Circulating tumor DNA for predicting recurrence in patients with operable breast cancer: a systematic review and meta-analysis.

BACKGROUND: The incorporation of circulating tumor DNA (ctDNA) into the management of operable breast cancer (BC) has been hampered by the heterogeneous results from different studies. We aimed to assess the prognostic value of ctDNA in patients with operable (non metastatic) BC. MATERIALS AND METHODS: A systematic search of databases (PubMed/Medline, Embase, and CENTRAL) and conference proceedings was conducted to identify studies reporting the association of ctDNA detection with disease-free survival (DFS) and overall survival (OS) in patients with stage I-III BC. Log-hazard ratios (HRs) were pooled at each timepoint of ctDNA assessment (baseline, after neoadjuvant therapy, and follow-up). ctDNA assays were classified as primary tumor-informed and non tumor-informed. RESULTS: Of the 3174 records identified, 57 studies including 5779 patients were eligible. In univariate analyses, ctDNA detection was associated with worse DFS at baseline [HR 2.98, 95% confidence interval (CI) 1.92-4.63], after neoadjuvant therapy (HR 7.69, 95% CI 4.83-12.24), and during follow-up (HR 14.04, 95% CI 7.55-26.11). Similarly, ctDNA detection at all timepoints was associated with worse OS (at baseline: HR 2.76, 95% CI 1.60-4.77; after neoadjuvant therapy: HR 2.72, 95% CI 1.44-5.14; and during follow-up: HR 9.19, 95% CI 3.26-25.90). Similar DFS and OS results were observed in multivariate analyses. Pooled HRs were numerically higher when ctDNA was detected at the end of neoadjuvant therapy or during follow-up and for primary tumor-informed assays. ctDNA detection sensitivity and specificity for BC recurrence ranged from 0.31 to 1.0 and 0.7 to 1.0, respectively. The mean lead time from ctDNA detection to overt recurrence was 10.81 months (range 0-58.9 months). CONCLUSIONS: ctDNA detection was associated with worse DFS and OS in patients with operable BC, particularly when detected after treatment and using primary tumor-informed assays. ctDNA detection has a high specificity for anticipating BC relapse.

How I treat endocrine-dependent metastatic breast cancer.

Estrogen receptor-positive (ER+)/HER2-negative (HER2-), the so-called luminal-type breast cancer, is the most frequent subset, accounting for around 70% of all breast cancer cases. Endocrine therapy (ET) combined with cyclin-dependent kinases (CDK) 4/6 inhibitors is the standard first option in the management of advanced luminal breast cancer independently of disease extension. Classically, patients undergo multiple lines of ET ± targeted treatments until endocrine resistance occurs and palliative chemotherapy is proposed. Understanding endocrine resistance mechanisms and development of novel ET options is one of the main challenges in current clinical research. Another area of utmost interest is the improvement of post-endocrine therapeutic approaches. Among others, the development of antibody-drug conjugates (ADCs) is very promising, and some of these drugs will probably soon become a part of the therapeutic arsenal against this incurable disease. This review paper provides an overview of currently available treatment options in ER+/HER2- metastatic breast cancer and extensively discusses new approaches in late clinical development.

Changes in anticancer treatment plans in patients with solid cancer hospitalized with COVID-19: analysis of the nationwide BSMO-COVID registry providing lessons for the future.

BACKGROUND: Solid cancer is an independent prognostic factor for poor outcome with COVID-19. As guidelines for patient management in that setting depend on retrospective efforts, we here present the first analyses of a nationwide database of patients with cancer hospitalized with COVID-19 in Belgium, with a focus on changes in anticancer treatment plans at the time of SARS-CoV-2 infection. METHODS: Nineteen Belgian hospitals identified all patients with a history of solid cancer hospitalized with COVID-19 between March 2020 and February 2021. Demographic, cancer-specific and COVID-specific data were pseudonymously entered into a central Belgian Society of Medical Oncology (BSMO)-COVID database. The association between survival and primary cancer type was analyzed through multivariate multinomial logistic regression. Group comparisons for categorical variables were carried out through a Chi-square test. RESULTS: A total of 928 patients were registered in the database; most of them were aged ≥70 years (61.0%) and with poor performance scores [57.2% Eastern Cooperative Oncology Group (ECOG) ≥2]. Thirty-day COVID-related mortality was 19.8%. In multivariate analysis, a trend was seen for higher mortality in patients with lung cancer (27.6% versus 20.8%, P = 0.062) and lower mortality for patients with breast cancer (13.0% versus 23.3%, P = 0.052) compared with other tumour types. Non-curative treatment was associated with higher 30-day COVID-related mortality rates compared with curative or no active treatment (25.8% versus 14.3% versus 21.9%, respectively, P < 0.001). In 33% of patients under active treatment, the therapeutic plan was changed due to COVID-19 diagnosis, most frequently involving delays/interruptions in systemic treatments (18.6%). Thirty-day COVID-related mortality was not significantly different between patients with and without treatment modifications (21.4% versus 20.5%). CONCLUSION: Interruption in anticancer treatments at the time of SARS-CoV-2 infection was not associated with a reduction in COVID-related mortality in our cohort of patients with solid cancer, highlighting that treatment continuation should be strived for, especially in the curative setting.

