Immune Cell Abundance and T-cell Receptor Landscapes Suggest New Patient Stratification Strategies in Head and Neck Squamous Cell Carcinoma.

Head and neck squamous cell carcinoma (HNSCC) is a molecularly and spatially heterogeneous disease frequently characterized by impairment of immunosurveillance mechanisms. Despite recent success with immunotherapy treatment, disease progression still occurs quickly after treatment in the majority of cases, suggesting the need to improve patient selection strategies. In the quest for biomarkers that may help inform response to checkpoint blockade, we characterized the tumor microenvironment (TME) of 162 HNSCC primary tumors of diverse etiologic and spatial origin, through gene expression and IHC profiling of relevant immune proteins, T-cell receptor (TCR) repertoire analysis, and whole-exome sequencing. We identified five HNSCC TME categories based on immune/stromal composition: (i) cytotoxic, (ii) plasma cell rich, (iii) dendritic cell rich, (iv) macrophage rich, and (v) immune-excluded. Remarkably, the cytotoxic and plasma cell rich subgroups exhibited a phenotype similar to tertiary lymphoid structures (TLS), which have been previously linked to immunotherapy response. We also found an increased richness of the TCR repertoire in these two subgroups and in never smokers. Mutational patterns evidencing APOBEC activity were enriched in the plasma cell high subgroup. Furthermore, specific signal propagation patterns within the Ras/ERK and PI3K/AKT pathways associated with distinct immune phenotypes. While traditionally CD8/CD3 T-cell infiltration and immune checkpoint expression (e.g., PD-L1) have been used in the patient selection process for checkpoint blockade treatment, we suggest that additional biomarkers, such as TCR productive clonality, smoking history, and TLS index, may have the ability to pull out potential responders to benefit from immunotherapeutic agents. SIGNIFICANCE: Here we present our findings on the genomic and immune landscape of primary disease in a cohort of 162 patients with HNSCC, benefitting from detailed molecular and clinical characterization. By employing whole-exome sequencing and gene expression analysis of relevant immune markers, TCR profiling, and staining of relevant proteins involved in immune response, we highlight how distinct etiologies, cell intrinsic, and environmental factors combine to shape the landscape of HNSCC primary disease.

Olaparib and durvalumab in patients with relapsed small cell lung cancer (MEDIOLA): An open-label, multicenter, phase 1/2, basket study.

INTRODUCTION: Preclinical studies have demonstrated increased efficacy with combined DNA damage response inhibition and immune checkpoint blockade compared with either alone. We assessed olaparib in combination with durvalumab in patients with relapsed small cell lung cancer (SCLC). METHODS: Patients with previously treated limited or extensive-stage SCLC received oral olaparib 300 mg twice daily, as run-in for 4 weeks, then with durvalumab (1500 mg intravenously every 4 weeks) until disease progression. Primary endpoints were safety, tolerability, and 12-week disease control rate (DCR). Secondary endpoints included 28-week DCR, objective response rate (ORR), duration of response, progression-free survival, overall survival, change in tumor size, and programmed death-ligand 1 (PD-L1) expression subgroup analyses. RESULTS: Forty patients were enrolled and analyzed for safety; 38 were analyzed for efficacy. Eleven patients (28.9% [90% confidence interval (CI), 17.2-43.3]) had disease control at 12 weeks. ORR was 10.5% (95% CI, 2.9-24.8). Median progression-free and overall survival were 2.4 (95% CI, 0.9-3.0)months and 7.6(95% CI, 5.6-8.8)months, respectively. The most common adverse events (≥40.0%) were anemia, nausea, and fatigue. Grade ≥ 3 adverse events occurred in 32 patients (80.0%). PD-L1 levels, tumor mutational burden, and other genetic mutations were evaluated, but no significant correlations with clinical outcomes wereobserved. CONCLUSIONS: Tolerability of olaparib with durvalumab was consistent with the safety profile of each agent alone. Although the 12-week DCR did not meet the prespecified target (60%), four patients responded, and median overall survival was promising for a pretreated SCLC population. Further analyses are required to identify patients most likely to benefit from this treatment approach.

