patients may not need chemotherapy. If these patients could be recognized upfront, optimal response could potentially be reached with HER2-targeted therapy alone.

The effect of participation in neoadjuvant clinical trials on outcomes in patients with early breast cancer

BACKGROUND

Clinical trials can offer novel and more advanced and/or novel treatments to cancer patients in advance of them being approved and available for all patients. While several studies have examined the effect of clinical trial participation on prognosis, there has been no clear conclusion from these studies. Therefore, we chose to test the influence of trial participation on pathological complete response (pCR) and mastectomy rates after neoadjuvant chemotherapy.

METHODS

In this retrospective study, all patients treated with neoadjuvant chemotherapy from 2001 to 2014 were selected. A total of 1038 patients with complete treatment, patient, and tumor characteristics were included. A total of 260 of those were treated in clinical trials. We examined whether study participation status in addition to commonly known predictors for pCR improves prediction of pCR. Similar analyses were conducted for the mastectomy rate outcome measure. Finally, survival analyses were also conducted as part of an exploratory analysis.

RESULTS

Study participation was an independent predictor of pCR in addition to commonly known predictors. Adjusted odds ratio (OR) for trial participants versus non-participants was 1.53 (95% CI 1.03-2.28). Additionally, study participation improved the prediction of mastectomy risk. The adjusted OR for trial participants versus non-participants was 0.62 (95% CI 0.42-0.90). Subgroup-specific differences concerning the impact of study participation could not be shown for either pCR or mastectomy rate. Survival comparisons could not be conducted due to large differences in follow-up data in patients participating in clinical trials versus those who did not participate; however, pCR was a predictor of prognosis in both groups.

CONCLUSION

Patients taking part in neoadjuvant chemotherapy clinical trials have a higher pCR rate and a lower mastectomy risk than patients not participating in clinical trials for their cancer care. This finding is a supporting factor for trial participation in neoadjuvant chemotherapy trials.

Five-year results of a phase II trial of preoperative 5-fluorouracil, epirubicin, cyclophosphamide followed by docetaxel with capecitabine (wTX) (with trastuzumab in HER2-positive patients) for patients with stage II or III breast cancer

We aimed to increase pathologic complete response (pCR) in patients with invasive breast cancer by adding preoperative capecitabine to docetaxel following 5-fluorouracil, epirubicin, cyclophosphamide (FEC) (with trastuzumab for patients with HER2-positive disease) and to evaluate 5-year disease-free survival (DFS) associated with this preoperative regimen. Chemotherapy included four cycles of FEC100 (5-fluorouracil 500 mg/m2 , epirubicin 100 mg/m2 , cyclophosphamide 500 mg/m2 IV on Day 1 every 21 days) followed by 4 21-day cycles of docetaxel (35 mg/m2  days 1 and 8) concurrently with capecitabine (825 mg/m2 orally twice daily for 14 days followed by 7 days off) (wTX). For HER2-positive patients, treatment was modified by decreasing epirubicin to 75 mg/m2 and adding trastuzumab (H) in standard doses (FEC75-H →wTX-H). The study objective was to achieve a pCR rate in the breast and axillary lymph nodes of 37% in patients with HER2-negative breast cancer and of 67% in patients with HER2-positive breast cancer treated with preoperative trastuzumab. A total of 186 patients were enrolled on study. In an intent-to-treat analysis, the pCR rate was 31% (37/118, 95% CI: 24-40%) in the HER2-negative patients, 24% (15/62, 95% CI: 14-37%) in ER-positive/HER2-negative patients, 39% (22/56, 95% CI: 27-53%) in the ER-negative/HER2-negative patients, and 46% (29/63, 95% CI: 34-48%) in the HER2-positive patients. The pCR rate in the 40 trastuzumab-treated patients was 53% (21/40, 95% CI: 38-67%). Grade 3 and 4 adverse events included neutropenia, leukopenia, diarrhea, and hand-foot skin reactions. One trastuzumab-treated patient developed grade 3 cardiotoxicity, and 4 others experienced grade 1-2 decrements in left ventricular function; all five patients' cardiac function returned to their baseline upon completion of trastuzumab. At 5 years, disease-free survival was 70% in the HER2-negative population (78% in ER-positive/HER2-negative and 62% in the ER-negative/HER2-negative patients) and 80% in the HER2-positive patients (87% in the trastuzumab-treated HER2-positive patients). At 5 years, overall survival was 80% in the HER2-negative population (88% in ER-positive/HER2-negative and 71% in the ER-negative/HER2-negative patients) and 86% in the HER2-positive patients (94.5% in the trastuzumab-treated HER2-positive patients). FEC100 (FEC75 with trastuzumab) followed by weekly docetaxel plus capecitabine, with or without trastuzumab is a safe, effective preoperative cytotoxic regimen. However, the addition of capecitabine to docetaxel following FEC, with or without trastuzumab, did not increase pCR rates nor 5-year DFS over the rates that have been reported with standard preoperative doxorubicin/cyclophosphamide (AC) followed by paclitaxel, with or without trastuzumab. Therefore, the use of capecitabine as part of preoperative chemotherapy is not recommended.

