Tumor infiltrating lymphocytes are prognostic in triple negative breast cancer and predictive for trastuzumab benefit in early breast cancer: results from the FinHER trial

Relevance of Tumor-Infiltrating Immune Cell Composition and Functionality for Disease Outcome in Breast Cancer

Background

Not all breast cancer patients benefit from neoadjuvant or adjuvant therapy, resulting in considerable undertreatment or overtreatment. New insights into the role of tumor-infiltrating immune cells suggest that their composition, as well as their functionality, might serve as a biomarker to enable optimal patient selection for current systemic therapies and upcoming treatment options such as immunotherapy.

Methods

We performed several complementary unbiased in silico analyses on gene expression profiles of 7270 unrelated tumor samples of nonmetastatic breast cancer patients with known clinical follow-up. CIBERSORT was used to estimate the fraction of 22 immune cell types to study their relations with pathological complete response (pCR), disease-free survival (DFS), and overall survival (OS). In addition, we used four previously reported immune gene signatures and a CD8+ T-cell exhaustion signature to assess their relationships with breast cancer outcome. Multivariable binary logistic regression and multivariable Cox regression were used to assess the association of immune cell-type fractions and immune signatures with pCR and DFS/OS, respectively.

Results

Increased fraction of regulatory T-cells in human epidermal growth factor receptor 2 (HER2)-positive tumors was associated with a lower pCR rate (odds ratio [OR] = 0.15, 95% confidence interval [CI] = 0.03 to 0.69), as well as shorter DFS (hazard ratio [HR] = 3.13, 95% CI = 1.23 to 7.98) and OS (HR = 7.69, 95% CI = 3.43 to 17.23). A higher fraction of M0 macrophages in estrogen receptor (ER)-positive tumors was associated with worse DFS (HR = 1.66, 95% CI = 1.18 to 2.33) and, in ER-positive/HER2-negative tumors, with worse OS (HR = 1.71, 95% CI = 1.12 to 2.61). Increased fractions of γδ T-cells in all breast cancer patients related to a higher pCR rate (OR = 1.55, 95% CI = 1.01 to 2.38), prolonged DFS (HR = 0.68, 95% CI = 0.48 to 0.98), and, in HER2-positive tumors, with prolonged OS (HR = 0.27, 95% CI = 0.10 to 0.73). A higher fraction of activated mast cells was associated with worse DFS (HR = 5.85, 95% CI = 2.20 to 15.54) and OS (HR = 5.33, 95% CI = 2.04 to 13.91) in HER2-positive tumors. The composition of relevant immune cell types frequently differed per breast cancer subtype. Furthermore, a high CD8+ T-cell exhaustion signature score was associated with shortened DFS in patients with ER-positive tumors regardless of HER2 status (HR = 1.80, 95% CI = 1.07 to 3.04).

Conclusions

The main hypothesis generated in our unbiased in silico approach is that a multitude of immune cells are related to treatment response and outcome in breast cancer.

Prognostic and predictive value of tumor infiltrating lymphocytes in early breast cancer

It is well recognized that the immune system plays an essential role in tumor defense. The presence of tumor-infiltrating lymphocytes reflects an individual immunological response. In early breast cancer, the presence of TILs is associated with a more favorable outcome and response to therapy. In this review, we describe how TILs are assessed. Also, we discuss their role as prognostic and predictive biomarker in the neoadjuvant and adjuvant settings as well as in residual disease. Moreover, we discuss the possible implementation of TILs in daily clinical practice as well as in future clinical trials in order to fine tune prognosis and improve treatments.

TNFα-Induced Mucin 4 Expression Elicits Trastuzumab Resistance in HER2-Positive Breast Cancer

PURPOSE

Although trastuzumab administration improved the outcome of HER2-positive breast cancer patients, resistance events hamper its clinical benefits. We demonstrated that TNFα stimulation in vitro induces trastuzumab resistance in HER2-positive breast cancer cell lines. Here, we explored the mechanism of TNFα-induced trastuzumab resistance and the therapeutic strategies to overcome it.

EXPERIMENTAL DESIGN

Trastuzumab-sensitive breast cancer cells, genetically engineered to stably overexpress TNFα, and de novo trastuzumab-resistant tumors, were used to evaluate trastuzumab response and TNFα-blocking antibodies effectiveness respectively. Immunohistochemistry and antibody-dependent cell cytotoxicity (ADCC), together with siRNA strategy, were used to explore TNFα influence on the expression and function of its downstream target, mucin 4 (MUC4). The clinical relevance of MUC4 expression was studied in a cohort of 78 HER2-positive breast cancer patients treated with adjuvant trastuzumab.

RESULTS

TNFα overexpression turned trastuzumab-sensitive cells and tumors into resistant ones. Histopathologic findings revealed mucin foci in TNFα-producing tumors. TNFα induced upregulation of MUC4 that reduced trastuzumab binding to its epitope and impaired ADCC. Silencing MUC4 enhanced trastuzumab binding, increased ADCC, and overcame trastuzumab and trastuzumab-emtansine antiproliferative effects in TNFα-overexpressing cells. Accordingly, administration of TNFα-blocking antibodies downregulated MUC4 and sensitized de novo trastuzumab-resistant breast cancer cells and tumors to trastuzumab. In HER2-positive breast cancer samples, MUC4 expression was found to be an independent predictor of poor disease-free survival (P = 0.008).

CONCLUSIONS

We identified TNFα-induced MUC4 expression as a novel trastuzumab resistance mechanism. We propose MUC4 expression as a predictive biomarker of trastuzumab efficacy and a guide to combination therapy of TNFα-blocking antibodies with trastuzumab. Clin Cancer Res; 23(3); 636-48. ©2016 AACR.

Tumor Infiltrating Lymphocytes Affect the Outcome of Patients with Operable Triple-Negative Breast Cancer in Combination with Mutated Amino Acid Classes

Background

Stromal tumor infiltrating lymphocytes (TILs) density is an outcome predictor in triple-negative breast cancer (TNBC). Herein we asked whether TILs are related to coding mutation load and to the chemical class of the resulting mutated amino acids, i.e., charged, polar, and hydrophobic mutations.

Methods

We examined paraffin tumors from TNBC patients who had been treated with adjuvant chemotherapy mostly within clinical trials (training cohort, N = 133; validation, N = 190) for phenotype concordance; TILs density; mutation load and types.

Results

Concordance of TNBC phenotypes was 42.1% upon local / central, and 72% upon central / central pathology assessment. TILs were not associated with mutation load, type and class of mutated amino acids. Polar and charged mutation patterns differed between TP53 and PIK3CA (p<0.001). Hydrophobic mutations predicted for early relapse in patients with high nodal burden and <50% TILs tumors (training: HR 3.03, 95%CI 1.11–8.29, p = 0.031; validation: HR 2.90, 95%CI 0.97–8.70, p = 0.057), especially if compared to patients with >50% TILs tumors (training p = 0.003; validation p = 0.015).

Conclusions

TILs density is unrelated to mutation load in TNBC, which may be regarded as an unstable phenotype. If further validated, hydrophobic mutations along with TILs density may help identifying TNBC patients in higher risk for relapse.