PARP inhibition is a modulator of anti-tumor immune response in BRCA-deficient tumors.

PARP inhibitors are synthetically lethal with BRCA1/2 mutations, and in this setting, accumulation of DNA damage leads to cell death. Because increased DNA damage and subsequent immune activation can prime an anti-tumor immune response, we studied the impact of olaparib ± immune checkpoint blockade (ICB) on anti-tumor activity and the immune microenvironment. Concurrent combination of olaparib, at clinically relevant exposures, with ICB gave durable and deeper anti-tumor activity in the Brca1m BR5 model vs. monotherapies. Olaparib and combination treatment modulated the immune microenvironment, including increases in CD8+ T cells and NK cells, and upregulation of immune pathways, including type I IFN and STING signaling. Olaparib also induced a dose-dependent upregulation of immune pathways, including JAK/STAT, STING and type I IFN, in the tumor cell compartment of a BRCA1m (HBCx-10) but not a BRCA WT (HBCx-9) breast PDX model. In vitro, olaparib induced BRCAm tumor cell-specific dendritic cell transactivation. Relevance to human disease was assessed using patient samples from the MEDIOLA (NCT02734004) trial, which showed increased type I IFN, STING, and JAK/STAT pathway expression following olaparib treatment, in line with preclinical findings. These data together provide evidence for a mechanism and schedule underpinning potential benefit of ICB combination with olaparib.

Retrospective analysis of Schlafen11 (SLFN11) to predict the outcomes to therapies affecting the DNA damage response.

BACKGROUND: The absence of the putative DNA/RNA helicase Schlafen11 (SLFN11) is thought to cause resistance to DNA-damaging agents (DDAs) and PARP inhibitors. METHODS: We developed and validated a clinically applicable SLFN11 immunohistochemistry assay and retrospectively correlated SLFN11 tumour levels to patient outcome to the standard of care therapies and olaparib maintenance. RESULTS: High SLFN11 associated with improved prognosis to the first-line treatment with DDAs platinum-plus-etoposide in SCLC patients, but was not strongly linked to paclitaxel-platinum response in ovarian cancer patients. Multivariate analysis of patients with relapsed platinum-sensitive ovarian cancer from the randomised, placebo-controlled Phase II olaparib maintenance Study19 showed SLFN11 tumour levels associated with sensitivity to olaparib. Study19 patients with high SLFN11 had a lower progression-free survival (PFS) hazard ratio compared to patients with low SLFN11, although both groups had the benefit of olaparib over placebo. Whilst caveated by small sample size, this trend was maintained for PFS, but not overall survival, when adjusting for BRCA status across the olaparib and placebo treatment groups, a key driver of PARP inhibitor sensitivity. CONCLUSION: We provide clinical evidence supporting the role of SLFN11 as a DDA therapy selection biomarker in SCLC and highlight the need for further clinical investigation into SLFN11 as a PARP inhibitor predictive biomarker.

A Phase 1 study of gefitinib combined with durvalumab in EGFR TKI-naive patients with EGFR mutation-positive locally advanced/metastatic non-small-cell lung cancer.

BACKGROUND: EGFR tyrosine kinase inhibitors (TKIs) induce cytolysis and release of tumour proteins, which can stimulate antigen-specific T cells. The safety and efficacy of durvalumab and gefitinib in combination for TKI-naive patients with advanced EGFRm NSCLC was evaluated. METHODS: This Phase 1 open-label, multicentre trial (NCT02088112) was conducted in 56 patients with NSCLC. Dose expansion permitted TKI-naive patients, primarily with activating L858R or Ex19del EGFRm. Arms 1 + 1a received concurrent therapy; Arm 2 received 4 weeks of gefitinib induction followed by concurrent therapy. RESULTS: From dose escalation, the recommended dose of durvalumab was 10 mg/kg Q2W with 250 mg QD gefitinib. Pharmacokinetics were as expected, consistent with inhibition of soluble PD-L1 and no treatment-emergent immunogenicity. In dose expansion, 35% of patients had elevated liver enzymes leading to drug discontinuation. In Arms 1 + 1a, objective response rate was 63.3% (95% CI: 43.9-80.1), median progression-free survival (PFS) was 10.1 months (95% CI: 5.5-15.2) and median response duration was 9.2 months (95% CI: 3.7-14.0). CONCLUSIONS: Durvalumab and gefitinib in combination had higher toxicity than either agent alone. No significant increase in PFS was detected compared with historical controls. Therefore, concurrent PD-L1 inhibitors with gefitinib should be generally avoided in TKI-naive patients with EGFRm NSCLC.