German Adjuvant Intergroup Node-positive Study (GAIN): a phase III trial comparing two dose-dense regimens (iddEPC versus ddEC-PwX) in high-risk early breast cancer patients

Background

Dose-dense (dd) regimens are one of the preferred options for the adjuvant treatment of breast cancer patients with intermediate to high risk. The German Adjuvant Intergroup Node-positive trial aimed at optimizing intense dd (idd) strategies by evaluating drug combinations and the addition of capecitabine.

Patients and methods

Women (aged 18 years and biologically <65 years) with histologically involved axillary lymph nodes were randomly assigned to receive three courses each of epirubicin (E) 150 mg/m2, paclitaxel (P) 225 mg/m2 and cyclophosphamide (C) 2500 mg/m2 (reduced to 2000 mg/m2 after recruitment of 1200 patients) q2w intravenously (i.v.) (iddEPC-regimen) or ddEC (E 112.5 mg/m2 + C 600 mg/m2, i.v. q2w for 4 cycles) followed by paclitaxel weekly (Pw 67.5 mg/m2 i.v. q8d for 10 weeks) plus capecitabine (X 2000 mg/m2 p.o. days 1-14, q22 for 4 cycles) (ddEC-PwX-regimen). Further randomization assigned patients to ibandronate for 2 years versus observation and to pegfilgrastim day 2 versus 4.

Results

From June 2004 to August 2008, 2994 patients were randomized to either iddEPC (N = 1498), or ddEC-PwX (N = 1496) and started treatment. Median age was 50 years; pN1 (37.8%), pN2 (35.3%); pN3 (26.9%); 46.4% were G3 tumors; 76.9% hormone receptor-positive and 22% HER2-positive. After a median follow-up of 74 months, 645 events and 383 deaths were recorded. Hematological adverse events grades 3-4 were more common with iddEPC (P < 0.001), nonhematological with ddEC-PwX (P = 0.04), even if the toxicity profile of the two regimens was different. At 5 years, estimated disease-free survival rates for ddEC-PwX and iddEPC were 81.7% [95% confidence interval (CI) 79.5-83.6] versus 80.2% (95% CI 78.0-82.2). Hazard ratio (HR)=0.95 (95% CI 0.81-1.11, log-rank P = 0.49). Five-year overall survival rates were 89.4% for ddEC-PwX (95% CI 87.7-91.0) and 89.0% for iddEPC (95% CI 87.2-90.6), HR = 0.85 (95% CI 0.69-1.04, log-rank P = 0.10).

Conclusion

Adding capecitabine to ddEC-Pw did not improve outcome in comparison to iddEPC but increased toxicity and should not be recommended for further use.

Optimal Management of Early and Advanced HER2 Breast Cancer

Approximately 15%-20% of breast cancer is HER2 positive, and patients with this subtype of disease historically had worse outcomes than patients with HER2-negative disease. However, the introduction of HER2-directed therapies has dramatically altered outcomes for these patients, especially for persons with early disease. However, despite these achievements, metastatic disease is still not curable. This review summarizes the current treatment approach for patients in the preoperative and adjuvant setting, including data regarding selecting the optimal chemotherapy partner as well as determining the duration and type of anti-HER-directed therapy. This article also reviews how to approach patients with advanced HER2-positive disease and discusses promising new therapies that are in development.