Mechanisms of resistance and sensitivity to anti-HER2 therapies in HER2+ breast cancer

Breast Cancer (BC) is a highly prevalent disease. A woman living in the United States has a 12.3% lifetime risk of being diagnosed with breast cancer [1]. It is the most common female cancer and the second most common cause of cancer death in women [2]. Of note, amplification or overexpression of Human Epidermal Receptor 2 (HER2) oncogene is present in approximately 18 to 20% of primary invasive breast cancers, and until personalized therapy became available for this specific BC subtype, the worst rates of Overall Survival (OS) and Recurrence-Free Survival (RFS) were observed in the HER2+ BC cohort, compared to all other types, including triple negative BC (TNBC) [3].HER2 is a member of the epidermal growth factor receptor (EGFR) family. Other family members include EGFR or HER1, HER3 and HER4. HER2 can form heterodimers with any of the other three receptors, and is considered to be the preferred dimerization partner of the other HER or ErbB receptors [4]. Phosphorylation of tyrosine residues within the cytoplasmic domain is the result of receptor dimerization and culminates into initiation of a variety of signalling pathways involved in cellular proliferation, transcription, motility and apoptosis inhibition [5].In addition to being an important prognostic factor in women diagnosed with BC, HER2 overexpression also identifies those patients who benefit from treatment with agents that target HER2, such as trastuzumab, pertuzumab, trastuzumab emtansine (T-DM1) and small molecules tyrosine kinase inhibitors of HER2 [6, 11, 127].In fact, trastuzumab altered the natural history of patients diagnosed with HER2+ BC, both in early and metastatic disease setting, in a major way [8-10]. Nevertheless, there are many women that will eventually develop metastatic disease, despite being treated with anti-HER2 therapy in the early disease setting. Moreover, advanced tumors may reach a point where no anti-HER2 treatment will achieve disease control, including recently approved drugs, such as T-DM1.This review paper will concentrate on major biological pathways that ultimately lead to resistance to anti-HER2 therapies in BC, summarizing their mechanisms. Strategies to overcome this resistance, and the rationale involved in each tactics to revert this scenario will be presented to the reader.

Epigenetic changes in localized gastric cancer: the role of RUNX3 in tumor progression and the immune microenvironment

Gastric cancer (GC) pathogenesis involves genetic, epigenetic and environmental factors. Epigenetic alterations, such as DNA methylation are considered pivotal in the inactivation of tumor-related genes. We assessed a methylation panel of 5 genes to study their association to GC progression and microsatellite instability (MSI), and studied the role of RUNX3 in GC pathogenesis and the tumor immune microenvironment.The methylation status of 47 promoter-CpG islands was studied through MALDI-TOF mass spectrometry analysis in 35 Microsatellite stable (MSS) GC, 26 MSI, and 18 cancer-free samples (CFS), and 6 MSS GC and 4 MSI GC cell lines. We also studied RUNX3 expression by immunohistochemistry (IHC) in 40 samples, and validated differences in methylation levels between tumor, normal, and immune tissue in 14 additional samples.Unsupervised hierarchical clustering of methylation levels revealed no distinct subgroups between MSI and MSS samples or cell lines. CFSs clustered together showing higher levels of RUNX3 methylation compared to GC samples. RUNX3 showed protein silencing in cancer and normal mucosa, compared to inflammatory peritumoural infiltrate in almost all cases, showing a non-lymphocytic predominant pattern and being correlated with epigenetic silencing.Our results show aberrant promoter's methylation in APC, CDH1, CDKN2A, MLH1 and RUNX3 associated with GC, as well as a non-lymphocytic predominant infiltrate with high expression of RUNX3. Deep study of RUNX3 inflammation signaling could help in understanding inflammation and immune activation in the tumor microenvironment.

Immunotherapy in breast cancer: An overview of modern checkpoint blockade strategies and vaccines

Immune therapy has recently emerged as a standard-of-care strategy for the treatment of melanoma, lung cancer, bladder cancer, among other malignancies. However, the role of immune therapy in the treatment of breast cancer is still being determined. Two current strategies for harnessing the immune system to treat cancer include drugs that modulate key T cell inhibitory checkpoints and vaccines. Specifically, modern immune therapy strategies can facilitate T-cell mediated tumor regression by priming the immune system against specific tumor associated antigens, by modulating immunoregulatory signals, or both. In breast cancer, preliminary data from preclinical and early clinical studies are promising. In fact, clinical data with checkpoint blockade as monotherapy has been reported in multiple breast cancer subtypes to date, with durable responses observed in a significant proportion of women with chemotherapy resistant disease. However, because the number of genetic mutations and thus, the number of neoantigens available for immune response are modest in most breast cancers when compared with other cancers, most breast cancers may not be inherently sensitive to immune modulation and therefore may require strategies that enhance tumor associated antigen presentation if immune modulation strategies are to be effective. To that end, studies that combine checkpoint blockade with other strategies including established systemic therapies (including hormone therapy and chemotherapy), radiation therapy, and localized therapy including tumor freezing (cryoablation) are underway in breast cancer. Studies that combine checkpoint blockade with vaccines are also planned. Herein, we provide a brief summary of key components of the immune response against cancer, a rationale for the use of immune therapy in breast cancer, data from early clinical trials of checkpoint blockade and vaccine strategies in breast cancer, and future directions in the field.

Trastuzumab emtansine (T-DM1) renders HER2+ breast cancer highly susceptible to CTLA-4/PD-1 blockade

Targeted drug delivery with antibody-drug conjugates such as the HER2-directed ado-trastuzumab emtansine (T-DM1) has emerged as a powerful strategy for cancer therapy. We show that T-DM1 is particularly effective in eliciting antitumor immunity in patients with early breast cancer (WSG-ADAPT trial) and in a HER2-expressing orthotopic tumor model. In the latter, despite primary resistance to immunotherapy, combined treatment with T-DM1 and anti-CTLA-4/PD-1 (cytotoxic T lymphocyte-associated protein-4/programmed cell death protein-1) was curative because it triggered innate and adaptive immunity. Tumor rejection was accompanied by massive T cell infiltration, TH1 (T helper 1) cell polarization, and, notably, a substantial increase in regulatory T cells. Depletion of regulatory T cells resulted in inflammation and tissue damage, implying their essential role in protecting the host during therapy. This study provides insights into the mechanisms of T-DM1's therapeutic activity and a rationale for potential therapeutic combination strategies with immunotherapy.

The neutrophil lymphocyte ratio is associated with breast cancer prognosis: an updated systematic review and meta-analysis

Breast cancer (BC) is the most common female malignancy within the spectrum of human cancer. One promising way to reduce the mortality and morbidity of BC is to explore novel diagnostic markers for early diagnosis and prognostication. The neutrophil lymphocyte ratio (NLR) is a good reflection of inflammation, which plays an important role in tumor progression and metastasis. However, the association between NLR and BC prognosis remains unclear. The aim of this meta-analysis is to explore the prognostic value of NLR in BC. Among the screened references in the database, 12 eligible studies were identified in this study. Patients with a higher NLR had a shorter disease-free survival (hazard ratio =1.46, 95% confidence interval: 1.12-1.90, P=0.044) and overall survival (hazard ratio =2.03, 95% confidence interval: 1.41-2.93, P<0.001). In the subgroup analysis of NLR and disease-free survival, the studies from Eastern countries had a positive result with perfect homogeneity (I (2)=0); however, this homogeneity has not been achieved in studies from Western countries. In the subgroup analysis of the NLR and overall survival, the results of the univariate and multivariate analyses were completely different, with different heterogeneity. In the luminal A and luminal B subtypes, we found that there was no association between the NLR and overall survival in the BC patients. Positive results were obtained in the analyses of the human epidermal growth factor receptor 2 (HER2)-positive and triple-negative BC subtypes. In conclusion, this meta-analysis suggests that NLR is a good prognostic marker for BC, and patients with a higher NLR have poorer prognoses. Future studies should perform more detailed investigations to decrease heterogeneity and determine the appropriate cut-off values for different races.

