On-treatment biopsies to predict response to neoadjuvant chemotherapy for breast cancer.

BACKGROUND: Patients with pathologic complete response (pCR) to neoadjuvant chemotherapy for invasive breast cancer (BC) have better outcomes, potentially warranting less extensive surgical and systemic treatments. Early prediction of treatment response could aid in adapting therapies. METHODS: On-treatment biopsies from 297 patients with invasive BC in three randomized, prospective neoadjuvant trials were assessed (GeparQuattro, GeparQuinto, GeparSixto). BC quantity, tumor-infiltrating lymphocytes (TILs), and the proliferation marker Ki-67 were compared to pre-treatment samples. The study investigated the correlation between residual cancer, changes in Ki-67 and TILs, and their impact on pathologic complete response (pCR) and disease-free survival (DFS). RESULTS: Among the 297 samples, 138 (46%) were hormone receptor-positive (HR+)/human epidermal growth factor 2-negative (HER2-), 87 (29%) were triple-negative (TNBC), and 72 (24%) were HER2+. Invasive tumor cells were found in 70% of on-treatment biopsies, with varying rates across subtypes (HR+/HER2-: 84%, TNBC: 62%, HER2+: 51%; p < 0.001). Patients with residual tumor on-treatment had an 8% pCR rate post-treatment (HR+/HER2-: 3%, TNBC: 19%, HER2+: 11%), while those without any invasive tumor had a 50% pCR rate (HR+/HER2-: 27%; TNBC: 48%, HER2+: 66%). Sensitivity for predicting residual disease was 0.81, with positive and negative predictive values of 0.92 and 0.50, respectively. Increasing TILs from baseline to on-treatment biopsy (if residual tumor was present) were linked to higher pCR likelihood in the overall cohort (OR 1.034, 95% CI 1.013-1.056 per % increase; p = 0.001) and with a longer DFS in TNBC (HR 0.980, 95% CI 0.963-0.997 per % increase; p = 0.026). Persisting or increased Ki-67 was associated with with lower pCR probability in the overall cohort (OR 0.957, 95% CI 0.928-0.986; p = 0.004) and shorter DFS in TNBC (HR 1.023, 95% CI 1.001-1.047; p = 0.04). CONCLUSION: On-treatment biopsies can predict patients unlikely to achieve pCR post-therapy. This could facilitate therapy adjustments for TNBC or HER2 + BC. They also might offer insights into therapy resistance mechanisms. Future research should explore whether standardized or expanded sampling enhances the accuracy of on-treatment biopsy procedures. Trial registration GeparQuattro (EudraCT 2005-001546-17), GeparQuinto (EudraCT 2006-005834-19) and GeparSixto (EudraCT 2011-000553-23).

Breast Cancer Index in Premenopausal Women With Early-Stage Hormone Receptor-Positive Breast Cancer.