Evaluating the benefits and adverse effects of an enthracycline-taxane-capecitabine combined regimen in patients with early breast cancer

Capecitabine in addition to anthracycline-taxane based regimens for patients with early breast cancer (EBC) has been reported in previous clinical trials, but the reported efficacy of this regimen remained inconsistent. In order to clarify the survival benefit of this regimen, a meta-analysis was performed. The systematic literature search was conducted in PubMed, the Cochrane library and Google scholar. The hazard ratios (HRs) were used to evaluate the efficacy and adverse events. The result indicated that capecitabine combine with an anthracycline-taxane based regimen would significantly improve DFS (HR = 0.87, 95% CI 0.77-0.97) and OS (HR = 0.78, 95% CI 0.66-0.91) compared with the controls. In subgroup analysis, we found that capecitabine improved the DFS in hormone receptor negative (HR = 0.72, 95% CI 0.53-0.92) and triple negative (HR = 0.67, 95% CI 0.49-0.86) EBC patients. However, adding capecitabine might also increase the occurrence of some side-effects, such as hand-foot syndrome, stomatitis and diarrhea. Capecitabine combined with an anthracycline-taxane based regimen maybe effective and well-tolerated by patients with EBC, especially for triple negative breast cancer, and might be a good clinical choice.

Prognostic Impact of Circulating Tumor Cells for Breast Cancer Patients Treated in the Neoadjuvant "Geparquattro" Trial

Purpose: This study aimed to evaluate the prognostic impact of circulating tumor cells (CTC) detected in patients with operable or locally advanced breast cancer before and after neoadjuvant therapy (NT) within the clinical trial GeparQuattro.Experimental Design: Data on CTCs enumerated with the CellSearch system were available for 213 and 207 patients before and after NT, respectively. Associations of CTCs with disease-free survival (DFS) and overall survival (OS) were analyzed by nonparametric Kaplan-Meier estimates and parametric Cox regression.Results: After a median follow-up of 67.1 months, the detection of ≥1 CTC/7.5 mL and ≥2 CTCs/7.5 mL before NT was associated with reduced DFS (P = 0.031 and P < 0.0001, respectively) and OS (P = 0.0057 and P < 0.0001, respectively), whereas CTCs detected after NT did not correlate with DFS or OS. In parametric univariate and multivariate Cox models, ≥1 CTC/7.5 mL, ≥2 CTCs/7.5 mL, and absolute CTC numbers before NT revealed to be independent prognostic parameters of DFS and OS. CTC-negative patients with pathologic complete response (pCR) exhibited the best prognosis, whereas those with CTCs and less tumor response were at high risk of tumor relapse. In HER2 (ERBB2)-positive and triple-negative patients, ≥2 CTCs/7.5 mL detected before NT also were significantly associated with worse DFS and OS.Conclusions: Detection of CTCs before NT is an independent prognostic factor of impaired clinical outcome, and combined with pCR, it could be helpful to stratify breast cancer patients for therapeutic interventions. Clin Cancer Res; 23(18); 5384-93. ©2017 AACR.

ADAM12-L confers acquired 5-fluorouracil resistance in breast cancer cells

5-FU-based combinatory chemotherapeutic regimens have been routinely used for many years for the treatment of breast cancer patients. Recurrence and chemotherapeutic drug resistance are two of the most prominent factors that underpin the high mortality rates associated with most breast cancers (BC). Increasing evidence indicates that overexpression of ADAMs could correlate with cancer progression. However, the role of ADAMs in the chemoresistance of cancer cells has rarely been reported. In this study, we observed that 5-FU induces expression of the ADAM12 isoform ADAM12-L but not ADAM12-S in BC cells and in recurrent BC tissues. The overexpression of ADAM12-L in BC cells following 5-FU treatment results in the acquisition of resistance to 5-FU. ADAM12-L overexoression also resulted in increased levels of p-Akt but not p-ERK. These alterations enhanced BC cell growth and invasive abilities. Conversely, ADAM12 knockdown attenuated the levels of p-Akt and restored 5-FU sensitivity in 5-FU-resistant BC cells. ADAM12 knockdown also reduced BC cell survival and invasive abilities. These findings suggest that ADAM12-L mediates chemoresistance to 5-FU and 5-FU-induced recurrence of BC by enhancing PI3K/Akt signaling. The results of this study suggest that specific ADAM12-L inhibition could optimize 5-FU-based chemotherapy of BC, thereby preventing BC recurrence in patients.

Adjuvant Capecitabine in Combination With Docetaxel, Epirubicin, and Cyclophosphamide for Early Breast Cancer: The Randomized Clinical FinXX Trial

Importance

Capecitabine is not considered a standard agent in the adjuvant treatment of early breast cancer. The results of this study suggest that addition of adjuvant capecitabine to a regimen that contains docetaxel, epirubicin, and cyclophosphamide improves survival outcomes of patients with triple-negative breast cancer (TNBC).

