Cancer classification using the Immunoscore: a worldwide task force

Abstract

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).

Microenvironnement immunitaire et cancer

“…Pour des évaluations immunitaires de routine, un test simple a été proposé, appelé immunoscore. Une validation internationale de l'immunoscore est actuellement en cours de réalisation afin d'intégrer ce nouveau paramètre à la classification TNM des cancers et aboutir à une classification de type TNM-I (TNM-immune) [25]. En outre, la contexture immunitaire et l'immunoscore pourraient permettre de prédire la réponse à de nombreuses thérapies [22].…”

“…Une partie de l'explication de la pré-pondérance statistique de l'immunoscore pourrait être que la densité de l'infiltrat CD8 + est inversement corrélée avec le stade T dans les tumeurs qui ne vont pas récidiver, tandis que la densité en cellules T CD8 est faible, même au sein de cancers peu invasifs, dans le groupe de tumeurs qui vont réci-diver [23]. Ainsi, l'intégration de l'immunoscore dans la classification des cancers pourrait se traduire par une amélioration de la précision du pronostic, mais aussi, potentiellement, de la prédiction de la réponse aux traitements [25,26]. Un bon marqueur pronostique doit être réalisable en routine clinique, simple, peu coûteux, rapide, robuste, reproductible, quantitatif, et puissant.…”

“…Un bon marqueur pronostique doit être réalisable en routine clinique, simple, peu coûteux, rapide, robuste, reproductible, quantitatif, et puissant. L'immunoscore pourrait répondre à ces exigences [25].…”

Causality, Information, and Biological Computation: An Algorithmic Software Approach to Life, Disease, and the Immune System

“…Interestingly, these two highly complex systems are interconnected -the immune system plays a key role in tumour development: The immune status ("immunoscore") was found to be the highly predictive for cancer patient survival [15], and evading immune destruction was added to the "hallmarks of cancer" recently [17]. According to the immune surveillance theory, the immune system does not only recognise and combat invading pathogens but also detects host cells that become cancerous, thus eliminating tumor cells as soon as they arise.…”

Glioma and glioblastoma - how much do we (not) know?

“…Such a system is the TNM staging system, where 'T' stands for tumor, 'N' for lymph nodes and 'M' for metastasis. Thus far, five stages have been described (6) (Table I).…”