Importance: Adjuvant ovarian function suppression (OFS) with oral endocrine therapy improves outcomes for premenopausal patients with hormone receptor-positive (HR+) breast cancer but adds adverse effects. A genomic biomarker for selecting patients most likely to benefit from OFS-based treatment is lacking. Objective: To assess the predictive and prognostic performance of the Breast Cancer Index (BCI) for OFS benefit in premenopausal women with HR+ breast cancer. Design, Setting, and Participants: This prospective-retrospective translational study used all available tumor tissue samples from female patients from the Suppression of Ovarian Function Trial (SOFT). These individuals were randomized to receive 5 years of adjuvant tamoxifen alone, tamoxifen plus OFS, or exemestane plus OFS. BCI testing was performed blinded to clinical data and outcome. The a priori hypothesis was that BCI HOXB13/IL17BR ratio (BCI[H/I])-high tumors would benefit more from OFS and high BCI portended poorer prognosis in this population. Settings spanned multiple centers internationally. Participants included premenopausal female patients with HR+ early breast cancer with specimens in the International Breast Cancer Study Group tumor repository available for RNA extraction. Data were collected from December 2003 to April 2021 and were analyzed from May 2022 to October 2022. Main Outcomes and Measures: Primary end points were breast cancer-free interval (BCFI) for the predictive analysis and distant recurrence-free interval (DRFI) for the prognostic analyses. Results: Tumor specimens were available for 1718 of the 3047 female patients in the SOFT intention-to-treat population. The 1687 patients (98.2%) who had specimens that yielded sufficient RNA for BCI testing represented the parent trial population. The median (IQR) follow-up time was 12 (10.5-13.4) years, and 512 patients (30.3%) were younger than 40 years. Tumors were BCI(H/I)-low for 972 patients (57.6%) and BCI(H/I)-high for 715 patients (42.4%). Patients with tumors classified as BCI(H/I)-low exhibited a 12-year absolute benefit in BCFI of 11.6% from exemestane plus OFS (hazard ratio [HR], 0.48 [95% CI, 0.33-0.71]) and an absolute benefit of 7.3% from tamoxifen plus OFS (HR, 0.69 [95% CI, 0.48-0.97]) relative to tamoxifen alone. In contrast, patients with BCI(H/I)-high tumors did not benefit from either exemestane plus OFS (absolute benefit, -0.4%; HR, 1.03 [95% CI, 0.70-1.53]; P for interaction = .006) or tamoxifen plus OFS (absolute benefit, -1.2%; HR, 1.05 [95% CI, 0.72-1.54]; P for interaction = .11) compared with tamoxifen alone. BCI continuous index was significantly prognostic in the N0 subgroup for DRFI (n = 1110; P = .004), with 12-year DRFI of 95.9%, 90.8%, and 86.3% in BCI low-risk, intermediate-risk, and high-risk N0 cancers, respectively. Conclusions and Relevance: In this prospective-retrospective translational study of patients enrolled in SOFT, BCI was confirmed as prognostic in premenopausal women with HR+ breast cancer. The benefit from OFS-containing adjuvant endocrine therapy was greater for patients with BCI(H/I)-low tumors than BCI(H/I)-high tumors. BCI(H/I)-low status may identify premenopausal patients who are likely to benefit from this more intensive endocrine therapy.

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.

Laparoscopic surgery for endometrial cancer is oncologically safe and improves hospital stay duration: a retrospective single-center study over a 16-year period.

OBJECTIVE: To investigate changes in surgical procedures and patient outcomes of patients diagnosed with endometrial cancer (EC) at a German university hospital between 1998 and 2014. METHODS: A monocentric, retrospective review was conducted to identify patients diagnosed and treated with EC during the aforementioned period at the Department of Gynecology and Obstetrics at the University Hospital Kiel, Germany. RESULTS: 303 patients were identified. Patient demographics, risk factors, histological subtypes and stages of EC remained consistent over time. The most common surgical procedure was total abdominal hysterectomy (TAH) (81.9%). In 2011, the institution carried out its first total laparoscopic hysterectomy (TLH) for EC, resulting in a significant increase in laparoscopic surgical procedures (2011-2014: N = 70; TAH 44.2%; TLH 51.4%). Although the total number of lymph node stagings remained consistent over time, there was a significant increase in the performance of simultaneous pelvic and para-aortic lymphonodectomy (LNE) compared to pelvic LNE alone (2.6 in 2001-2005 vs. 18.0% in 2011-2014, p ≤ 0.001). The duration of hospital stays significantly decreased over time, with a mean of 20.9 days in the first and 8.5 days in the last period. When comparing surgical procedures, TLHs resulted in significantly shorter postoperative stays with an average of 6.58 vs. 13.92 days for TAH. The surgical procedure performed did not affect 5-year overall survival rates in this study (84.9% for TAH and 85.3% for TLH, p = 0.85). CONCLUSIONS: Our retrospective single-center study demonstrates that laparoscopic surgery for endometrial cancer is oncologically safe and shortens hospital stays.

Decision Coaching for Healthy Women With BRCA1/2 Pathogenic Variants.