MicroRNA-21 links epithelial-to-mesenchymal transition and inflammatory signals to confer resistance to neoadjuvant trastuzumab and chemotherapy in HER2-positive breast cancer patients

Patients with primary HER2-positive breast cancer benefit from HER2-targeted therapies. Nevertheless, a significant proportion of these patients die of disease progression due to mechanisms of drug resistance. MicroRNAs (miRNAs) are emerging as critical core regulators of drug resistance that act by modulating the epithelial- to-mesenchymal transition (EMT) and cancer-related immune responses. In this study, we investigated the association between the expression of a specific subset of 14 miRNAs involved in EMT processes and immune functions and the response to neoadjuvant trastuzumab and chemotherapy in 52 patients with HER2-overexpressing breast tumors. The expression of only a single miRNA, miR-21, was significantly associated with residual disease (p = 0.030) and increased after trastuzumab-chemotherapy (p = 0.012). A target prediction analysis coupled with in vitro and in vivo validations revealed that miR-21 levels inversely correlated with the expression of PTEN (rs = −0.502; p = 0.005) and PDCD4 (rs = −0.426; p = 0.019), which differentially influenced the drug sensitivity of HER2-positive breast cancer cells. However, PTEN expression was only marginally associated with residual disease. We further demonstrated that miR-21 was able to affect the response to both trastuzumab and chemotherapy, triggering an IL-6/STAT3/NF-κB-mediated signaling loop and activating the PI3K pathway. Our findings support the ability of miR-21 signaling to sustain EMT and shape the tumor immune microenvironment in HER2-positive breast cancer. Collectively, these data provide a rationale for using miR-21 expression as a biomarker to select trastuzumab-chemotherapy-resistant HER2-positive breast cancer patients who may benefit from treatments containing PI3K inhibitors or immunomodulatory drugs.

Biology and Management of Patients With Triple-Negative Breast Cancer

: Triple-negative breast cancer (TNBC) accounts for 15% of all breast cancers and is associated with poor long-term outcomes compared with other breast cancer subtypes. Because of the lack of approved targeted therapy, at present chemotherapy remains the mainstay of treatment for early and advanced disease. TNBC is enriched for germline BRCA mutation, providing a foundation for the use of this as a biomarker to identify patients suitable for treatment with DNA-damaging agents. Inherited and acquired defects in homologous recombination DNA repair, a phenotype termed "BRCAness," may be present in a large proportion of TNBC cases, making it an attractive selection and response biomarker for DNA-damaging therapy. Triple-negative breast cancer is a diverse entity for which additional subclassifications are needed. Increasing understanding of biologic heterogeneity of TNBC has provided insight into identifying potentially effective systemic therapies, including cytotoxic and targeted agents. Numerous experimental approaches are under way, and several encouraging drug classes, such as immune checkpoint inhibitors, poly(ADP-ribose) polymerase inhibitors, platinum agents, phosphatidylinositol-3-kinase pathway inhibitors, and androgen receptor inhibitors, are being investigated in TNBC. Molecular biomarker-based patient selection in early-phase trials has the potential to accelerate development of effective therapies for this aggressive breast cancer subtype. TNBC is a complex disease, and it is likely that several different targeted approaches will be needed to make meaningful strides in improving the outcomes.

IMPLICATIONS FOR PRACTICE

Triple-negative breast cancer (TNBC) is an aggressive subtype that is associated with poor outcomes. This article reviews clinical features and discusses the molecular diversity of this unique subtype. Current treatment paradigms, the role of germline testing, and platinum agents in TNBC are reviewed. Results and observations from pertinent clinical trials with potential implications for patient management are summarized. This article also discusses the clinical development and ongoing clinical trials of novel promising therapeutic agents in TNBC.

Concepts and targets in triple-negative breast cancer: recent results and clinical implications

Triple-negative breast cancer (TNBC) is a heterogeneous disease in which tumors are defined by lack of expression of the estrogen receptor (ER), the progesterone receptor (PR), and the human epidermal growth factor receptor 2 (HER2) receptor. No targeted therapies are available for the treatment of TNBC, and chemotherapy remains the standard of care. Gene expression profiling has identified six distinct molecular subtypes of TNBC. The identification of novel targets, coupled with the development of therapies for different subsets of TNBC, holds great promise for the future treatment of this aggressive form of breast cancer. This review focuses on novel therapies in development for the treatment of TNBC.

Deep Sequencing of T-cell Receptor DNA as a Biomarker of Clonally Expanded TILs in Breast Cancer after Immunotherapy

In early-stage breast cancer, the degree of tumor-infiltrating lymphocytes (TIL) predicts response to chemotherapy and overall survival. Combination immunotherapy with immune checkpoint antibody plus tumor cryoablation can induce lymphocytic infiltrates and improve survival in mice. We used T-cell receptor (TCR) DNA sequencing to evaluate both the effect of cryoimmunotherapy in humans and the feasibility of TCR sequencing in early-stage breast cancer. In a pilot clinical trial, 18 women with early-stage breast cancer were treated preoperatively with cryoablation, single-dose anti-CTLA-4 (ipilimumab), or cryoablation + ipilimumab. TCRs within serially collected peripheral blood and tumor tissue were sequenced. In baseline tumor tissues, T-cell density as measured by TCR sequencing correlated with TIL scores obtained by hematoxylin and eosin (H&E) staining. However, tumors with little or no lymphocytes by H&E contained up to 3.6 × 10⁶ TCR DNA sequences, highlighting the sensitivity of the ImmunoSEQ platform. In this dataset, ipilimumab increased intratumoral T-cell density over time, whereas cryoablation ± ipilimumab diversified and remodeled the intratumoral T-cell clonal repertoire. Compared with monotherapy, cryoablation plus ipilimumab was associated with numerically greater numbers of peripheral blood and intratumoral T-cell clones expanding robustly following therapy. In conclusion, TCR sequencing correlates with H&E lymphocyte scoring and provides additional information on clonal diversity. These findings support further study of the use of TCR sequencing as a biomarker for T-cell responses to therapy and for the study of cryoimmunotherapy in early-stage breast cancer. Cancer Immunol Res; 4(10); 835-44. ©2016 AACR.

A Pilot Study of Preoperative Single-Dose Ipilimumab and/or Cryoablation in Women with Early-Stage Breast Cancer with Comprehensive Immune Profiling

PURPOSE

To assess the safety and tolerability of preoperative cryoablation-mediated tumor antigen presentation and/or ipilimumab-mediated immune modulation in women with operable breast cancer.

EXPERIMENTAL DESIGN

In this pilot study, 19 women with breast cancer for whom mastectomy was planned were treated with preoperative tumor cryoablation (n = 7), single-dose ipilimumab at 10 mg/kg (n = 6), or both (n = 6). The primary outcome for this pilot study was safety/tolerability as defined as freedom from delays in pre-planned, curative-intent mastectomy. Exploratory studies of immune activation were performed on peripheral blood and tumor.

RESULTS

Preoperative cryoablation and/or ipilimumab were safe and tolerable, with no delays in pre-planned surgery. Grade III toxicity was seen in 1 of 19 (unrelated rash after ipilimumab). Combination therapy was associated with sustained peripheral elevations in: Th1-type cytokines, activated (ICOS⁺) and proliferating (Ki67⁺) CD4⁺ and CD8⁺ T cells, and posttreatment proliferative T-effector cells relative to T-regulatory cells within tumor.