Objective

To investigate the effect of capecitabine on long-term survival outcomes of patients with early breast cancer, particularly in subgroups defined by cancer estrogen receptor (ER) and progesterone receptor (PR) content, and HER2 content (human epidermal growth factor receptor 2).

Design, Setting, and Participants

This is an exploratory analysis of the multicenter FinXX randomized clinical trial that accrued 1500 women in Finland and Sweden between January 27, 2004, and May 29, 2007. About half received 3 cycles of docetaxel followed by 3 cycles of cyclophosphamide, epirubicin, and fluorouracil (T+CEF), while the other half received 3 cycles of docetaxel plus capecitabine followed by 3 cycles of cyclophosphamide, epirubicin, and capecitabine (TX+CEX). Data analysis took place between January 27, 2004, and December 31, 2015.

Main Outcomes and Measures

Recurrence-free survival (RFS).

Results

Following random allocation, 747 women received T+CEF, and 753 women received TX+CEX. Five patients were excluded from the intention-to-treat population (3 had overt distant metastases at the time of randomization; 2 withdrew consent). The median age of the remaining 1495 patients was 53 years at the time of study entry; 157 (11%) had axillary node-negative disease; 1142 (76%) had ER-positive cancer; and 282 (19%) had HER2-positive cancer. The median follow-up time after random allocation was 10.3 years. There was no significant difference in RFS or overall survival between the groups (hazard ratio [HR], 0.88; 95% CI, 0.71-1.08; P = .23; and HR, 0.84, 95% CI, 0.66-1.07; P = .15; respectively). Breast cancer-specific survival tended to favor the capecitabine group (HR, 0.79; 95% CI, 0.60-1.04; P = .10). When RFS and survival of the patients were compared within the subgroups defined by cancer steroid hormone receptor status (ER and/or PR positive vs ER and PR negative) and HER2 status (positive vs negative), TX+CEX was more effective than T+CEF in the subset of patients with TNBC (HR, 0.53; 95% CI, 0.31-0.92; P = .02; and HR, 0.55, 95% CI, 0.31-0.96; P = .03; respectively).

Conclusions and Relevance

Capecitabine administration with docetaxel, epirubicin, and cyclophosphamide did not prolong RFS or survival compared with a regimen that contained only standard agents. Patients with TNBC had favorable survival outcomes when treated with the capecitabine-containing regimen in an exploratory subgroup analysis.

Trial Registration

clinicaltrials.gov Identifier: NCT00114816.

Adding Adjuvant Systemic Treatment after Neoadjuvant Therapy in Breast Cancer: Review of the Data

PURPOSE OF REVIEW

Residual disease after neoadjuvant chemotherapy is a poor prognostic factor; however, proven strategies to reduce recurrence risk and improve overall survival in this patient population are limited. Previous studies of residual disease have illustrated the importance of tumor intrinsic subtypes in treatment response and mechanisms of resistance. This review summarizes the rationale for various therapeutic approaches as well as completed and ongoing clinical trials for this high-risk group of patients.

RECENT FINDINGS

Regimens utilizing additional chemotherapy and targeted therapies (such as PARP inhibitors or bisphosphonates) have met with limited efficacy. Notably, a recently published randomized study of capecitabine in patients with residual disease demonstrated an improvement in disease-free survival and overall survival. While the results for capecitabine are promising, particularly for patients with triple-negative disease, the generalizability of these findings is an open question. Meanwhile, ongoing trials with novel agents that target specific tumor subtypes and the biology of residual disease may improve outcomes for other patient populations.

Capecitabine in early breast cancer: A meta-analysis of randomised controlled trials

PURPOSE

Capecitabine is an effective therapy for metastatic breast cancer. Its role in early breast cancer is uncertain due to conflicting data from randomised controlled trials (RCTs).

METHODS

PubMed and major conference proceedings were searched to identify RCTs comparing standard chemotherapy with or without capecitabine in the neoadjuvant or adjuvant setting. Hazard ratios (HRs) for disease-free survival (DFS) and overall survival (OS), as well as odds ratios (ORs) for toxicities were extracted or calculated and pooled in a meta-analysis. Subgroup analysis compared triple-negative breast cancer (TNBC) to non-TNBC and whether capecitabine was given in addition to or in place of standard chemotherapy. Meta-regression was used to explore the influence of TNBC on OS.