BACKGROUND: Women with pathogenic variants (PV) of the genes BRCA1/2 have a choice of preventive options. To help these women decide for themselves, we developed and implemented a decision coaching (DC) program and evaluated it for congruence between the participants' desired and actual roles in decision-making. METHODS: Healthy BRCA1/2 PV carriers (25-60 years of age) were recruited at six centers in Germany. Those who returned baseline (T1) questionnaires were randomly assigned to the intervention group (IG) or the control group (CG). The IG attended a nurse-led DC program. The primary outcome was congruence between the participants' preferred and actual roles in decision-making. The secondary outcomes were an active role, satisfaction, decisional conflict, and knowledge. The follow-up questionnaires were administered at 12 weeks (T2) and 6 months (T3). RESULTS: Of the 413 women who were recruited, 389 returned the T1 questionnaires. At T2, the groups did not differ significantly in congruence between their preferred and actual roles in decision-making (0.12, 95% confidence interval [-0.03; 0.28], p = 0.128), with a slightly higher congruence in the CG. Women in both groups played a more active role at T2 than their stated preference at T1, with a notably higher percentage in the IG than the CG (IG: 40%, CG: 24.4% [-25.1; -6.1]). IG participants were more satisfied with their role and had less decisional conflict and greater knowledge. CONCLUSION: This DC program can help women who are carriers of BRCA1/2 PV participate actively in decision-making with regard to preventive measures.

Radiotherapy statements of the 18th St. Gallen International Breast Cancer Consensus Conference-a German expert perspective.

PURPOSE: To summarize the radiotherapy-relevant statements of the 18th St. Gallen Breast Cancer Consensus Conference and interpret the findings in light of German guideline recommendations. METHODS: Statements and voting results from the 18th St. Gallen International Breast Cancer Consensus Conference were collected and analyzed according to their relevance for the radiation oncology community. The voting results were discussed in two hybrid meetings among the authors of this manuscript on March 18 and 19, 2023, in light of the German S3 guideline and the 2023 version of the Arbeitsgemeinschaft Gynäkologische Onkologie (AGO) guidelines. RESULTS AND CONCLUSION: There was a high level of agreement between the radiotherapy-related statements of the 18th St. Gallen International Breast Cancer Consensus Conference and the German S3 and AGO guidelines. Discrepancies include the impact of number of lymph node metastases for the indication for postmastectomy radiotherapy.

Minimally Invasive Breast Biopsy After Neoadjuvant Systemic Treatment to Identify Breast Cancer Patients with Residual Disease for Extended Neoadjuvant Treatment: A New Concept.

BACKGROUND: Breast cancer patients with residual disease after neoadjuvant systemic treatment (NAST) have a worse prognosis compared with those achieving a pathologic complete response (pCR). Earlier identification of these patients might allow timely, extended neoadjuvant treatment strategies. We explored the feasibility of a vacuum-assisted biopsy (VAB) after NAST to identify patients with residual disease (ypT+ or ypN+) prior to surgery. METHODS: We used data from a multicenter trial, collected at 21 study sites (NCT02948764). The trial included women with cT1-3, cN0/+ breast cancer undergoing routine post-neoadjuvant imaging (ultrasound, MRI, mammography) and VAB prior to surgery. We compared the findings of VAB and routine imaging with the histopathologic evaluation of the surgical specimen. RESULTS: Of 398 patients, 34 patients with missing ypN status and 127 patients with luminal tumors were excluded. Among the remaining 237 patients, tumor cells in the VAB indicated a surgical non-pCR in all patients (73/73, positive predictive value [PPV] 100%), whereas PPV of routine imaging after NAST was 56.0% (75/134). Sensitivity of the VAB was 72.3% (73/101), and 74.3% for sensitivity of imaging (75/101). CONCLUSION: Residual cancer found in a VAB specimen after NAST always corresponds to non-pCR. Residual cancer assumed on routine imaging after NAST corresponds to actual residual cancer in about half of patients. Response assessment by VAB is not safe for the exclusion of residual cancer. Response assessment by biopsies after NAST may allow studying the new concept of extended neoadjuvant treatment for patients with residual disease in future trials.