CONCLUSIONS

Preoperative cryoablation and single-dose ipilimumab are safe alone or in combination with no surgical delays incurred. Potentially favorable intratumoral and systemic immunologic effects were observed with the combination, suggesting the possibility for induced and synergistic antitumor immunity with this strategy. Clin Cancer Res; 22(23); 5729-37. ©2016 AACR.

The 29.5 kb APOBEC3B Deletion Polymorphism Is Not Associated with Clinical Outcome of Breast Cancer

Increased APOBEC3B mRNA levels are associated with a hypermutator phenotype and poor prognosis in ER-positive breast cancer patients. In addition, a 29.5 kb deletion polymorphism of APOBEC3B, resulting in an APOBEC3A-B hybrid transcript, has been associated with an increased breast cancer risk and the hypermutator phenotype. Here we evaluated whether the APOBEC3B deletion polymorphism also associates with clinical outcome of breast cancer. Copy number analysis was performed by quantitative PCR (qPCR) in primary tumors of 1,756 Dutch breast cancer patients. The APOBEC3B deletion was found in 187 patients of whom 16 carried a two-copy deletion and 171 carried a one-copy deletion. The prognostic value of the APOBEC3B deletion for the natural course of the disease was evaluated among 1,076 lymph-node negative (LNN) patients who did not receive adjuvant systemic treatment. No association was found between APOBEC3B copy number values and the length of metastasis-free survival (MFS; hazard ratio (HR) = 1.00, 95% confidence interval (CI) = 0.90–1.11, P = 0.96). Subgroup analysis by ER status also did not reveal an association between APOBEC3B copy number values and the length of MFS. The predictive value of the APOBEC3B deletion was assessed among 329 ER-positive breast cancer patients who received tamoxifen as the first-line therapy for recurrent disease and 226 breast cancer patients who received first-line chemotherapy for recurrent disease. No association between APOBEC3B copy number values and the overall response rate (ORR) to either tamoxifen (odds ratio (OR) = 0.88, 95% CI = 0.69–1.13, P = 0.31) or chemotherapy (OR = 0.97, 95% CI = 0.71–1.33, P = 0.87) was found. Thus, in contrast to APOBEC3B mRNA levels, the APOBEC3B deletion polymorphism has neither a prognostic nor a predictive value for breast cancer patients. Although a correlation exists between APOBEC3B copy number and mRNA expression, it is relatively weak. This suggests that other mechanisms exist that may affect and therefore determine the prognostic value of APOBEC3B mRNA levels.

A bad tumor biomarker is as bad as a bad drug: The gap between genomics data and phenotype to predict response

The search for novel prognostic and predictive parameters in breast carcinoma is relentless. The new technological advances in gene expression profiling and in mutational analysis will hopefully prove to be clinically useful in informing the choice for the systemic therapy. For the time being, we are still relying in established immunohistochemical markers, namely estrogen and progesterone receptors, HER2 and Ki67. Advances in the harmonization of pre-analytical, analytical and interpretative variables may improve accuracy and reproducibility of the results.

CCR 20th Anniversary Commentary: Gene-Expression Signature in Breast Cancer--Where Did It Start and Where Are We Now?

Desmedt and colleagues published two articles, one in the June 1, 2007 issue, and the other in the August 15, 2008, issue of Clinical Cancer Research, that showed gene-expression signatures to be proliferation driven and time dependent, with their prognostic power decreasing with increasing follow-up years. Moreover, the articles showed that immune response is a crucial determinant of prognosis in the HER2-positive and estrogen receptor-negative/HER2-negative subtypes, providing a rationale to further explore the role of the antitumor immune response in these breast cancer subtypes.

Pretreatment Prognostic Nutritional Index Is an Independent Predictor of Survival in Patients With Metastatic Renal Cell Carcinoma Treated With Targeted Therapy

BACKGROUND

In the present study we examined the effect of the Prognostic Nutritional Index (PNI) on the overall survival (OS) and progression-free survival (PFS) of patients with metastatic renal cell carcinoma (RCC) treated with targeted therapy.

PATIENTS AND METHODS

The study included 125 patients with metastatic RCC. Pretreatment PNI was calculated as 10 × serum albumin (g/dL) + 0.005 × total lymphocyte count (per mm³). Univariable and multivariable Cox proportional hazards models were used to assess the correlation between pretreatment PNI and OS and PFS. Harrell concordance index was used to measure discrimination.

RESULTS

The median follow-up time was 45.3 months (interquartile range, 23.7-77.3 months). Decreased PNI was significantly associated with older female patients, poor Eastern Cooperative Oncology Group performance status, types of initial drug, and increased Memorial Sloan Kettering Cancer Center (MSKCC) and Heng risk score (P < .05). An increase in the PNI of 1 unit was associated with a 10% decrease in the risk of death from RCC (hazard ratio, 0.90; P < .001). In the multivariable analysis, the PNI was an independent prognostic factor for OS (P < .001). In intermediate-risk patients according to MSKCC and Heng risk criteria, OS was better in the high PNI group than in the low PNI group (P = .0136 and P = .0009, respectively).

CONCLUSION

PNI is an independent prognostic factor in patients with metastatic RCC treated with targeted therapy. When used as an adjunct, it increases the prognostic accuracy of established factors and could be a valuable tool for tailoring surveillance, patient counseling, and clinical trial design.

Whole-transcriptome analysis links trastuzumab sensitivity of breast tumors to both HER2 dependence and immune cell infiltration

While results thus far demonstrate the clinical benefit of trastuzumab, some patients do not respond to this therapy. To identify a molecular predictor of trastuzumab benefit, we conducted whole-transcriptome analysis of primary HER2+ breast carcinomas obtained from patients treated with trastuzumab-containing therapies and correlated the molecular portrait with treatment benefit.

The estimated association between gene expression and relapse-free survival allowed development of a trastuzumab risk model (TRAR), with ERBB2 and ESR1 expression as core elements, able to identify patients with high and low risk of relapse. Application of the TRAR model to 24 HER2+ core biopsies from patients treated with neo-adjuvant trastuzumab indicated that it is predictive of trastuzumab response. Examination of TRAR in available whole-transcriptome datasets indicated that this model stratifies patients according to response to trastuzumab-based neo-adjuvant treatment but not to chemotherapy alone. Pathway analysis revealed that TRAR-low tumors expressed genes of the immune response, with higher numbers of CD8-positive cells detected immunohistochemically compared to TRAR-high tumors.

The TRAR model identifies tumors that benefit from trastuzumab-based treatment as those most enriched in CD8-positive immune infiltrating cells and with high ERBB2 and low ESR1 mRNA levels, indicating the requirement for both features in achieving trastuzumab response.

CCR 20th Anniversary Commentary: Simpson's Paradox and Neoadjuvant Trials

The research article by Carey and colleagues, published in the April 15, 2007, issue of Clinical Cancer Research, described the relationship between response to neoadjuvant chemotherapy and outcome by tumor subtype. Today neoadjuvant clinical trials are often designed to provide correlative data to help identify predictive biomarkers or to focus on poor-risk patients identified by residual disease after neoadjuvant treatment.

Integrative proteomic and gene expression analysis identify potential biomarkers for adjuvant trastuzumab resistance: analysis from the Fin-her phase III randomized trial

Trastuzumab is a remarkably effective therapy for patients with human epidermal growth factor receptor 2 (HER2) - positive breast cancer (BC). However, not all women with high levels of HER2 benefit from trastuzumab.