RESULTS

Eight studies comprising 9302 patients were included. In unselected patients, capecitabine did not influence DFS (hazard ratio [HR] 0.99, p = 0.93) or OS (HR 0.90, p = 0.36). There was a significant difference in DFS when capecitabine was given in addition to standard treatment compared with in place of standard treatment (HR 0.92 versus 1.62, interaction p = 0.002). Addition of capecitabine to standard chemotherapy was associated with significantly improved DFS in TNBC versus non-TNBC (HR 0.72 versus 1.01, interaction p = 0.02). Meta-regression showed that adding capecitabine to standard chemotherapy was associated with improved OS in studies with higher proportions of patients with TNBC (R = -0.967, p = 0.007). Capecitabine increased grade 3/4 diarrhoea (odds ratio [OR] 2.33, p < 0.001) and hand-foot syndrome (OR 8.08, p < 0.001), and resulted in more frequent treatment discontinuation (OR 3.80, p < 0.001).

CONCLUSION

Adding capecitabine to standard chemotherapy appears to improve DFS and OS in TNBC, but increases adverse events in keeping with its known toxicity profile.

Clinical Value of Capecitabine-Based Combination Adjuvant Chemotherapy in Early Breast Cancer: A Meta-Analysis of Randomized Controlled Trials

Capecitabine has consistently demonstrated high efficacy and acceptable tolerability in salvage chemotherapy for advanced breast cancer. However, there remains no consensus on its role in adjuvant chemotherapy for early breast cancer (EBC). To estimate the value of capecitabine-based combination adjuvant treatment in EBC, eight randomized controlled trials with 14,072 participants were analyzed. The efficacy and safety outcomes included disease-free survival (DFS), overall survival (OS), relapse, breast cancer-specific survival (BCSS), and grades 3-5 adverse events. Capecitabine-based combination adjuvant chemotherapy demonstrated a 16% increase in BCSS (HR = 0.84, 95% CI = 0.71-0.98, p = 0.03) in the overall analysis and a 22% improvement in DFS (HR = 0.78, 95% CI = 0.64-0.96, p = 0.02) in the hormone receptor-negative (HR-) subgroup. However, there were no significant differences in DFS (HR = 0.96, 95% CI = 0.89-1.05, p = 0.38), OS (HR = 0.91, 95% CI = 0.82-1.00, p = 0.06), or relapse between capecitabine-based and capecitabine-free combination adjuvant chemotherapy. Analogous results were observed in the subgroup analyses of HR+, HER2-, HER2+, and triple-negative EBC. Regarding safety, reduced myelosuppression and hand-foot syndrome development were observed in capecitabine-treated patients. Capecitabine-based combination adjuvant chemotherapy might provide some BCSS benefit compared with capecitabine-free regimens in EBC, but the absolute survival gain is small, and the survival benefit appears to be restricted to patients with HR- EBC, which may indicate a target population for capecitabine-based combination adjuvant chemotherapy.

Bevacizumab Addition in Neoadjuvant Treatment Increases the Pathological Complete Response Rates in Patients with HER-2 Negative Breast Cancer Especially Triple Negative Breast Cancer: A Meta-Analysis

Background

Neoadjuvant therapy is administered to breast cancer patients as an induction process before surgery or radiotherapy to reduce tumor size. Human epidermal growth factor receptor-2 (HER-2) negative breast cancer lacks effective standard target therapy. Bevacizumab has a controversial role in the treatment of breast cancer and we conduct a meta-analysis to evaluate the value of adding bevacizumab in neoadjuvant regimen.

Methods

Potentially eligible studies were retrieved using PubMed, EMBASE and Medline. Clinical characteristics of patients and statistical data with pathological complete response (pCR) data were collected. Then a meta-analysis model was established to investigate the correlation between administration of bevacizumab in neoadjuvant therapy and pCR rates in HER-2 negative breast cancer.

Results

Seven eligible studies and 5408 patients were yielded. The pCR rates for “breast” or “breast plus lymph node” were similar. In subgroup analysis, we emphasized on patients with triple-negative breast cancer (TNBC). In the criterion of “lesions in breast” the pooled ORs was 1.55 [1.29, 1.86], P<0.00001 and regarding to the evaluation criterion of “lesions in breast and lymph nodes”, the pooled ORs was 1.48 [1.23, 1.78], P<0.0001, in favor of bevacizumab administration.