Treatment of Early Breast Cancer: The 18th St. Gallen International Breast Cancer Consensus Conference against the Background of Current German Treatment Recommendations.

This year's 18th St. Gallen (SG) consensus conference on the treatment of early breast cancer (SGBCC: St. Gallen International Breast Cancer Conference) focused on practice-oriented questions. The individual situation and risk-benefit assessment were discussed in great detail. As in previous years, a German working group of leading breast cancer experts presented the results of the international SGBCC 2023 against the background of German treatment recommendations - especially the updated treatment recommendations of the Arbeitsgemeinschaft Gynäkologische Onkologie e. V. (AGO) - for everyday clinical practice in Germany. The German treatment recommendations of AGO are based on the current evidence. The comparison with the clinical approach in Germany has proven useful, as the SGBCC panel consists of experts from different countries and disciplines. That is why country-specific characteristics can be incorporated into the SGBCC recommendations.

Caveolin Gene Expression Predicts Clinical Outcomes for Early-Stage HER2-Negative Breast Cancer Treated with Paclitaxel-Based Chemotherapy in the GeparSepto Trial.

PURPOSE: Caveolin-1 and -2 (CAV1/2) dysregulation are implicated in driving cancer progression and may predict response to nab-paclitaxel. We explored the prognostic and predictive potential of CAV1/2 expression for patients with early-stage HER2-negative breast cancer receiving neoadjuvant paclitaxel-based chemotherapy regimens, followed by epirubicin and cyclophosphamide. EXPERIMENTAL DESIGN: We correlated tumor CAV1/2 RNA expression with pathologic complete response (pCR), disease-free survival (DFS), and overall survival (OS) in the GeparSepto trial, which randomized patients to neoadjuvant paclitaxel- versus nab-paclitaxel-based chemotherapy. RESULTS: RNA sequencing data were available for 279 patients, of which 74 (26.5%) were hormone receptor (HR)-negative, thus triple-negative breast cancer (TNBC). Patients treated with nab-paclitaxel with high CAV1/2 had higher probability of obtaining a pCR [CAV1 OR, 4.92; 95% confidence interval (CI), 1.70-14.22; P = 0.003; CAV2 OR, 5.39; 95% CI, 1.76-16.47; P = 0.003] as compared with patients with high CAV1/2 treated with solvent-based paclitaxel (CAV1 OR, 0.33; 95% CI, 0.11-0.95; P = 0.040; CAV2 OR, 0.37; 95% CI, 0.12-1.13; P = 0.082). High CAV1 expression was significantly associated with worse DFS and OS in paclitaxel-treated patients (DFS HR, 2.29; 95% CI, 1.08-4.87; P = 0.030; OS HR, 4.97; 95% CI, 1.73-14.31; P = 0.003). High CAV2 was associated with worse DFS and OS in all patients (DFS HR, 2.12; 95% CI, 1.23-3.63; P = 0.006; OS HR, 2.51; 95% CI, 1.22-5.17; P = 0.013), in paclitaxel-treated patients (DFS HR, 2.47; 95% CI, 1.12-5.43; P = 0.025; OS HR, 4.24; 95% CI, 1.48-12.09; P = 0.007) and in patients with TNBC (DFS HR, 4.68; 95% CI, 1.48-14.85; P = 0.009; OS HR, 10.43; 95% CI, 1.22-89.28; P = 0.032). CONCLUSIONS: Our findings indicate high CAV1/2 expression is associated with worse DFS and OS in paclitaxel-treated patients. Conversely, in nab-paclitaxel-treated patients, high CAV1/2 expression is associated with increased pCR and no significant detriment to DFS or OS compared with low CAV1/2 expression.

Prevalence of Pathogenic Germline Variants in Women with Non-Familial Unilateral Triple-Negative Breast Cancer.