Olaparib and durvalumab in patients with germline BRCA-mutated metastatic breast cancer (MEDIOLA): an open-label, multicentre, phase 1/2, basket study.

BACKGROUND: Poly (ADP-ribose) polymerase inhibitors combined with immunotherapy have shown antitumour activity in preclinical studies. We aimed to assess the safety and activity of olaparib in combination with the PD-L1-inhibitor, durvalumab, in patients with germline BRCA1-mutated or BRCA2-mutated metastatic breast cancer. METHODS: The MEDIOLA trial is a multicentre, open-label, phase 1/2, basket trial of durvalumab and olaparib in solid tumours. Patients were enrolled into four initial cohorts: germline BRCA-mutated, metastatic breast cancer; germline BRCA-mutated, metastatic ovarian cancer; metastatic gastric cancer; and relapsed small-cell lung cancer. Here, we report on the cohort of patients with breast cancer. Patients who were aged 18 years or older (or aged 19 years or older in South Korea) with germline BRCA1-mutated or BRCA2-mutated or both and histologically confirmed, progressive, HER2-negative, metastatic breast cancer were enrolled from 14 health centres in the UK, the USA, Israel, France, Switzerland, and South Korea. Patients should not have received more than two previous lines of chemotherapy for metastatic breast cancer. Patients received 300 mg olaparib in tablet form orally twice daily for 4 weeks and thereafter a combination of olaparib 300 mg twice daily and durvalumab 1·5 g via intravenous infusion every 4 weeks until disease progression. Primary endpoints were safety and tolerability, and 12-week disease control rate. Safety was analysed in patients who received at least one dose of study treatment, and activity analyses were done in the full-analysis set (patients who received at least one dose of study treatment and were not excluded from the study). Recruitment has completed and the study is ongoing. This trial is registered with ClinicalTrials.gov, NCT02734004. FINDINGS: Between June 14, 2016, and May 2, 2017, 34 patients were enrolled and received both study drugs and were included in the safety analysis. 11 (32%) patients experienced grade 3 or worse adverse events, of which the most common were anaemia (four [12%]), neutropenia (three [9%]), and pancreatitis (two [6%]). Three (9%) patients discontinued due to adverse events and four (12%) patients experienced a total of six serious adverse events. There were no treatment-related deaths. 24 (80%; 90% CI 64·3-90·9) of 30 patients eligible for activity analysis had disease control at 12 weeks. INTERPRETATION: Combination of olaparib and durvalumab showed promising antitumour activity and safety similar to that previously observed in olaparib and durvalumab monotherapy studies. Further research in a randomised setting is needed to determine predictors of therapeutic benefit and whether addition of durvalumab improves long-term clinical outcomes compared with olaparib monotherapy. FUNDING: AstraZeneca.

The immune contexture and Immunoscore in cancer prognosis and therapeutic efficacy.