Conclusion

According to our pooled results, we finally find that bevacizumab addition as a neoadjuvant chemotherapy component, for induction use with limited cycle to improve the pCR rates and patients may avoid long-term adverse event and long-term invalid survival improvement. Especially in subgroup analysis, pCR rates could be improved significantly and physicians could consider bevacizumab with caution. As patients could avoid the adverse event caused by long-term using of bevacizumab, long-term quality of life improvement may be achieved, especially in TNBC.

5-year analysis of neoadjuvant pertuzumab and trastuzumab in patients with locally advanced, inflammatory, or early-stage HER2-positive breast cancer (NeoSphere): a multicentre, open-label, phase 2 randomised trial

BACKGROUND

In the primary analysis of the NeoSphere trial, patients given neoadjuvant pertuzumab, trastuzumab, and docetaxel showed a significantly improved pathological complete response compared with those given trastuzumab and docetaxel after surgery. Here, we report 5-year progression-free survival, disease-free survival, and safety.

METHODS

In this multicentre, open-label, phase 2 randomised trial in hospitals and medical clinics, treatment-naive adults with locally advanced, inflammatory, or early-stage HER2-positive breast cancer were randomly assigned (1:1:1:1) to receive four neoadjuvant cycles of trastuzumab (8 mg/kg loading dose, followed by 6 mg/kg every 3 weeks) plus docetaxel (75 mg/m(2) every 3 weeks, increasing to 100 mg/m(2) from cycle 2 if tolerated; group A), pertuzumab (840 mg loading dose, followed by 420 mg every 3 weeks) and trastuzumab plus docetaxel (group B), pertuzumab and trastuzumab (group C), or pertuzumab and docetaxel (group D). After surgery, patients received three cycles of FEC (fluorouracil 600 mg/m(2), epirubicin 90 mg/m(2), and cyclophosphamide 600 mg/m(2)) every 3 weeks (patients in group C received four cycles of docetaxel prior to FEC), and trastuzumab 6 mg/kg every 3 weeks to complete 1 year's treatment (17 cycles in total). Randomisation was done by a central centre using dynamic allocation, stratified by operable, locally advanced, and inflammatory breast cancer, and by oestrogen and/or progesterone receptor positivity. Safety analyses were done according to treatment received. The primary endpoint (pathological complete response) was previously reported; secondary endpoints reported here are 5-year progression-free survival (analysed in the intention-to-treat population) and disease-free survival (analysed in patients who had surgery). Secondary and exploratory analyses were not powered for formal statistical hypothesis testing, and therefore results are for descriptive purposes only. The study ended on Sept 22, 2014 (last patient, last visit). This study is registered with ClinicalTrials.gov, number NCT00545688.

FINDINGS

Between Dec 17, 2007, and Dec 22, 2009, 417 eligible patients were randomly assigned to group A (107 patients), group B (107 patients), group C (107 patients), or group D (96 patients). One patient in group A withdrew before treatment. One patient assigned to group D received group A treatment, one patient assigned to group D received group B treatment, and one patient assigned to group B received group C treatment. At clinical cutoff, 87 patients had progressed or died. 5-year progression-free survival rates were 81% (95% CI 71-87) for group A, 86% (77-91) for group B, 73% (64-81) for group C, and 73% (63-81) for group D (hazard ratios 0·69 [95% CI 0·34-1·40] group B vs group A, 1·25 [0·68-2·30] group C vs group A, and 2·05 [1·07-3·93] group D vs group B). Disease-free survival results were consistent with progression-free survival results and were 81% (95% CI 72-88) for group A, 84% (72-91) for group B, 80% (70-86) for group C, and 75% (64-83) for group D. Patients who achieved total pathological complete response (all groups combined) had longer progression-free survival compared with patients who did not (85% [76-91] in patients who achieved total pathological response vs 76% [71-81] in patients who did not achieve total pathological response; hazard ratio 0·54 [95% CI 0·29-1·00]). There were no new or long-term safety concerns and tolerability was similar across groups (neoadjuvant and adjuvant treatment periods combined). The most common grade 3 or worse adverse events were neutropenia (group A: 71 [66%] of 107 patients; group B: 59 [55%] of 107; group C: 40 [37%] of 108; group D: 60 [64%] of 94), febrile neutropenia (group A: 10 [9%]; group B: 12 [11%]; group C: 5 [5%]; group D: 15 [16%]), and leucopenia (group A: 13 [12%]; group B: 6 [6%]; group C: 4 [4%]; group D: 8 [9%]). The number of patients with one or more serious adverse event was similar across groups (19-22 serious adverse events per group in 18-22% of patients).

