Open AccessInnate Immune Reactions in Locally Early Tonsillar Cancer
Author(s) -
Kuratomi Yuichiro,
Kusano Kenichiro,
Shimazu Rintaro,
Inokuchi Akira
Publication year - 2012
Publication title -
otolaryngology–head and neck surgery
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.232
H-Index - 121
eISSN - 1097-6817
pISSN - 0194-5998
DOI - 10.1177/0194599812451426a117
Subject(s) - tonsil , innate immune system , immune system , tongue , medicine , cancer , palatine tonsil , pathology , primary tumor , antibody , cd68 , innate lymphoid cell , immunohistochemistry , immunology , metastasis
Objective The palatine tonsil contains innate immune cells such as natural killer (NK) cells and macrophages. Tonsillar cancers often present locally early tumors with cervical metastases. This study was performed to clarify the possibility that the growth of primary tumors might be inhibited by innate immune cells in the palatine tonsil. Method NK cells and macrophages were immunohistochemically identified using anti‐HNK‐1 and anti‐CD68 antibodies. The degree of the immune cell infiltration in tonsillar cancers, tongue cancers, and normal tonsils was estimated by counting the number of NK cells and macrophages in formalin‐fixed, paraffin‐embedded blocks. Phagocytosis of the tumor cells was also studied. Results There was a significant increase in the number of NK cells in locally early tonsillar cancers (a median of 100 in 8 patients) in comparison to locally early tongue cancers (a median of 8 in 15 patients) and 5 normal tonsils (a median of 35; P <. 0001). The number of macrophages was also significantly increased in tonsillar cancers (a median of 247) in comparison to tongue cancers (a median of 81) and normal tonsils (a median of 82; P <. 0001). Phagocytosis of tumor cells by macrophages was observed significantly more frequently in tonsillar cancers than in tongue cancers ( P <. 01). Conclusion The innate immune reactions were observed to significantly increase and they might therefore inhibit the growth of the primary tumor in locally early tonsillar cancer. In addition, these inhibitory immune reactions against the primary tumor in the palatine tonsil might be part of the etiology of developing primary‐unknown cervical metastasis.