By integrating mRNA and protein expression data from Reverse-Phase Protein Array Analysis (RPPA) in HER2-positive BC, we developed gene expression metagenes that reflect pathway activation levels. Next we assessed the ability of these metagenes to predict resistance to adjuvant trastuzumab using gene expression data from two independent datasets.

10 metagenes passed external validation (false discovery rate [fdr] < 0.05) and showed biological relevance with their pathway of origin. These metagenes were further screened for their association with trastuzumab resistance. An association with trastuzumab resistance was observed and validated only for the AnnexinA1 metagene (ANXA1). In the randomised phase III Fin-her study, tumours with low levels of the ANXA1 metagene showed a benefit from trastuzumab (multivariate: hazard ratio [HR] for distant recurrence = 0.16[95%CI 0.05–0.5]; p = 0.002; fdr = 0.03), while high expression levels of the ANXA1 metagene were associated with a lack of benefit to trastuzmab (HR = 1.29[95%CI 0.55–3.02]; p = 0.56). The association of ANXA1 with trastuzumab resistance was successfully validated in an independent series of subjects who had received trastuzumab with chemotherapy (Log Rank; p = 0.01).

In conclusion, in HER2-positive BC, some proteins are associated with distinct gene expression profiles. Our findings identify the ANXA1metagene as a novel biomarker for trastuzumab resistance.

Spatial Heterogeneity in the Tumor Microenvironment

Recent developments in studies of tumor heterogeneity have provoked new thoughts on cancer management. There is a desperate need to understand influence of the tumor microenvironment on cancer development and evolution. Applying principles and quantitative methods from ecology can suggest novel solutions to fulfil this need. We discuss spatial heterogeneity as a fundamental biological feature of the microenvironment, which has been largely ignored. Histological samples can provide spatial context of diverse cell types coexisting within the microenvironment. Advanced computer-vision techniques have been developed for spatial mapping of cells in histological samples. This has enabled the applications of experimental and analytical tools from ecology to cancer research, generating system-level knowledge of microenvironmental spatial heterogeneity. We focus on studies of immune infiltrate and tumor resource distribution, and highlight statistical approaches for addressing the emerging challenges based on these new approaches.

Differential tumor infiltration by T-cells characterizes intrinsic molecular subtypes in breast cancer

Background

Molecular subtypes of breast cancer and presence of tumor-infiltrating immune cells have both been implicated as important predictive and prognostic factors for improved risk stratification and treatment individualization of breast cancer patients. Their association, however, has not been studied in detail. The aim of this study was to evaluate the expression of the T cell markers CD8, FoxP3, CD3 and ζ-chain in molecular subtypes of the invasive margin and tumor center of breast cancer and corresponding sentinel nodes and to deduct prognostic information from these findings.

Methods

Tumor and sentinel node sections from 177 patients with primary, invasive, unilateral early-stage breast cancer were stained by immunohistochemistry and T-cell phenotypes quantified manually. Clinical data were collected from medical records.

Results

The degree of T-cell infiltration and expression of all markers differed significantly among the molecular subtypes, being highest in non-luminal, more aggressive tumors: more T-cell infiltration and higher expression of all markers were associated with hormone receptor negativity, higher proliferation and higher histological grades, but also with larger tumor size. Basal-like tumors, and most remarkably their tumor centers, hosted the highest number of FoxP3+ T-cells with an unfavorable ratio to cytotoxic CD8+ T-cells. T-cell infiltration was generally higher in the invasive margin than the tumor center. A scoring system based on densities of CD3 and CD8 could significantly separate molecular subtypes (p < 0.001).

Conclusions

Thus, immunological patterns with functional implications within each subtype are associated with prognostic factors. These findings should be further validated in studies using larger patient populations and longer follow-up.

Electronic supplementary material

The online version of this article (doi:10.1186/s12967-016-0983-9) contains supplementary material, which is available to authorized users.

Immune DNA signature of T-cell infiltration in breast tumor exomes

Tumor infiltrating lymphocytes (TILs) have been associated with favorable prognosis in multiple tumor types. The Cancer Genome Atlas (TCGA) represents the largest collection of cancer molecular data, but lacks detailed information about the immune environment. Here, we show that exome reads mapping to the complementarity-determining-region 3 (CDR3) of mature T-cell receptor beta (TCRB) can be used as an immune DNA (iDNA) signature. Specifically, we propose a method to identify CDR3 reads in a breast tumor exome and validate it using deep TCRB sequencing. In 1,078 TCGA breast cancer exomes, the fraction of CDR3 reads was associated with TILs fraction, tumor purity, adaptive immunity gene expression signatures and improved survival in Her2+ patients. Only 2/839 TCRB clonotypes were shared between patients and none associated with a specific HLA allele or somatic driver mutations. The iDNA biomarker enriches the comprehensive dataset collected through TCGA, revealing associations with other molecular features and clinical outcomes.

A prognostic index for locoregional recurrence after neoadjuvant chemotherapy

Background

The appropriate selection criteria for breast-conserving surgery (BCS) or mastectomy after neoadjuvant chemotherapy (NAC) are poorly defined. The aim of this study is to analyse the incidence and prognostic factors for locoregional recurrence (LRR) in patients with breast cancer (BC) treated with NAC to develop a prognostic score to help with clinical decision-making.

Materials and methods

Using our retrospective maintained BC database, we identified 730 patients treated with NAC (327 patients treated with BCS and 403 patients treated with mastectomy) between 1998 and 2014. To identify variables associated with an increased LRR rate, we performed firstly Kaplan–Meier curves, with comparisons among groups using log-rank test, and then, significant variables were included in a multivariate analysis using Cox proportional hazards. The prognostic index was developed by assigning score 0 (favourable) or score 1 (unfavourable) for each significant variable of multivariate analysis and was created separately for patients with BCS and mastectomy.

Results

At a median follow-up of 72 months, the 6-year cumulative incidence of LRR was 7.2% ( ± 3%) for BCS and 7.9% ( ± 3%) for mastectomy.

By univariate analysis, variables associated with an increased LRR were for BCS: HER2 positive, grade III, ductal carcinoma in situ (DCIS), No-pCR (ypTis, ypN0), and age < 40 years; and for mastectomy, HER2-positive, DCIS, No-pCR, and LVI. By multivariate analysis, variables associated with an increased LRR were for BCS: HER2 positive (HR: 11.1, p = 0.001), DCIS (HR: 3.1, p = 0.005), and age < 40 years (HR: 2.8, p = 0.02); and for mastectomy: HER2 positive (HR: 9.5, p = 0.03), DCIS (HR: 2.7, p = 0.01), No-pCR (HR: 11.4, p = 0.01), and age < 40 years (HR: 2.8, p = 0.006).

The score stratified patients into three subsets with statistically different levels of risk for LRR. For BCS, the six-year LRR rates were 3%, 13%, and 33% for the low (score 0, n = 120), intermediate (score 1, n = 95) and high (score 2–3, n = 27) risk groups, respectively (p = 0.001). For mastectomy, the six-year LRR rates were 0%, 8%, and 27% for the low (score 0, n = 20), intermediate (score 1–2, n 191), and high (score 3–4, n = 30) risk groups, respectively (p = 0.001). Of note, 21 patients that had a LRR event were HER2 positive, all of them had received trastuzumab.

Conclusions

Patients with a score of 0, which made up to 19% of the study population, had very low risk of LRR. The score enabled the identification of a small group (7%) of patients with very high risk of LRR, and who may benefit from alternative treatment.

