Table 1 Characteristics of a good marker and of the Immunoscore [8]

Routine

Technic to be performed by pathologist using bright field and precise cell evaluation

Feasible

Established pathology technics, using 2 regular whole slide FFPE section

Inexpensive

Automatized immunohistochemistry

Rapid

2 simple staining less costly than complicated molecular techniques

Robust

Autostainers, scanner, and digital pathology reduce the time to perform an Immunoscore

Reproducible

Two strong membrane staining, with no background, allowing the numeration of individual cells

Quantitative

Inter-observers variability is removed by the use of digital pathology, taking into account cell location and counts

Standardized

Standardized operating procedure should be performed to insure reproducibility and worldwide comparisons

Pathology-based

Necessity of pathologist expertise to validate cell type, cell location, and cell counts performed by digital pathology

Powerful

The Immunoscore has a prognostic value highly significant even in Cox multivariate including TNM classification