INTERPRETATION

Progression-free survival and disease-free survival at 5-year follow-up show large and overlapping CIs, but support the primary endpoint (pathological complete response) and suggest that neoadjuvant pertuzumab is beneficial when combined with trastuzumab and docetaxel. Additionally, they suggest that total pathological complete response could be an early indicator of long-term outcome in early-stage HER2-positive breast cancer.

FUNDING

F Hoffmann-La Roche.

Capecitabine in Combination with Standard (Neo)Adjuvant Regimens in Early Breast Cancer: Survival Outcome from a Meta-Analysis of Randomized Controlled Trials

Capecitabine has been investigated in early breast cancer in several studies, but it was undefined that whether it could improve survival. To investigate whether the addition of capecitabine affected survival in patients with early breast cancer, a meta-analysis was conducted and overall survival (OS), disease-free survival (DFS), and toxicity were assessed. The PubMed, Embase databases and the Cochrane Central Register of Controlled Trials were searched for studies between January 2006 and April 2016. Hazard ratios (HRs) with their 95% confidence intervals (CIs), or data for calculating HRs with 95% CI were derived. Seven trials with 9097 patients, consisted of 4 adjuvant and 3 neoadjuvant studies, were included in this meta-analysis. Adding capecitabine showed no improvement in DFS (HR = 0.93; 95% CI, 0.85-1.02; P = 0.12), whereas a significant improvement in OS was observed (HR = 0.85; 95% CI, 0.75-0.96; P = 0.008). A sub-analysis of DFS showed that benefit of capecitabine derived from patients with triple negative subtype and with extensive axillary involvement. Safety profiles were consistent with the known side-effects of capecitabine, but more patients discontinued scheduled treatment in the capecitabine group. Combining capecitabine with standard (neo)adjuvant regimens in early breast cancer demonstrated a significantly superior OS, and indicated DFS improvement in some subtypes with high risk of recurrence. Selection of subtypes was a key to identify patients who might gain survival benefit from capecitabine.

Neoadjuvant treatment of breast cancer: maximizing pathologic complete response rates to improve prognosis

PURPOSE OF REVIEW

Neoadjuvant therapy is very often an adequate alternative to adjuvant therapy. This review summarizes the recent advances made in the area of neoadjuvant therapy in breast cancer. The focus will lie on recently published clinical trials, but will not further highlight surgical, imaging and radio-oncological issues related to neoadjuvant therapy.

RECENT FINDINGS

Within the past year, it has been discussed if neoadjuvant treatment can be used as a faster way to get access to new therapies, based on new data in HER2+ breast cancer, suggesting a higher pathological complete response rate when a dual anti-HER2 therapy was used. Nevertheless, this higher pathological complete response rate does not necessarily always translate into a better survival. In triple negative breast cancer, carboplatin could be identified as an asset for patients, especially in patients with gBRCA mutations. However, mature long-term data are still missing. The neoadjuvant approach is ideal to identify new biomarkers which predict response or resistance to the given treatment. Tumour-infiltrating lymphocytes and PIK3CA mutations are amongst the most promising markers.

SUMMARY

Neoadjuvant treatment should be considered for all patients with HER2-positive or triple negative breast cancer. Clinical trials in this setting are currently investigating new approaches.

Neoadjuvant breast cancer treatment as a sensitive setting for trastuzumab biosimilar development and extrapolation

ABSTRACT 

Aims: Identify sensitive end points and populations for similarity studies of trastuzumab and biosimilar monoclonal antibodies. Methods: We performed meta-analyses of trastuzumab clinical trials data: overall response rate (ORR) and progression-free survival in metastatic breast cancer (MBC), and total pathologic complete response (tpCR) and event-free survival in the neoadjuvant setting. Fitted models predicted the maximum loss in long-term efficacy for different similarity trial designs. Immunogenicity rates were investigated in different early breast cancer (EBC) study phases. Results: Using the same equivalence margins for ORR (MBC) and tpCR (EBC), the predicted maximum loss in long-term efficacy with a biosimilar candidate versus the reference product is smaller for tpCR than for ORR. In EBC this predicted loss could be controlled with feasible patient numbers for a typical clinical trial. Analyses suggested that a treatment-free follow-up phase is preferable for immunogenicity characterization. Conclusion: Treatment of patients with neoadjuvant breast cancer represents a sensitive setting for establishing biosimilarity of efficacy and immunogenicity. tpCR is a sensitive end point in this setting to establish biosimilarity between a biosimilar candidate and its reference product.

