The sentinel lymph node (SN) is the first node on the direct lymphatic drainage pathway from a @entity5 . @entity320 -associated SNs are the most likely site of early @entity3 and their immune functions are strikingly down-modulated. We evaluated histologic and cytologic characteristics of 21 SNs and 21 nonsentinel nodes (NSNs) from @entity320 @entity1 who had clinically localized (AJCC Stage I--II) primary @entity320 . SNs showed highly significant reductions in total paracortical area and in the area of the paracortical subsector occupied by dendritic cells. The frequency of paracortical interdigitating dendritic cells (IDCs) was dramatically reduced in SNs, and most IDCs (approximately 99%) lacked the complex dendrites associated with active antigen presentation. The release of immunosuppressive factors from the primary @entity320 may induce a localized and specific @entity912 in the SN, which prevents the recognition of otherwise immunogenic @entity320 antigens by IDCs. This immune @entity912 may facilitate the implantation and growth of @entity320 cells in the SN. Cytokine therapy may be able to reverse this immune @entity912 . These findings have an important practical application in the histopathologic confirmation that a node is truly sentinel. They also offer an hypothesis to explain the failure of the immune surveillance mechanisms to identify and respond to a small primary @entity320 that expresses @entity5 antigens.

Sentinel lymph nodes show profound downregulation of antigen-presenting cells of the paracortex: implications for XXXX biology and treatment.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity912 :: ('MESH:D010243', 'Disease') :: ['paralysis'] @entity5 :: ('MESH:D009369', 'Disease') :: ['tumor', 'immunogenic tumor'] @entity3 :: ('MESH:D009362', 'Disease') :: ['metastases'] @entity320 :: ('MESH:D008545', 'Disease') :: ['melanoma', 'cutaneous melanoma', 'Melanoma']
@entity5 :: (MESH:D009369,Disease) :: ['tumor']