The molecular landscape of high-risk early breast cancer: comprehensive biomarker analysis of a phase III adjuvant population

Breast cancer is a heterogeneous disease and patients are managed clinically based on ER, PR, HER2 expression, and key risk factors. We sought to characterize the molecular landscape of high-risk breast cancer patients enrolled onto an adjuvant chemotherapy study to understand how disease subsets and tumor immune status impact survival. DNA and RNA were extracted from 861 breast cancer samples from patients enrolled onto the United States Oncology trial 01062. Samples were characterized using multiplex gene expression, copy number, and qPCR mutation assays. HR⁺ patients with a PIK3CA mutant tumor had a favorable disease-free survival (DFS; HR 0.66, P=0.05), however, the prognostic effect was specific to luminal A patients (Luminal A: HR 0.67, P=0.1; Luminal B: HR 1.01, P=0.98). Molecular subtyping of triple-negative breast cancers (TNBCs) suggested that the mesenchymal subtype had the worst DFS, whereas the immunomodulatory subtype had the best DFS. Profiling of immunologic genes revealed that TNBC tumors (n=280) displaying an activated T-cell signature had a longer DFS following adjuvant chemotherapy (HR 0.59, P=0.04), while a distinct set of immune genes was associated with DFS in HR⁺ cancers. Utilizing a discovery approach, we identified genes associated with a high risk of recurrence in HR⁺ patients, which were validated in an independent data set. Molecular classification based on PAM50 and TNBC subtyping stratified clinical high-risk patients into distinct prognostic subsets. Patients with high expression of immune-related genes showed superior DFS in both HR⁺ and TNBC. These results may inform patient management and drug development in early breast cancer.

Strategies to modulate the immune system in breast cancer: checkpoint inhibitors and beyond

Is breast cancer (BC) immunogenic? Many data suggest that it is. Many observations demonstrated the prognostic role of tumor-infiltrating lymphocytes (TILs) in triple negative (TN) and human epidermal growth factor receptor 2 (HER-2)-positive BC. TNBCs are poorly differentiated tumors with high genetic instability and very high heterogeneity. This heterogeneity enhances the 'danger signals' and select clone variants that could be more antigenic or, in other words, that could more strongly stimulate a host immune antitumor response. The response to chemotherapy is at least partly dependent on an immunological reaction against those tumor cells that are dying during the chemotherapy. One of the mechanisms whereby chemotherapy can stimulate the immune system to recognize and destroy malignant cells is commonly known as immunogenic cell death (ICD). ICD elicits an adaptive immune response. Which are the clinical implications of all 'immunome' data produced in the last years? First, validate prognostic or predictive role of TILs. Second, validate immune genomic signatures that may be predictive and prognostic in patients with TN disease. Third, incorporate an 'immunoscore' into traditional classification of BC, thus providing an essential prognostic and potentially predictive tool in the pathology report. Fourth, implement clinical trials for BC in the metastatic setting with drugs that target immune-cell-intrinsic checkpoints. Blockade of one of these checkpoints, cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) or the programmed cell death 1 (PD-1) receptor may provide proof of concepts for the activity of an immune-modulation approach in the treatment of a BC.

Prognostic and predictive immune gene signatures in breast cancer

PURPOSE OF REVIEW

Here, we focus on molecular biomarkers derived from transcriptomic studies to summarize the recent advances in our understanding of the mechanisms associated with differential prognosis and treatment outcome in breast cancer.

RECENT FINDINGS

Breast cancer is certainly immunogenic; yet it has been historically resistant to immunotherapy. In the past few years, refined immunotherapeutic manipulations have been shown to be effective in a significant proportion of cancer patients. For example, drugs targeting the PD-1 immune checkpoint have been proven to be an effective therapeutic approach in several solid tumors including melanoma and lung cancer. Very recently, the activity of such therapeutics has also been demonstrated in breast cancer patients. Pari passu with the development of novel immune modulators, the transcriptomic analysis of human tumors unveiled unexpected and paradoxical relationships between cancer cells and immune cells.

SUMMARY

This review examines our understanding of the molecular pathways associated with intratumoral immune response, which represents a critical step for the implementation of stratification strategies toward the development of personalized immunotherapy of breast cancer.

Tumor-infiltrating lymphocytes (TILs) are a powerful prognostic marker in patients with triple-negative breast cancer enrolled in the IBCSG phase III randomized clinical trial 22-00

The purpose of this study was to assess the prognostic and predictive value of tumor-infiltrating lymphocytes (TILs) in the triple-negative breast cancer (TNBC) cohort of the phase III IBCSG trial 22-00, comparing low-dose oral 'metronomic' cyclophosphamide-methotrexate maintenance chemotherapy (CM-maintenance) to no-CM-maintenance in early breast cancer. TILs were evaluated in full-face hematoxylin-and-eosin-stained sections of tumor samples confirmed centrally as TNBC (< 1 % of ER and PgR immunoreactivity and absence of HER2 overexpression or amplification). Mononuclear cells were evaluated in the stromal area within the borders of the invasive tumor. The primary endpoint was breast cancer-free interval (BCFI). Cox proportional hazards regression model assessed the association of BCFI and secondary endpoints with TILs score. In the 647 tumor samples, the median percentage of TILs was 18 % (IQR = 8-40 %), with 18 % having TILs ≥ 50 % (lymphocyte-predominant breast cancer, LPBC). At a median follow-up of 6.9 years, TILs were associated with better prognosis. For every 10 % increase of TILs, BCFI risk reduction was 13 % (HR 0.87, 95 % CI 0.79-0.95,P = 0.003). DFS, DRFI, and OS risk reductions were 11 % (P = 0.005), 16 % (P = 0.003), and 17 % (P < 0.001), respectively. Multivariable analysis confirmed the independent prognostic value of TILs. No significant TILs-by-treatment interaction was observed (P = 0.39) for associations of TILs with BCFI, although patients with LPBC receiving CM-maintenance had a greater breast cancer risk reduction (HR 0.64,95 % CI 0.23-1.78) than those with non-LPBC (TILs < 50 %) (HR 0.96, 95 % CI 0.67-1.40). TILs score is a potent prognostic factor in patients with TNBC. Low-dose chemotherapy confers a greater (not statistically significant) clinical benefit in patients with LPBC.

Effects of TP53 and PIK3CA mutations in early breast cancer: a matter of co-mutation and tumor-infiltrating lymphocytes

The purpose of this study is to investigate whether the outcome of breast cancer (BC) patients treated with adjuvant chemotherapy is affected by co-mutated TP53 and PIK3CA according to stromal tumor-infiltrating lymphocytes (TILs). Paraffin tumors of all clinical subtypes from 1661 patients with operable breast cancer who were treated within 4 adjuvant trials with anthracycline-taxanes chemotherapy were informative for TP53 and PIK3CA mutation status (semiconductor sequencing genotyping) and for stromal TILs density. Disease-free survival (DFS) was examined. TP53 mutations were associated with higher (p < 0.001) and PIK3CA with lower (p = 0.004) TILs in an ER /PgR-specific manner (p < 0.001). Mutations did not affect the favorable DFS of patients with lymphocyte-predominant (LP) BC. Within non-LPBC, PIK3CA-only mutations conferred best, while TP53-PIK3CA co-mutations (6 % of all tumors) conferred worst DFS (HR 0.59; 95 % CI 0.44-0.79; p = 0.001 for PIK3CA-only). TP53-only mutations were unfavorable in patients with lower TILs, while patients with lower TILs performed worse if their tumors carried TP53-only mutations (interaction p = 0.046). Multivariate analysis revealed favorable PIK3CA-only mutations in non-LPBC (HR 0.64; 95 % CI 0.47-0.88; p = 0.007), and unfavorable TP53 mutations in ER/PgRpos/HER2neg (HR 1.55; 95 % CI 1.07-2.24; p = 0.021). Mutations did not interact with TILs in non-LP triple-negative and HER2-positive patients. TP53 and PIK3CA mutations appear to have diverse effects on the outcome of early BC patients, according to whether these genes are co-mutated or not, and for TP53 according to TILs density and ER/PgR-status. These findings need to be considered when evaluating the effect of these two most frequently mutated genes in the context of large clinical trials.