Pathologic complete response as a potential surrogate for the clinical outcome in patients with breast cancer after neoadjuvant therapy: a meta-regression of 29 randomized prospective studies

PURPOSE

To assess the role of pathologic complete response (pCR) after neoadjuvant therapy as surrogate end point of disease-free survival (DFS) and overall survival (OS) in patients with breast cancer, we performed a trial-based meta-regression of randomized studies comparing different neoadjuvant systemic treatments.

METHODS

The systematic literature search included electronic databases and proceedings of oncologic meetings. Endocrine therapy trials were excluded. Treatment effects on DFS and OS were expressed as hazard ratios (HRs), and treatment effects on pCR were expressed as odds ratios (ORs). A weighted regression analysis was performed on log-transformed treatment effect estimates to test the association between treatment effects on the surrogate outcome and treatment effects on the clinical outcome.

RESULTS

Twenty-nine trials, 59 arms, and 30 comparisons, for a total of 14,641 patients, were included in the analysis. Using the complete set of data, the regression of either the log(HR) for DFS or the log(HR) for OS on the log(OR) for pCR demonstrated only weak associations (R(2) = 0.08; 95% CI, 0 to 0.47; and R(2) = 0.09; 95% CI, 0.01 to 0.41, respectively). Better associations were found in an exploratory analysis assessing a subset of trials comparing intensified/dose-dense chemotherapy versus standard-dose regimens (DFS: R(2) = 0.79; 95% CI, 0.26 to 0.95; P = .003; and OS: R(2) = 0.57; 95% CI, 0.19 to 0.93; P = .03).

CONCLUSION

This meta-regression analysis of 29 heterogeneous neoadjuvant trials does not support the use of pCR as a surrogate end point for DFS and OS in patients with breast cancer. However, pCR may potentially meet the criteria of surrogacy with specific systemic therapies.

PIK3CA mutations are associated with lower rates of pathologic complete response to anti-human epidermal growth factor receptor 2 (her2) therapy in primary HER2-overexpressing breast cancer

PURPOSE

Phosphatidylinositol 3-kinase (PI3K)/AKT pathway aberrations are common in breast cancer, with mutations in PIK3CA being the most common. This study investigated the association between PIK3CA genotype and pathologic complete response (pCR) rates in human epidermal growth factor receptor 2 (HER2)-positive breast cancer treated with either dual or single anti-HER2 treatment in addition to neoadjuvant chemotherapy.

PATIENTS AND METHODS

PIK3CA mutations in 504 tumor samples from participants in the neoadjuvant GeparQuattro, GeparQuinto, and GeparSixto studies were evaluated. All HER2-positive patients received either trastuzumab or lapatinib or the combination plus anthracycline-taxane chemotherapy. PIK3CA mutations were evaluated in formalin-fixed, paraffin-embedded tissues from core biopsies with a tumor cell content of ≥ 20% by using classical Sanger sequencing of exon 9 and exon 20.

RESULTS

Overall, 21.4% of the patients harbored a PIK3CA mutation. Detection of a PIK3CA mutation was significantly associated with a lower pCR rate (19.4% with PIK3CA mutation v 32.8% with PIK3CA wild-type; odds ratio [OR], 0.49; 95% CI, 0.29 to 0.83; P = .008). In the 291 hormone receptor (HR) -positive tumors, pCR rate was 11.3% with a PIK3CA mutation compared with 27.5% with PIK3CA wild-type (OR, 0.34; 95% CI, 0.15 to 0.78; P = .011). In 213 patients with HR-negative tumors, pCR rate was 30.4% with PIK3CA mutation and 40.1% without (OR, 0.65; 95% CI, 0.32 to 1.32; P = .233; interaction test P = .292). In multivariable analysis, HR status and PIK3CA status provided independent predictive information. In patients with PIK3CA mutation, the pCR rates were 16%, 24.3%, and 17.4% with lapatinib, trastuzumab, and the combination, respectively (P = .654) and in the wild-type group, they were 18.2%, 33.%, and 37.1%, respectively (P = .017). Disease-free survival and overall survival were not statistically significantly different between patients with mutant and wild-type PIK3CA.

CONCLUSION

HER2-positive breast carcinomas with a PIK3CA mutation are less likely to achieve a pCR after neoadjuvant anthracycline-taxane-based chemotherapy plus anti-HER2 treatment, even if a dual anti-HER2 treatment is given.