Predictive factors for cancer-associated thrombosis in a large retrospective single-center study.

BACKGROUND: The relationship between cancer and thrombosis has been studied for years, but reliable guidelines for thromboprophylaxis in that situation are still unclear. METHODS: We retrospectively reviewed the files of 3159 consecutive patients with newly diagnosed solid tumors at Jules Bordet Institute from January 2008 to December 2011. Among them, 99 developed a symptomatic thromboembolic episode and were matched with 2 controls (nested case control). The aim was to identify risk factors of thromboembolic events and to validate in our setting the Khorana score. RESULTS: In the cohort study, nodal status ≥ 2, presence of metastases, and primary tumor site were found to be the most significant predictive factors of a thromboembolic event (n = 99; 3.1%) in the multivariate analysis. In the nested study (n = 265), hemoglobin < 13 g/dL or treatment with a red cell growth factor, CRP ≥ 31.6 mg/L, creatinine level > 0.96 mg/dL, chronic inflammatory disease, and personal or familial history of thromboembolic events were found to be the most significant predictive factors of a thromboembolic event in the multivariate analysis. In our population, the sensitivity, specificity, positive predictive value, and negative predictive value of the Khorana score were respectively 29%, 93%, 15%, and 96%. CONCLUSION: We confirm the value of the risk factors identified in the literature with the additional presence of nodal involvement, elevated CRP, and creatinine levels, which may be helpful for patient risk stratification and should be considered in future clinical trials. Our results also suggest that the Khorana score might help to identify patients who can safely be spared of thromboprophylaxis.

Trastuzumab versus observation for HER2 nonamplified early breast cancer with circulating tumor cells (EORTC 90091-10093, BIG 1-12, Treat CTC): a randomized phase II trial.

Background: Trastuzumab improves the outcome of women with HER2 positive breast cancer. We aimed to assess whether trastuzumab decreases the detection rate of circulating tumor cells (CTCs) in women with high risk, HER2 nonamplified, early breast cancer. Patients and methods: The EORTC 90091-10093 BIG 1-12 Treat CTC is a phase II trial, conducted in 70 hospitals and 6 CTC laboratories across 5 European countries. Patients with centrally confirmed HER2 nonamplified breast cancer and ≥1 centrally confirmed CTC per 15 ml of blood by CellSearch® following surgery and (neo)adjuvant chemotherapy were randomized (1 : 1) to 6 cycles of trastuzumab intravenously versus 18 weeks of observation. Randomization was stratified for center, locally confirmed estrogen receptor status and adjuvant versus neoadjuvant chemotherapy. The primary end point was rate of detection of ≥1 CTC per 15 ml of blood at week 18. Secondary end points were invasive disease-free survival (iDFS) and cardiac safety. Results: Between 30 April 2013 and 17 October 2016, 1317 patients were screened; 95 (7.2%) had detectable CTC(s), and 63 (4.8%) were randomized to trastuzumab (n = 31) or observation (n = 32). Fifty-eight patients were assessable for the primary end point, 29 in each arm. In 9 of the 58 patients, CTC(s) were still detected at week 18 : 5 in the trastuzumab and 4 in the observation arm (one-sided Fisher's exact test, P = 0.765). An Independent Data Monitoring Committee recommended stopping further accrual for futility for the primary end point. Median follow-up at database lock was 13 months (IQR 4-16.5). The 1-year iDFS was 93.8% (95% CI 77.3-98.4) in the observation versus 84.8% (95% CI 63.4-94.2) in the trastuzumab arm. No grade 2-4 cardiac events were observed in the trastuzumab arm. Conclusion: Trastuzumab does not decrease the detection rate of CTCs in HER2 nonamplified, nonmetastatic breast cancer.