Towards tumor immunodiagnostics

Immunodiagnostic markers applicable on tissue or cytologic material may be prognostic or predictive of response to immunomodulatory drugs and may also be classified according to whether they are cell-specific or tumor-tissue-specific. Cell-specific markers are evaluated under the microscope as (I) morphological, corresponding to the assessment of tumor infiltrating immune cells on routine hematoxylin & eosin (H&E) sections; and (II) immunophenotypic, including the immunohistochemical (IHC) assessment of markers characteristic for tumor infiltrating immune cells. Tumor-tissue-specific markers are assessed in tissue extracts that may be enriched in neoplastic cells but almost inevitably also contain stromal and immune cells infiltrating the tumor. Such markers include (I) immune-response-related gene expression profiles, and (II) tumor genotype characteristics, as recently assessed with large-scale genotyping methods, usually next generation sequencing (NGS) applications. Herein, we discuss the biological nature of immunodiagnostic markers, their potential clinical relevance and the shortcomings that have, as yet, prevented their clinical application.

Immune Signatures Following Single Dose Trastuzumab Predict Pathologic Response to PreoperativeTrastuzumab and Chemotherapy in HER2-Positive Early Breast Cancer

PURPOSE

Recent data suggest that intrinsic subtype and immune cell infiltration may predict response to trastuzumab-based therapy. We studied the interaction between these factors, changes in immune signatures following brief exposure to trastuzumab, and achievement of pathologic complete response (pCR) to subsequent preoperative trastuzumab and chemotherapy in HER2-positive breast cancer.

EXPERIMENTAL DESIGN

In patients enrolled on two multicenter trials (03-311 and 211B), tumor core biopsies were obtained at baseline and after brief exposure to single-agent trastuzumab or nab-paclitaxel. Gene expression profiles were assessed to assign PAM50 subtypes, measure immune cell activation, and were correlated with response.

RESULTS

The pCR rate was significantly higher in HER2-enriched tumors in the Discovery, 03-311 (36%, P = 0.043) dataset, as compared with other subtypes, which validated in 211B (50%, P = 0.048). Significant increases in a signature of immune cell admixture (Immune Index) were observed only following brief exposure to trastuzumab in HER2-enriched tumors (Discovery/03-311, P = 0.05; Validation/211B, P = 0.02). Increased Immune Index was predictive of response after brief exposure (03-311, P = 0.03; 211B, P = 0.04), but not at baseline, in addition to increased expression of a CD4(+) follicular helper T-cell signature (03-311, P = 0.05; 211B, P = 0.04). Brief exposure to trastuzumab significantly increased gene expression of the T-cell marker PD-1 in HER2-enriched tumors (Discovery/03-311, P = 0.045) and PD-1 positivity by IHC (Validation/211B, P = 0.035).

CONCLUSIONS

Correlations between pCR rates, increases in Immune Index and markers of T-cell activity following brief exposure to trastuzumab in HER2-enriched tumors provide novel insights into the interaction between tumor biology, antitumor immunity, and response to treatment, and suggest potential clinically useful biomarkers in HER2(+) breast cancers. Clin Cancer Res; 22(13); 3249-59. ©2016 AACR.

Prognostic and predictive impacts of tumor-infiltrating lymphocytes differ between Triple-negative and HER2-positive breast cancers treated with standard systemic therapies

Tumor-infiltrating lymphocytes (TILs) have potential value for stratifying the treatment of breast cancer (BC), though their precise use remains unclear. We aimed to investigate the utility of TILs using an alternative approach in different settings. We reviewed patients with triple-negative (TN) or human epithelial growth factor receptor 2 (HER2)-positive invasive ductal carcinomas from a single institutional cohort and classified archived hematoxylin–eosin-stained samples in terms of TIL score as low (<10 %), intermediate, and high (>50 %). The prognostic and predictive values of TILs were analyzed retrospectively in both adjuvant and neo-adjuvant settings. In the adjuvant setting, the presence of TILs at primary surgery was a significant favorable prognostic factor among 154 TNBCs [relapse-free survival (RFS): p = 0.015], but not among 183 HER2+ BCs (RFS: p = 0.097). The TNBC low-TIL group tended to relapse earlier. In the neo-adjuvant setting, detection of TILs on biopsy before primary systemic therapy was associated with the ratio of patients achieving pathological complete response among 48 TNBCs (p = 0.024), but not among 58 HER2+ BCs (p = 0.30). The presence of TILs in surgical specimens after systemic therapy had prognostic value in HER2+ BC (RFS: p = 0.007). The impact of TILs differs between patients with TN and HER2+ BC treated with standard therapies. Our three-grade scale for TILs may contribute to our understanding of the importance of the tumor microenvironment in routine practice. TILs after primary systemic therapy may be useful for the further stratification of treatment of HER2+ BC.

Circulating Tumor Cells (CTC) Are Associated with Defects in Adaptive Immunity in Patients with Inflammatory Breast Cancer

Background: Circulating tumor cells (CTCs) play a crucial role in tumor dissemination and are prognostic in primary and metastatic breast cancer. Peripheral blood (PB) immune cells contribute to an unfavorable microenvironment for CTC survival. This study aimed to correlate CTCs with the PB T-cell immunophenotypes and functions of patients with inflammatory breast cancer (IBC).

Methods: This study included 65 IBC patients treated at the MD Anderson Cancer Center. PB was obtained from patients prior to starting a new line of chemotherapy for CTCs enumeration by CellSearch^®, and T cell phenotype and function by flow cytometry; the results were correlated with CTCs and clinical outcome.

Results: At least 1 CTC (≥1) or ≥5 CTCs was detected in 61.5% or 32.3% of patients, respectively. CTC count did not correlate with total lymphocytes; however, patients with ≥1 CTC or ≥5 CTCs had lower percentages (%) of CD3+ and CD4+ T cells compared with patients with no CTCs or <5 CTCs, respectively. Patients with ≥1 CTC had a lower percentage of T-cell receptor (TCR)-activated CD8+ T cells synthesizing TNF-α and IFN-γ and a higher percentage of T-regulatory lymphocytes compared to patients without CTCs. In multivariate analysis, tumor grade and % CD3+ T-cells were associated with ≥1 CTC, whereas ≥5 CTC was associated with tumor grade, stage, % CD3+ and % CD4+ T cells, and % TCR-activated CD8 T-cells synthesizing IL-17.

Conclusions: IBC patients with CTCs in PB had abnormalities in adaptive immunity that could potentially impact tumor cell dissemination and initiation of the metastatic cascade.

Tumour infiltrating lymphocytes correlate with improved survival in patients with oesophageal adenocarcinoma

BACKGROUND

Oesophageal adenocarcinoma (OAC) is increasingly common in the west, and survival remains poor at 10-15 % at 5 years. Immune responses are increasingly implicated as a determining factor of tumour progression. The ability of lymphocytes to recognise tumour antigens provides a mechanism for a host immune attack against cancer providing a potential treatment strategy.