Introduction: International guidelines recommend genetic testing for women with familial breast cancer at an expected prevalence of pathogenic germline variants (PVs) of at least 10%. In a study sample of the German Consortium for Hereditary Breast and Ovarian Cancer (GC-HBOC), we have previously shown that women with TNBC diagnosed before the age of 50 years but without a family history of breast or ovarian cancer (sTNBC) meet this criterion. The present study investigates the PV prevalence in BRCA1, BRCA2, and nine additional cancer predisposition genes in an extended sTNBC study sample including a cohort of women with a later age at sTNBC diagnosis. Patients and Methods: In 1,600 women with sTNBC (median age at diagnosis: 41 years, range 19-78 years), we investigated the association between age at diagnosis and PV occurrence in cancer predisposition genes using logistic regression. Results: 260 sTNBC patients (16.2%) were found to have a PV in cancer predisposition genes (BRCA1: n = 170 [10.6%]; BRCA2: n = 46 [2.9%], other: n = 44 [2.8%]). The PV prevalence in women diagnosed between 50 and 59 years (n = 194) was 11.3% (22/194). Logistic regression showed a significant increase in PV prevalence with decreasing age at diagnosis (OR 1.41 per 10 years younger age at diagnosis; 95% confidence interval: 1.21-1.65; p < 0.001). The PV prevalence predicted by the model was above 10% for diagnoses before the age of 56.8 years. Conclusion: Based on the data presented, we recommend genetic testing by gene panel analysis for sTNBC patients diagnosed before the age of 60 years. Due to the still uncertain estimate for women with sTNBC diagnosed above the age of 60 years, further studies are needed.

Inferred Immune-Cell Activity Is an Independent Predictor of HER2-Negative Breast Cancer Prognosis and Response to Paclitaxel-Based Therapy in the GeparSepto Trial.

PURPOSE: Tumor microenvironment (TME) immune markers have been correlated with both response to neoadjuvant therapy and prognosis in patients with breast cancer. Here, immune-cell activity of breast cancer tumors was inferred by expression-based analysis to determine if it is prognostic and/or predictive of response to neoadjuvant paclitaxel-based therapy in the GeparSepto (G7) trial (NCT01583426). EXPERIMENTAL DESIGN: Pre-study biopsies from 279 patients with HER2-negative breast cancer in the G7 trial underwent RNA-seq-based profiling of 104 immune-cell-specific genes to assess inferred Immune Cell Activity (iICA) of 23 immune-cell types. Hierarchical clustering was used to classify tumors as iICA "hot," "warm," or "cold" by comparison of iICA in the G7 cohort relative to that of 1,467 samples from a tumor database established by Nantomics LLC. Correlations between iICA cluster, pathology-assessed tumor-infiltrating lymphocytes (TIL), and hormone receptor (HR) status for pathologic complete response (pCR), disease-free survival (DFS), and overall survival (OS) were determined. RESULTS: iICA cluster correlated with TIL levels. The highest pCR rates were observed in hot cluster tumors, and those with relatively higher TILs. Greater inferred activity of several T-cell types was significantly associated with pCR and survival. DFS and OS were prolonged in patients with hot or warm cluster tumors, the latter particularly for HR negative tumors, even if TILs were relatively low. CONCLUSIONS: Overall, TIL level better predicted pCR, but iICA cluster better predicted survival. Differences in associations between TILs, cluster, pCR, and survival were observed for HR-positive tumors versus HR-negative tumors, suggesting expanded study of the implication of these findings is warranted.

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.

Pathologic Complete Response and Individual Patient Prognosis After Neoadjuvant Chemotherapy Plus Anti-Human Epidermal Growth Factor Receptor 2 Therapy of Human Epidermal Growth Factor Receptor 2-Positive Early Breast Cancer.