Unravelling triple-negative breast cancer molecular heterogeneity using an integrative multiomic analysis.

Background: Recent efforts of genome-wide gene expression profiling analyses have improved our understanding of the biological complexity and diversity of triple-negative breast cancers (TNBCs) reporting, at least six different molecular subtypes of TNBC namely Basal-like 1 (BL1), basal-like 2 (BL2), immunomodulatory (IM), mesenchymal (M), mesenchymal stem-like (MSL) and luminal androgen receptor (LAR). However, little is known regarding the potential driving molecular events within each subtype, their difference in survival and response to therapy. Further insight into the underlying genomic alterations is therefore needed. Patients and methods: This study was carried out using copy-number aberrations, somatic mutations and gene expression data derived from the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) and The Cancer Genome Atlas. TNBC samples (n = 550) were classified according to Lehmann's molecular subtypes using the TNBCtype online subtyping tool (http://cbc.mc.vanderbilt.edu/tnbc/). Results: Each subtype showed significant clinic-pathological characteristic differences. Using a multivariate model, IM subtype showed to be associated with a better prognosis (HR = 0.68; CI = 0.46-0.99; P = 0.043) whereas LAR subtype was associated with a worst prognosis (HR = 1.47; CI = 1.0-2.14; P = 0.046). BL1 subtype was found to be most genomically instable subtype with high TP53 mutation (92%) and copy-number deletion in genes involved in DNA repair mechanism (BRCA2, MDM2, PTEN, RB1 and TP53). LAR tumours were associated with higher mutational burden with significantly enriched mutations in PI3KCA (55%), AKT1 (13%) and CDH1 (13%) genes. M and MSL subtypes were associated with higher signature score for angiogenesis. Finally, IM showed high expression levels of immune signatures and check-point inhibitor genes such as PD1, PDL1 and CTLA4. Conclusion: Our findings highlight for the first time the substantial genomic heterogeneity that characterize TNBC molecular subtypes, allowing for a better understanding of the disease biology as well as the identification of several candidate targets paving novel approaches for the development of anticancer therapeutics for TNBC.

Reproductive potential and performance of fertility preservation strategies in BRCA-mutated breast cancer patients.

Background: Preclinical evidence suggests a possible negative impact of deleterious BRCA mutations on female fertility. However, limited and rather conflicting clinical data are available. This study assessed the reproductive potential and performance of fertility preservation strategies in BRCA-mutated breast cancer patients. Patients and methods: This was a retrospective analysis of two prospective studies investigating oocyte cryopreservation and ovarian tissue cryopreservation in newly diagnosed early breast cancer patients. In the current analysis, baseline anti-Mullerian hormone (AMH) and performance of cryopreservation strategies were compared between patients with or without germline deleterious BRCA mutations. Results: Out of 156 patients included, 101 had known BRCA status of whom 29 (18.6%) were BRCA-mutated and 72 (46.1%) had no mutation. Median age in the entire cohort was 31 years [interquartile range (IQR) 28-33). Median AMH levels were 1.8 µg/l (IQR 1.0-2.7) and 2.6 µg/l (IQR 1.5-4.1) in the BRCA-positive and BRCA-negative cohorts, respectively (P = 0.109). Among patients who underwent oocyte cryopreservation (N = 29), women in the BRCA-positive cohort tended to retrieve (6.5 versus 9; P = 0.145) and to cryopreserve (3.5 versus 6; P = 0.121) less oocytes than those in the BRCA-negative cohort. Poor response rate (i.e. retrieval of ≤4 oocytes) was 40.0% and 11.1% in the BRCA-positive and BRCA-negative cohorts, respectively (P = 0.147). Among patients who underwent ovarian tissue cryopreservation (N = 72), women in the BRCA-positive cohort tended to have a numerically lower number of oocytes per fragment (0.08 versus 0.14; P = 0.193) and per square millimeter (0.33 versus 0.78; P = 0.153) than those in the BRCA-negative cohort. Two BRCA-mutated patients were transplanted after chemotherapy and one delivered at term a healthy baby. No difference between BRCA1- and BRCA2-mutated patients was observed in any of the above-mentioned outcomes. Conclusion: A consistent trend for reduced reproductive potential and performance of cryopreservation strategies was observed in BRCA-mutated breast cancer patients. Independent validation of these results is needed.