The international American Joint Committee on Cancer/Union for International Cancer Control (AJCC/UICC) tumour-node-metastasis (TNM) staging system provides the current guidelines for the classification of cancer. However, among patients within the same stage, the clinical outcome can be very different. More recently, a novel definition of cancer has emerged, implicating at all stages a complex and dynamic interaction between tumour cells and the immune system. This has enabled the definition of the immune contexture, representing the pre-existing immune parameters associated with patient survival. Even so, the role of distinct immune cell types in modulating cancer progression is increasingly emerging. An immune-based assay named the 'Immunoscore' was defined to quantify the in situ T cell infiltrate and was demonstrated to be superior to the AJCC/UICC TNM classification for patients with colorectal cancer. This Review provides a broad overview of the main immune parameters positively or negatively shaping cancer development, including the Immunoscore, and their prognostic and predictive value. The importance of the immune system in cancer control is demonstrated by the requirement for a pre-existing intratumour adaptive immune response for effective immunotherapies, such as checkpoint inhibitors. Finally, we discuss how the combination of multiple immune parameters, rather than individual ones, might increase prognostic and/or predictive power.

The Immunoscore: Colon Cancer and Beyond.

Tumors evolve in close interaction with their microenvironment, which encompasses a continual tension between the developing tumor and the host immune system. Clinical trials have shown that appropriate enhancement of a tumor immune response can lead to long-lasting clinical responses and patient benefit. Understanding the contribution of the immune contexture, in addition to the molecular subtype across different tumor indications, is a significant knowledge gap with limited sagacity to drive rational immunotherapy combinations. To better inform clinical studies, we must first strive to understand the multifaceted elements of the tumor-immune interaction, the spatiotemporal interplay of numerous different immune cell types, in conjunction with an understanding of the oncogenic drivers and mutations that may lead to presentation of neoepitopes and could drive changes within the tumor microenvironment. In this review, we discuss the Immunoscore and its probable universal characteristic. The overlay of immune quantification with the molecular segments of disease and how this may benefit identification of patients at high risk of tumor recurrence will be discussed. The Immunoscore may translate to provide a tumor agnostic method to define immune fitness of a given tumor and predict and stratify patients who will benefit from certain therapies (in particular immune therapies) and, ultimately, help save the lives of patients with cancer.

Modulation of Biomarker Expression by Osimertinib: Results of the Paired Tumor Biopsy Cohorts of the AURA Phase I Trial.

INTRODUCTION: Osimertinib is an oral, potent, irreversible EGFR tyrosine kinase inhibitor (TKI) selective for EGFR TKI and T790M resistance mutations. To enhance understanding of osimertinib's mechanism of action, we aimed to evaluate the modulation of key molecular biomarkers after osimertinib treatment in paired clinical samples from the phase I AURA trial. METHODS: Paired tumor biopsy samples were collected before the study and after 15 plus or minus 7 days of osimertinib treatment (80 or 160 mg daily). Clinical efficacy outcomes were assessed according to whether viable paired biopsy samples could be collected; safety was also assessed. Immunohistochemical analyses assessed key pathway and tumor/immune-relevant markers (phospho-EGFR, phospho-S6, phospho-AKT, programmed death ligand 1, and CD8), with samples scored by image analysis or a pathologist blinded to treatment allocation. RESULTS: Predose tumor biopsy samples were collected from 61 patients with EGFR T790M tumors; 29 patients had no viable postdose biopsy sample because of tumor regression or insufficient tumor sample. Evaluable predose and postdose tumor biopsy samples were collected from 24 patients. Objective response rate (ORR) and median progression-free survival (mPFS) were improved in patients from whom a postdose biopsy sample could not be collected (ORR 62% and mPFS 9.7 months [p = 0.027]) compared with those from whom paired samples were collected (ORR 29% and mPFS 6.6 months). Osimertinib modulated key EGFR signaling pathways and led to increased immune cell infiltration. CONCLUSIONS: Collection of paired biopsy samples was challenging because of rapid tumor regression after osimertinib treatment, highlighting the difficulties of performing on-study biopsies in patients treated with highly active drugs.

Integrative Analyses of Colorectal Cancer Show Immunoscore Is a Stronger Predictor of Patient Survival Than Microsatellite Instability.