PURPOSE: The achievement of pathologic complete response (pCR) is strongly prognostic for event-free survival (EFS) and overall survival (OS) in patients with early breast cancer (EBC), and adapting postneoadjuvant therapy improves long-term outcomes for patients with HER2-positive disease not achieving pCR. We sought to investigate prognostic factors for EFS and OS among patients with and without pCR after neoadjuvant systemic treatment consisting of chemotherapy plus anti-HER2 therapy. MATERIALS AND METHODS: We used individual data from 3,710 patients randomly assigned in 11 neoadjuvant trials for HER2-positive EBC with ≥100 patients enrolled, available data for pCR, EFS, and OS, and follow-up ≥3 years. We assessed baseline clinical tumor size (cT) and clinical nodal status (cN) as prognostic factors using stratified (by trial and treatment) Cox models separately for hormone receptor-positive versus hormone receptor-negative disease, and for patients who had pCR (pCR+; ypT0/is, ypN0) versus patients who did not achieve a pCR (pCR-). RESULTS: The median follow-up overall was 61.2 months. In pCR+ patients, cT and cN were significant independent prognostic factors for EFS, whereas only cT was a significant predictor for OS. In pCR- patients, cT, cN, and hormone receptor status were significant independent predictors for both EFS and OS. Regardless of hormone receptor status, cT, and cN, the 5-year EFS/OS rates were higher in pCR+ patients than in pCR- patients. In most subsets with regards to hormone receptor and pCR status, cT and cN were independent prognostic factors for both EFS and OS, including pCR+ patients. CONCLUSION: These results confirm that patients achieving pCR have far better survival outcomes than patients who do not. The traditional poor prognostic features, namely tumor size and nodal status, remain important even after a pCR.

Re-Evaluation of Pathologic Complete Response as a Surrogate for Event-Free and Overall Survival in Human Epidermal Growth Factor Receptor 2-Positive, Early Breast Cancer Treated With Neoadjuvant Therapy Including Anti-Human Epidermal Growth Factor Receptor 2 Therapy.

PURPOSE: Pathologic complete response (pCR) has prognostic importance and is frequently used as a primary end point, but doubts remain about its validity as a surrogate for event-free survival (EFS) and overall survival (OS) in human epidermal growth factor receptor 2 (HER2)-positive, early breast cancer. METHODS: We obtained individual-patient data from randomized trials of neoadjuvant anti-HER2 therapy that enrolled at least 100 patients, had data for pCR, EFS, and OS, and a median follow-up of at least 3 years. We quantified the patient-level association between pCR (defined as ypT0/Tis ypN0) and both EFS and OS using odds ratios (ORs, with ORs >1.00 indicating a benefit from achieving a pCR). We quantified the trial-level association between treatment effects on pCR and on EFS and OS using R2 (with values above 0.75 considered as indicating strong associations). RESULTS: Eleven of 15 eligible trials had data for analysis (3,980 patients, with a median follow-up of 62 months). Considering all trials, we found strong patient-level associations, with ORs of 2.64 (95% CI, 2.20 to 3.07) for EFS and 3.15 (95% CI, 2.38 to 3.91) for OS; however, trial-level associations were weak, with an unadjusted R2 of 0.23 (95% CI, 0 to 0.66) for EFS and 0.02 (95% CI, 0 to 0.17) for OS. We found qualitatively similar results when grouping trials according to different clinical questions, when analyzing only patients with hormone receptor-negative disease, and when using a more stringent definition of pCR (ypT0 ypN0). CONCLUSION: Although pCR may be useful for patient management, it cannot be considered as a surrogate for EFS or OS in neoadjuvant trials of HER2-positive, operable breast cancer.

Characterization of Hormone Receptor and HER2 Status in Breast Cancer Using Mass Spectrometry Imaging.