Tumor-infiltrating lymphocytes in patients with HER2-positive breast cancer treated with neoadjuvant chemotherapy plus trastuzumab, lapatinib or their combination: A meta-analysis of randomized controlled trials.

BACKGROUND: A relationship between baseline tumor-infiltrating lymphocytes (TIL) and outcomes has been described in HER2-positive breast cancer. Nevertheless, the magnitude of this association and whether this effect differs based on the type of anti-HER2 agent remain controversial. This meta-analysis investigated the association between baseline TIL and pathologic complete response (pCR) rates in HER2-positive breast cancer patients treated with neoadjuvant chemotherapy plus trastuzumab and lapatinib either alone or in combination. METHODS: A literature search covering PubMed, Embase and the Cochrane library up to October 31, 2016 identified randomized, controlled trials investigating neoadjuvant chemotherapy plus trastuzumab and lapatinib either alone or in combination where published data for pCR based on pre-treatment TIL scores were available. Two subgroups were considered: high baseline TIL vs. non-high TIL, according to each study definition. Summary risk estimates (odds ratio) and 95% confidence intervals (CI) were calculated for pCR using pre-treatment TIL levels for each trial. Pooled analyses were conducted using random and fixed effects models. Interaction P-values were computed using a Monte Carlo permutation test. RESULTS: A total of 5 studies (N=1256 patients) were included. Overall, high TIL subgroup was associated with a significantly increased pCR rate (OR 2.46; 95% CI 1.36-4.43; P=0.003). No interaction was observed between TIL subgroup (high vs. non-high TIL) and response to anti-HER2 agent(s) (trastuzumab vs. lapatinib vs. their combination; P=0.747) and chemotherapy (anthracycline and taxanes vs. taxanes only; P=0.201). A stronger association between high TIL subgroup and pCR rates was observed when examining only the 4 studies using anthracycline- and taxane- based neoadjuvant chemotherapy and the 60% cut-off for high TIL (N=869, NeoALTTO excluded) with an OR of 2.88 (95% CI 2.03-4.08; P<0.001). CONCLUSIONS: In HER2-positive breast cancer, high baseline TIL are associated with increased pCR probability irrespective of neoadjuvant anti-HER2 agent(s) and chemotherapy regimens used.

The current use and attitudes towards tumor genome sequencing in breast cancer.

There is increasing availability of technologies that can interrogate the genomic landscape of an individual tumor; however, their impact on daily practice remains uncertain. We conducted a 28-item survey to investigate the current attitudes towards the integration of tumor genome sequencing in breast cancer management. A link to the survey was communicated via newsletters of several oncological societies, and dedicated mailing by academic research groups. Multivariable logistic regression modeling was carried out to determine the relationship between predictors and outcomes. 215 physicians participated to the survey. The majority were medical oncologists (88%), practicing in Europe (70%) and working in academic institutions (66%). Tumor genome sequencing was requested by 82 participants (38%), of whom 21% reported low confidence in their genomic knowledge, and 56% considered tumor genome sequencing to be poorly accessible. In multivariable analysis, having time allocated to research (OR 3.37, 95% CI 1.84-6.15, p < 0.0001), working in Asia (OR 5.76, 95% CI 1.57 - 21.15, p = 0.01) and having institutional guidelines for molecular sequencing (OR 2.09, 95% 0.99-4.42, p = 0.05) were associated with a higher probability of use. In conclusion, our survey indicates that tumor genome sequencing is sometimes used, albeit not widely, in guiding management of breast cancer patients.

The evaluation of tumor-infiltrating lymphocytes (TILs) in breast cancer: recommendations by an International TILs Working Group 2014.

BACKGROUND: The morphological evaluation of tumor-infiltrating lymphocytes (TILs) in breast cancer (BC) is gaining momentum as evidence strengthens for the clinical relevance of this immunological biomarker. Accumulating evidence suggests that the extent of lymphocytic infiltration in tumor tissue can be assessed as a major parameter by evaluation of hematoxylin and eosin (H&E)-stained tumor sections. TILs have been shown to provide prognostic and potentially predictive value, particularly in triple-negative and human epidermal growth factor receptor 2-overexpressing BC. DESIGN: A standardized methodology for evaluating TILs is now needed as a prerequisite for integrating this parameter in standard histopathological practice, in a research setting as well as in clinical trials. This article reviews current data on the clinical validity and utility of TILs in BC in an effort to foster better knowledge and insight in this rapidly evolving field, and to develop a standardized methodology for visual assessment on H&E sections, acknowledging the future potential of molecular/multiplexed approaches. CONCLUSIONS: The methodology provided is sufficiently detailed to offer a uniformly applied, pragmatic starting point and improve consistency and reproducibility in the measurement of TILs for future studies.