MATERIALS AND METHODS

Tumour infiltrating lymphocytes (TILs: CD3+, CD4+, CD8+ and FOXp3+) were assessed by immunohistochemistry using tissue microarrays in a contemporary and homogeneous cohort of OAC patients (n = 128) undergoing curative treatment.

RESULTS

Multivariate analysis identified three independent prognostic factors for improved cancer-specific survival (CSS): increased CD8+ TILs (p = 0.003), completeness of resection (p < 0.0001) and lower pathological N stage (p < 0.0001). Independent prognostic factors for favourable disease-free survival included surgery-only treatment (p = 0.015), completeness of resection (p = 0.001), increased CD8+ TILs (p < 0.0001) and reduced pathological N stage (p < 0.0001). Higher levels of TILs in the pathological specimen were associated with significant pathological response to neoadjuvant chemotherapy (NAC). On multivariate analysis increased levels of CD4+ (p = 0.017) and CD8+ TILs (p = 0.005) were associated with significant local tumour regression and lymph node downstaging, respectively.

DISCUSSION

Our results establish an association of TILs and survival in OAC, as seen in other solid tumours, and identify particular TIL subsets that are present at higher levels in patients who responded to NAC compared to non-responders. These findings highlight potential therapeutic strategies in EAC based on utilising the host immunological response and highlight the immune responses biomarker potential.

Predictive biomarkers in the treatment of HER2-positive breast cancer: an ongoing challenge

The transmembrane tyrosine kinase receptor HER2 is overexpressed in 20% of invasive breast cancers and is associated with more aggressive disease. Until the advent of targeted agents, HER2 was associated with worse outcome. Trastuzumab, a recombinant humanized anti-HER2 monoclonal antibody, combined with chemotherapy improves disease-free and overall survival in both primary and metastatic tumors and represents a foundation of care for patients with HER2-positive breast cancers. However, a sizeable number of patients do not respond to this reagent, indicating the need for a biomarker able to recognize resistant tumors. Here, we review various studies on mechanisms of action and resistance to trastuzumab that have proven relevant in understanding how tumor care can be tailored to all HER2-positive patients.

Triple-negative breast cancer: treatment challenges and solutions

Triple-negative breast cancers (TNBCs) are defined by the absence of estrogen and progesterone receptors and the absence of HER2 overexpression. These cancers represent a heterogeneous breast cancer subtype with a poor prognosis. Few systemic treatment options exist besides the use of chemotherapy (CT). The heterogeneity of the disease has limited the successful development of targeted therapy in unselected patient populations. Currently, there are no approved targeted therapies for TNBC. However, intense research is ongoing to identify specific targets and develop additional and better systemic treatment options. Standard adjuvant and neoadjuvant regimens include anthracyclines, cyclophosphamide, and taxanes. Platinum-based CT has been proposed as another CT option of interest in TNBC. We review the role of this therapy in general, and particularly in patients carrying BRCA germ-line mutations. Available data concerning the role of platinum-based CT in TNBC were acquired primarily in the neoadjuvant setting. The routine use of platinum-based CT is not yet recommended by available guidelines. Many studies have reported the molecular characterization of TNBCs. Several actionable targets have been identified. Novel therapeutic strategies are currently being tested in clinical trials based on promising results observed in preclinical studies. These targets include androgen receptor, EGFR, PARP, FGFR, and the angiogenic pathway. We review the recent data on experimental drugs in this field. We also discuss the recent data concerning immunologic checkpoint inhibitors.

Triple-negative breast cancer: challenges and opportunities of a heterogeneous disease

Chemotherapy is the primary established systemic treatment for patients with triple-negative breast cancer (TNBC) in both the early and advanced-stages of the disease. The lack of targeted therapies and the poor prognosis of patients with TNBC have fostered a major effort to discover actionable molecular targets to treat patients with these tumours. Massively parallel sequencing and other 'omics' technologies have revealed an unexpected level of heterogeneity of TNBCs and have led to the identification of potentially actionable molecular features in some TNBCs, such as germline BRCA1/2 mutations or 'BRCAness', the presence of the androgen receptor, and several rare genomic alterations. Whether these alterations are molecular 'drivers', however, has not been clearly established. A subgroup of TNBCs shows a high degree of tumour-infiltrating lymphocytes that also correlates with a lower risk of disease relapse and a higher likelihood of benefit from chemotherapy. Proof-of-principle studies with immune-checkpoint inhibitors in advanced-stage TNBC have yielded promising results, indicating the potential benefit of immunotherapy for patients with TNBC. In this Review, we discuss the most relevant molecular findings in TNBC from the past decade and the most promising therapeutic opportunities derived from these data.

No effect of tumor-infiltrating lymphocytes (TILs) on prognosis in patients with early triple-negative breast cancer: Validation of recommendations by the International TILs Working Group 2014

PURPOSE

The aim of this study was to examine the International TILs Working Group 2014 (IWG) recommendations for evaluating the clinical utility of tumor-infiltrating lymphocytes (TILs) in patients with early triple-negative breast cancer (TNBC).

METHODS

Records for 133 patients with early TNBC who underwent surgery between 2008 and 2010 were reviewed. A total of 121 of 133 formalin-fixed, paraffin-embedded tumor samples were available and reviewed following IWG recommendations.

RESULTS

Most of the patients had node-negative T1-2 tumors and received adjuvant chemotherapy; T1-2 tumors accounted for 117 of 121 cases. Sixty-two percent (75/121) of all patients had >10% stromal TILs. Intratumoral TILs and lymphocyte-predominant breast cancer (LPBC) were observed in 72% and 19% of the patients, respectively. However, there were no significant differences according to the presence of stromal TILs, intratumoral TILs, TILs at the invasive edge, or LPBC in terms of recurrence-free and overall survival (all P > 0.05). A multivariate analysis adjusted for T and N stage, grade, and adjuvant chemotherapy revealed that no TILs parameters were associated with survival outcomes.

CONCLUSIONS

TILs evaluations following the IWG recommendations may not be useful for predicting survival outcomes in patients with early TNBC. J. Surg. Oncol. 2016;114:17-21. © 2016 Wiley Periodicals, Inc.

Immune infiltrates in the breast cancer microenvironment: detection, characterization and clinical implication

Although unlike melanoma, breast cancer is not generally viewed as a highly immunogenic cancer, recent studies have described a rich tumor immune microenvironment in a subset of breast cancers. These immune infiltrates, comprised cells from the innate and adaptive immune response, can be detected and characterized in biopsy specimens and have prognostic value. Tumor-infiltrating lymphocytes (TILs) represent the majority of mononuclear immune infiltrates in the breast tumor microenvironment and can be easily identified in formalin-fixed paraffin-embedded tissues after standard hematoxylin and eosin staining. High levels of TILs are most common in HER2+ and basal-like subtypes where they are associated with good prognosis and with response to certain therapies such as the anti-HER2 antibody trastuzumab. International collaborative efforts are underway to standardize the assessment of TILs so as to facilitate their implementation as a breast cancer biomarker. Using immunohistochemistry to further characterize TILs, recent reports describe the presence of important lymphocyte populations including CD8+ cytotoxic, FOXP3+ regulatory, and CD4+ helper and follicular T cells which have overlapping associations with prognosis and response to therapies. Moreover, recently identified immune checkpoint markers (PD-1, PD-L1) are present in some breast cancers, implying some cases might be especially amenable to immune checkpoint inhibitor treatment strategies which are being evaluated in a number of active clinical trials.