Int J Clin Exp Pathol 2014;7(4):XXX-XXX www.ijcep.com /ISSN:1936-2625/IJCEP1402033 Letter to Editor Tissue Micro Arrays for immunohistochemical detection of inlammatory iniltrates in renal cell carcinoma Giosuè Scognamiglio 1 , Monica Cantile 1 , Stefania Scala 2 , Sabrina Cecere 3 , Federica Russo 1 , Francesca Collina 1 , Laura Marra 1 , Francesco Sabbatino 4 , Gerardo Botti 1 , Renato Franco 1 1 Pathology Unit, Istituto Nazionale Tumori Fondazione “G. Pascale”, via Mariano Semmola, Naples, 80131 Italy; 2 Department of Oncological Immunology, Istituto Nazionale Tumori Fondazione “G. Pascale”, via Mariano Sem- mola, Naples, 80131 Italy; 3 Department of Medical Oncology, Istituto Nazionale Tumori Fondazione “G. Pascale”, via Mariano Semmola, Naples, 80131 Italy; 4 Department of Surgery, Massachusetts General Hospital, Boston, 02114 MA, USA Received February 11, 2014; Accepted March 8, 2014; Epub XXX, 2014; Published XXX, 2014 The formation and “transformation” of a tissue is guaranteed by a dynamic interaction between cells and surrounding microenvironment which results to be constituted by extracellular matrix, ibroblasts, vascular cells, and immune cells. Inlammation that is characterized by tumor- iniltrating lymphocytes (TIL), macrophages tumor-associated (TAM), cells of myeloid origin with suppressive capacity (Myeloid derived suppressor cells MDSC) and dendritic cells (DC), plays a major role in cancer progression. Several are the mechanisms of tumor immune escape. Recent clinical trials have demonstrat- ed that administration of monoclonal antibod- ies (mAb) which inhibit the interaction of immune regulatory checkpoint molecules such as Cytotoxic T-Lymphocyte Antigen 4 ( CTLA-4) and Programmed cell death protein 1 (PD-1) with their ligands CD80, CD86 and Programmed cell death 1 ligand 1 ( PD- L1), can have a major and lasting effect on the clinical course of sev- eral malignant diseases including renal cell car- cinoma. Based on these indings, besides the classical diagnostic parameters, it is becoming essential to identify immunological biomarkers in order to predict the clinical course of the dis- ease and especially the response to the treatment. Renal cell carcinoma (RCC) is one of the most common disease in the urologic tract with more than 30% of patients with metastatic disease at diagnosis. In RCC, as well as in other immunogenic tumors such as melanoma [1], the role of the microenvi- ronment in the regulation of the mechanisms of tumor progression is well determined. RCC is deined as an immunogenic tumor since several evidence indicate a tumor immune response. Furthermore many therapeutic strategies based on the depletion of immune suppressive regulatory cell types which operate in RCC microenvironment as well as the inhibition of immune regulatory checkpoint molecules have been thoroughly described. RCC immune iniltrate may be characterized by different subpopulations of leukocyte iniltrate. Speciically, DCs have been shown to play an important role in RCC tumor immunity. Iniltration of DCs into RCC tumor has been associated with improved patients survival and reduced risk of disease recurrence [2]. Moreover, immune iniltrate of RCC has been also characterized by the presence of a large numbers of MDSCs and TAMs. TAM iniltration has been involved in cancer progression by stimulating angiogenesis, tumor growth, cellu- lar migration and invasion as well as metastatic potential and resistance to targeted agents [2]. In addition as well as for many types of solid tumors TILs have been also described in RCC tumor microenvironment being an important prognostic factor. TILs may be represented by CD20+ T cells. CD20 is a speciic antigen for B