Circulating tumor cells and circulating tumor DNA for precision medicine: dream or reality?

Next-generation sequencing studies have provided further evidence to support the notion that cancer is a disease characterized by Darwinian evolution. Today, we often fail to capture this evolution and treatment decisions, even in the metastatic setting, are often based on analysis of primary tumor diagnosed years ago. Currently, this is considered a major reason for treatment failures in cancer care. Recent technological advances in the detection and characterization of circulating tumor cells and circulating tumor DNA might address this and allow for treatment tailoring based on real-time monitoring of tumor evolution. In this review, we summarize the most important recent findings in the field, focusing on challenges and opportunities in moving these tools forward in clinical practice.

Plasma circulating tumor DNA as an alternative to metastatic biopsies for mutational analysis in breast cancer.

BACKGROUND: Molecular screening programs use next-generation sequencing (NGS) of cancer gene panels to analyze metastatic biopsies. We interrogated whether plasma could be used as an alternative to metastatic biopsies. PATIENTS AND METHODS: The Ion AmpliSeq™ Cancer Hotspot Panel v2 (Ion Torrent), covering 2800 COSMIC mutations from 50 cancer genes was used to analyze 69 tumor (primary/metastases) and 31 plasma samples from 17 metastatic breast cancer patients. The targeted coverage for tumor DNA was ×1000 and for plasma cell-free DNA ×25 000. Whole blood normal DNA was used to exclude germline variants. The Illumina technology was used to confirm observed mutations. RESULTS: Evaluable NGS results were obtained for 60 tumor and 31 plasma samples from 17 patients. When tumor samples were analyzed, 12 of 17 (71%, 95% confidence interval (CI) 44% to 90%) patients had ≥1 mutation (median 1 mutation per patient, range 0-2 mutations) in either p53, PIK3CA, PTEN, AKT1 or IDH2 gene. When plasma samples were analyzed, 12 of 17 (71%, 95% CI: 44-90%) patients had ≥1 mutation (median 1 mutation per patient, range 0-2 mutations) in either p53, PIK3CA, PTEN, AKT1, IDH2 and SMAD4. All mutations were confirmed. When we focused on tumor and plasma samples collected at the same time-point, we observed that, in four patients, no mutation was identified in either tumor or plasma; in nine patients, the same mutations was identified in tumor and plasma; in two patients, a mutation was identified in tumor but not in plasma; in two patients, a mutation was identified in plasma but not in tumor. Thus, in 13 of 17 (76%, 95% CI 50% to 93%) patients, tumor and plasma provided concordant results whereas in 4 of 17 (24%, 95% CI 7% to 50%) patients, the results were discordant, providing complementary information. CONCLUSION: Plasma can be prospectively tested as an alternative to metastatic biopsies in molecular screening programs.

Semiautomated isolation and molecular characterisation of single or highly purified tumour cells from CellSearch enriched blood samples using dielectrophoretic cell sorting.

BACKGROUND: Molecular characterisation of single circulating tumour cells (CTCs) holds considerable promise for predictive biomarker assessment and to explore CTC heterogeneity. We evaluate a new method, the DEPArray system, that allows the dielectrophoretic manipulation and isolation of single and 100% purified groups of CTCs from pre-enriched blood samples and explore the feasibility of their molecular characterisation. METHODS: Samples containing known numbers of two cell populations were used to assess cell loss during sample loading. Cultured breast cancer cells were isolated from spiked blood samples using CellSearch CTC and Profile kits. Single tumour cells and groups of up to 10 tumour cells were recovered with the DEPArray system and subjected to transcriptional and mutation analysis. RESULTS: On average, 40% cell loss was observed when loading samples to the DEPArray system. Expected mutations in clinically relevant markers could be obtained for 60% of single recovered tumour cells and all groups of tumour cells. Reliable gene expression profiles were obtained from single cells and groups of up to 10 cells for 2 out of 3 spiked breast cancer cell lines. CONCLUSION: We describe a semiautomated workflow for the isolation of small groups of 1 to 10 tumour cells from whole blood samples and provide proof of principle for the feasibility of their comprehensive molecular characterisation.