Immunohistochemical evaluation of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor-2 status stratify the different subtypes of breast cancer and define the treatment course. Triple-negative breast cancer (TNBC), which does not register receptor overexpression, is often associated with worse patient prognosis. Mass spectrometry imaging transcribes the molecular content of tissue specimens without requiring additional tags or preliminary analysis of the samples, being therefore an excellent methodology for an unbiased determination of tissue constituents, in particular tumor markers. In this study, the proteomic content of 1191 human breast cancer samples was characterized by mass spectrometry imaging and the epithelial regions were employed to train and test machine-learning models to characterize the individual receptor status and to classify TNBC. The classification models presented yielded high accuracies for estrogen and progesterone receptors and over 95% accuracy for classification of TNBC. Analysis of the molecular features revealed that vimentin overexpression is associated with TNBC, supported by immunohistochemistry validation, revealing a new potential target for diagnosis and treatment.

EVI1 expression in early-stage breast cancer patients treated with neoadjuvant chemotherapy.

BACKGROUND: Overexpression of the EVI1 (ecotropic viral integration site 1) oncogene has recently been implicated as a prognostic factor in breast cancer (BC), particularly in triple-negative BC (TNBC). In this study we aimed to investigate frequency and clinical relevance of EVI1 expression in newly diagnosed BC treated with neoadjuvant chemotherapy. METHODS: EVI1 expression was determined by immunohistochemistry using H-score as a cumulative measurement of protein expression in pretherapeutic biopsies of BC patients treated with anthracycline/taxane based neoadjuvant chemotherapy within the GeparTrio trial. EVI1 was analyzed as a continuous variable and dichotomized into low or high based on median expression. Endpoints were pathological complete response (pCR), disease-free survival (DFS) and overall survival (OS). RESULTS: Of the 993 tumors analyzed, 882 had available subtype information: 50.8% were HR + /HER2-, 15% HR + /HER2 + , 9.8% HR-/HER2 + , and 24.5% TNBC. Median EVI1 H-score was 112.16 (range 0.5-291.4). High EVI1 expression was significantly associated with smaller tumor size (p = 0.002) but not with BC subtype. Elevated EVI1 levels were not significantly associated with therapy response and survival in the entire cohort or within BC subtypes. However, TNBC patients with high EVI1 showed a trend towards increased pCR rates compared to low group (37.7% vs 27.5%, p = 0.114; odds ratio 1.60 (95%CI 0.90-2.85, p = 0.110) and numerically better DFS (HR = 0.77 [95%CI 0.48-1.23], log-rank p = 0.271) and OS (HR = 0.76 [95% 0.44-1.31], log-rank p = 0.314) without reaching statistical significance. CONCLUSION: EVI1 was not associated with response to neoadjuvant therapy or patient survival in the overall cohort. Further analyses are needed to verify our findings especially in the pathological work-up of early-stage HER2-negative BC patients. TRIAL REGISTRATION: NCT00544765.

Effects of capecitabine as part of neo-/adjuvant chemotherapy - A meta-analysis of individual breast cancer patient data from 13 randomised trials including 15,993 patients.

BACKGROUND: Despite the large number of patients with early breast cancer (EBC) who have been treated with capecitabine in randomised trials, no individual patient data meta-analysis has been conducted. The primary objective was to examine the effect of capecitabine on disease-free survival (DFS), and the secondary objectives were to analyse distant DFS (DDFS), overall survival (OS), pathological complete response (for neoadjuvant studies) and the interaction between capecitabine-related toxicity and treatment effect. METHODS: www. CLINICALTRIALS: gov and www.pubmed.ncbi.nlm.nih.gov were searched using the following criteria: use of capecitabine for EBC as adjuvant or neoadjuvant therapy; multicentre randomised trial with >100 patients; recruitment completed, and outcomes available. Required data were available for 13 trials. RESULTS: Individual data from 15,993 patients were collected. Cox regression analyses of all included patients revealed that the addition of capecitabine did not alter DFS significantly compared with treatment without capecitabine (hazard ratio [HR] 0.952; 95% CI 0.895-1.012; P value = 0.115). There was also no effect on DFS in the subset of studies where capecitabine was given instead of another drug (HR 1.035; 95% CI 0.945-1.134; P = 0.455). However, capecitabine administered in addition to the standard systemic treatment improved DFS (HR 0.888; 95% CI 0.817-0.965; P = 0.005). An OS improvement was observed in the entire cohort (HR 0.892; 95% CI 0.824-0.965, P = 0.005) and in the subset of capecitabine addition (HR 0.837; 95% CI 0.751, 0.933, P = 0.001). Subgroup analyses revealed that triple-negative breast cancer (TNBC) patients benefitted from treatment with capecitabine overall and in addition to other systemic treatments in terms of DFS and OS. CONCLUSION: Capecitabine was able to improve DFS and OS in patients with TNBC and in all patients with EBC when administered in addition to systemic treatment.