Microsatellite instability in colorectal cancer predicts favorable outcomes. However, the mechanistic relationship between microsatellite instability, tumor-infiltrating immune cells, Immunoscore, and their impact on patient survival remains to be elucidated. We found significant differences in mutational patterns, chromosomal instability, and gene expression that correlated with patient microsatellite instability status. A prominent immune gene expression was observed in microsatellite-instable (MSI) tumors, as well as in a subgroup of microsatellite-stable (MSS) tumors. MSI tumors had increased frameshift mutations, showed genetic evidence of immunoediting, had higher densities of Th1, effector-memory T cells, in situ proliferating T cells, and inhibitory PD1-PDL1 cells, had high Immunoscores, and were infiltrated with mutation-specific cytotoxic T cells. Multivariate analysis revealed that Immunoscore was superior to microsatellite instability in predicting patients' disease-specific recurrence and survival. These findings indicate that assessment of the immune status via Immunoscore provides a potent indicator of tumor recurrence beyond microsatellite-instability staging that could be an important guide for immunotherapy strategies.

The tumor microenvironment and Immunoscore are critical determinants of dissemination to distant metastasis.

Although distant metastases account for most of the deaths in cancer patients, fundamental questions regarding mechanisms that promote or inhibit metastasis remain unanswered. We show the impact of mutations, genomic instability, lymphatic and blood vascularization, and the immune contexture of the tumor microenvironment on synchronous metastases in large cohorts of colorectal cancer patients. We observed large genetic heterogeneity among primary tumors, but no major differences in chromosomal instability or key cancer-associated mutations. Similar patterns of cancer-related gene expression levels were observed between patients. No cancer-associated genes or pathways were associated with M stage. Instead, mutations of FBXW7 were associated with the absence of metastasis and correlated with increased expression of T cell proliferation and antigen presentation functions. Analyzing the tumor microenvironment, we observed two hallmarks of the metastatic process: decreased presence of lymphatic vessels and reduced immune cytotoxicity. These events could be the initiating factors driving both synchronous and metachronous metastases. Our data demonstrate the protective impact of the Immunoscore, a cytotoxic immune signature, and increased marginal lymphatic vessels, against the generation of distant metastases, regardless of genomic instability.

Correlation between Density of CD8+ T-cell Infiltrate in Microsatellite Unstable Colorectal Cancers and Frameshift Mutations: A Rationale for Personalized Immunotherapy.

Colorectal cancers with microsatellite instability (MSI) represent 15% of all colorectal cancers, including Lynch syndrome as the most frequent hereditary form of this disease. Notably, MSI colorectal cancers have a higher density of tumor-infiltrating lymphocytes (TIL) than other colorectal cancers. This feature is thought to reflect the accumulation of frameshift mutations in sequences that are repeated within gene coding regions, thereby leading to the synthesis of neoantigens recognized by CD8(+) T cells. However, there has yet to be a clear link established between CD8(+) TIL density and frameshift mutations in colorectal cancer. In this study, we examined this link in 103 MSI colorectal cancers from two independent cohorts where frameshift mutations in 19 genes were analyzed and CD3(+), CD8(+), and FOXP3(+) TIL densities were quantitated. We found that CD8(+) TIL density correlated positively with the total number of frameshift mutations. TIL densities increased when frameshift mutations were present within the ASTE1, HNF1A, or TCF7L2 genes, increasing even further when at least one of these frameshift mutations was present in all tumor cells. Through in vitro assays using engineered antigen-presenting cells, we were able to stimulate peripheral cytotoxic T cells obtained from colorectal cancer patients with peptides derived from frameshift mutations found in their tumors. Taken together, our results highlight the importance of a CD8(+) T cell immune response against MSI colorectal cancer-specific neoantigens, establishing a preclinical rationale to target them as a personalized cellular immunotherapy strategy, an especially appealing goal for patients with Lynch syndrome.

The immune landscape of human tumors: Implications for cancer immunotherapy.

Understanding the spontaneous immune response of cancer patients is critical for the design of efficient anticancer immunotherapies. The power of integrative tumor immunology approaches allowed for a comprehensive view of the immune system evolution in the course of tumor progression and recurrence. We have demonstrated that tumor-infiltrating immune cells are spatiotemporally regulated, a finding that has profound implications for the development of efficient anticancer immunotherapies.