Intelligent Vacuum-Assisted Biopsy to Identify Breast Cancer Patients With Pathologic Complete Response (ypT0 and ypN0) After Neoadjuvant Systemic Treatment for Omission of Breast and Axillary Surgery.

PURPOSE: Neoadjuvant systemic treatment (NST) elicits a pathologic complete response in 40%-70% of women with breast cancer. These patients may not need surgery as all local tumor has already been eradicated by NST. However, nonsurgical approaches, including imaging or vacuum-assisted biopsy (VAB), were not able to accurately identify patients without residual cancer in the breast or axilla. We evaluated the feasibility of a machine learning algorithm (intelligent VAB) to identify exceptional responders to NST. METHODS: We trained, tested, and validated a machine learning algorithm using patient, imaging, tumor, and VAB variables to detect residual cancer after NST (ypT+ or in situ or ypN+) before surgery. We used data from 318 women with cT1-3, cN0 or +, human epidermal growth factor receptor 2-positive, triple-negative, or high-proliferative Luminal B-like breast cancer who underwent VAB before surgery (ClinicalTrials.gov identifier: NCT02948764, RESPONDER trial). We used 10-fold cross-validation to train and test the algorithm, which was then externally validated using data of an independent trial (ClinicalTrials.gov identifier: NCT02575612). We compared findings with the histopathologic evaluation of the surgical specimen. We considered false-negative rate (FNR) and specificity to be the main outcomes. RESULTS: In the development set (n = 318) and external validation set (n = 45), the intelligent VAB showed an FNR of 0.0%-5.2%, a specificity of 37.5%-40.0%, and an area under the receiver operating characteristic curve of 0.91-0.92 to detect residual cancer (ypT+ or in situ or ypN+) after NST. Spiegelhalter's Z confirmed a well-calibrated model (z score -0.746, P = .228). FNR of the intelligent VAB was lower compared with imaging after NST, VAB alone, or combinations of both. CONCLUSION: An intelligent VAB algorithm can reliably exclude residual cancer after NST. The omission of breast and axillary surgery for these exceptional responders may be evaluated in future trials.

mdm2 gene amplification is associated with luminal breast cancer progression in humanized PDX mice and a worse outcome of estrogen receptor positive disease.

Estrogen receptor-positive breast cancer is a highly prevalent but heterogeneous disease among women. Advanced molecular stratification is required to enable individually most efficient treatments based on relevant prognostic and predictive biomarkers. First objective of our study was the hypothesis-driven discovery of biomarkers involved in tumor progression upon xenotransplantation of Luminal breast cancer into humanized mice. The second objective was the marker validation and correlation with the clinical outcome of Luminal breast cancer disease within the GeparTrio trial. An elevated mdm2 gene copy number was associated with enhanced tumor growth and lung metastasis in humanized tumor mice. The viability, proliferation and migration capacity of inherently mdm2 positive breast cancer cells in vitro were significantly reduced upon mdm2 knockdown or anti-mdm2 targeting. An mdm2 gain significantly correlated with a worse DFS and OS of Luminal breast cancer patients, albeit it was also associated with an enhanced preoperative pathological response rate. We provide evidence for an enhanced Luminal breast cancer stratification based on mdm2. Moreover, mdm2 can potentially be utilized as a therapeutic target in the Luminal subtype.