[Intratumoral immune microenvironment and survival: the immunoscore]. / Microenvironnement immunitaire et cancer - intérêt de l'immunoscore pour prédire l'évolution clinique.

The natural history of cancer involves interactions between the tumor and the host immune system. In humans, clinical and experimental data support the existence of a natural immune response against cancer. We provided evidence that the type, the density and the location of immune cells within the tumor strongly influence the prognosis, independently of the TNM classification. We established a methodology named "immunoscore" to assess in clinical practice the immune infiltrate. An international consortium of expert laboratories is currently testing the immunoscore in routine clinical settings for cancer classification. The availability of the mmunoscore could significantly improve the prognostic assessment of patients and better guide the therapeutic decision. This could result in the implementation of the immunoscore as a new component for the classification of cancer, designated TNM-I (TNM-immune).

Functional network pipeline reveals genetic determinants associated with in situ lymphocyte proliferation and survival of cancer patients.

The tumor microenvironment is host to a complex network of cytokines that contribute to shaping the intratumoral immune reaction. Chromosomal gains and losses, coupled with expression analysis, of 59 cytokines and receptors and their functional networks were investigated in colorectal cancers. Changes in local expression for 13 cytokines were shown. Metastatic patients exhibited an increased frequency of deletions of cytokines from chromosome 4. Interleukin 15 (IL15) deletion corresponded with decreased IL15 expression, a higher risk of tumor recurrence, and reduced patient survival. Decreased IL15 expression affected the local proliferation of B and T lymphocytes. Patients with proliferating B and T cells at the invasive margin and within the tumor center had significantly prolonged disease-free survival. These results delineate chromosomal instability as a mechanism of modulating local cytokine expression in human tumors and underline the major role of IL15. Our data provide further mechanisms resulting in changes of specific immune cell densities within the tumor, and the importance of local active lymphocyte proliferation for patient survival.

Towards the introduction of the 'Immunoscore' in the classification of malignant tumours.

The American Joint Committee on Cancer/Union Internationale Contre le Cancer (AJCC/UICC) TNM staging system provides the most reliable guidelines for the routine prognostication and treatment of colorectal carcinoma. This traditional tumour staging summarizes data on tumour burden (T), the presence of cancer cells in draining and regional lymph nodes (N) and evidence for distant metastases (M). However, it is now recognized that the clinical outcome can vary significantly among patients within the same stage. The current classification provides limited prognostic information and does not predict response to therapy. Multiple ways to classify cancer and to distinguish different subtypes of colorectal cancer have been proposed, including morphology, cell origin, molecular pathways, mutation status and gene expression-based stratification. These parameters rely on tumour-cell characteristics. Extensive literature has investigated the host immune response against cancer and demonstrated the prognostic impact of the in situ immune cell infiltrate in tumours. A methodology named 'Immunoscore' has been defined to quantify the in situ immune infiltrate. In colorectal cancer, the Immunoscore may add to the significance of the current AJCC/UICC TNM classification, since it has been demonstrated to be a prognostic factor superior to the AJCC/UICC TNM classification. An international consortium has been initiated to validate and promote the Immunoscore in routine clinical settings. The results of this international consortium may result in the implementation of the Immunoscore as a new component for the classification of cancer, designated TNM-I (TNM-Immune).

Spatiotemporal dynamics of intratumoral immune cells reveal the immune landscape in human cancer.

The complex interactions between tumors and their microenvironment remain to be elucidated. Combining large-scale approaches, we examined the spatio-temporal dynamics of 28 different immune cell types (immunome) infiltrating tumors. We found that the immune infiltrate composition changed at each tumor stage and that particular cells had a major impact on survival. Densities of T follicular helper (Tfh) cells and innate cells increased, whereas most T cell densities decreased along with tumor progression. The number of B cells, which are key players in the core immune network and are associated with prolonged survival, increased at a late stage and showed a dual effect on recurrence and tumor progression. The immune control relevance was demonstrated in three endoscopic orthotopic colon-cancer mouse models. Genomic instability of the chemokine CXCL13 was a mechanism associated with Tfh and B cell infiltration. CXCL13 and IL21 were pivotal factors for the Tfh/B cell axis correlating with survival. This integrative study reveals the immune landscape in human colorectal cancer and the major hallmarks of the microenvironment associated with tumor progression and recurrence.

The continuum of cancer immunosurveillance: prognostic, predictive, and mechanistic signatures.

Numerous analyses of large patient cohorts identified specific patterns of immune activation associated with patient survival. We established these as the immune contexture, encompassing the type, functional orientation, density, and location of adaptive immune cells within distinct tumor regions. Based on the immune contexture, a standardized, powerful immune stratification system, the Immunoscore, was delineated. The immune contexture is characterized by immune signatures also observed in association with the broader phenomenon of immune-mediated, tissue-specific destruction. We defined these as the immunologic constant of rejection. Predictive, prognostic, and mechanistic immune signatures overlap, and a continuum of intratumor immune reactions exists. The balance between tumor cell growth and elimination may be tipped upon a crescendo induced by immune manipulations aimed at enhancing naturally occurring immunosurveillance. Here, we propose a broader immunological interpretation of these three concepts--immune contexture, Immunoscore, and immunologic constant of rejection--that segregates oncogenic processes independently of their tissue origin.

From the immune contexture to the Immunoscore: the role of prognostic and predictive immune markers in cancer.

The inherent complexity of multifactorial diseases such as cancer renders the process of patient prognosis and prediction of response to therapy extremely difficult. Many markers, signatures, and methods have been described to evaluate the prognosis of cancer patients, yet very few translate into the clinic. Systems biology approaches have facilitated analysis of the complex interaction between tumors and the host-immune response, and allowed the definition of the immune contexture. Here we review the potential of the immune contexture, quantified by the Immunoscore, to provide a statistically strong parameter for prognosis. Finally we introduce the concept that the host-immune reaction could be the critical element in determining response to therapy. The effect on the immune response could be the underlying factor behind many of the predictive markers.

Cancer classification using the Immunoscore: a worldwide task force.

Prediction of clinical outcome in cancer is usually achieved by histopathological evaluation of tissue samples obtained during surgical resection of the primary tumor. Traditional tumor staging (AJCC/UICC-TNM classification) summarizes data on tumor burden (T), presence of cancer cells in draining and regional lymph nodes (N) and evidence for metastases (M). However, it is now recognized that clinical outcome can significantly vary among patients within the same stage. The current classification provides limited prognostic information, and does not predict response to therapy. Recent literature has alluded to the importance of the host immune system in controlling tumor progression. Thus, evidence supports the notion to include immunological biomarkers, implemented as a tool for the prediction of prognosis and response to therapy. Accumulating data, collected from large cohorts of human cancers, has demonstrated the impact of immune-classification, which has a prognostic value that may add to the significance of the AJCC/UICC TNM-classification. It is therefore imperative to begin to incorporate the 'Immunoscore' into traditional classification, thus providing an essential prognostic and potentially predictive tool. Introduction of this parameter as a biomarker to classify cancers, as part of routine diagnostic and prognostic assessment of tumors, will facilitate clinical decision-making including rational stratification of patient treatment. Equally, the inherent complexity of quantitative immunohistochemistry, in conjunction with protocol variation across laboratories, analysis of different immune cell types, inconsistent region selection criteria, and variable ways to quantify immune infiltration, all underline the urgent requirement to reach assay harmonization. In an effort to promote the Immunoscore in routine clinical settings, an international task force was initiated. This review represents a follow-up of the announcement of this initiative, and of the J Transl Med. editorial from January 2012. Immunophenotyping of tumors may provide crucial novel prognostic information. The results of this international validation may result in the implementation of the Immunoscore as a new component for the classification of cancer, designated TNM-I (TNM-Immune).