title: In situ evidence of neoplastic cell phagocytosis by macrophages in papillary thyroid cancer.
abstract: We evaluated the occurrence, tissue distribution, and prognostic value of tumor-associated macrophages in 121 papillary thyroid carcinomas using immunohistochemical staining with anti-CD68 antibody in archival paraffin-embedded sections. Lymphocytic infiltration and dendritic cell presence were also evaluated. Three groups were identified according to the presence and characteristics of macrophages: 1) tumors without evidence of infiltrating macrophages: (n = 35); 2) tumors with infiltrating macrophages but no evidence of neoplastic cells phagocytosis (n = 68); and 3) tumors with infiltrating macrophages and in situ evidence of active neoplastic cell phagocytosis (n = 18). Neoplastic cell phagocytosis by macrophages was positively correlated with both lymphocytic infiltration and dendritic cells (P = 0.0000), whereas it was negatively correlated with vascular invasion (P = 0.0032). Distant metastases developed in none of the 18 tumors with neoplastic cell phagocytosis, but occurred in 15 of 103 of the remaining tumors (P = 0.0647) and were significantly and negatively associated with lymphocytic infiltration or dendritic cells. The present study indicates, therefore, that immune reaction, involving neoplastic cell phagocytosis by macrophages and lymphocytic infiltration, plays a role in the development of distant metastases in patients with papillary thyroid cancer.
authors.affiliation: Servizio di Anatomia ed Istologia Patologica, Presidio Ospedaliero Vittorio Emanuele II, Catania, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Fiumara
authors.forename: A
authors.initials: A
authors.lastname: Belfiore
authors.forename: G
authors.initials: G
authors.lastname: Russo
authors.forename: E
authors.initials: E
authors.lastname: Salomone
authors.forename: G M
authors.initials: GM
authors.lastname: Santonocito
authors.forename: O
authors.initials: O
authors.lastname: Ippolito
authors.forename: R
authors.initials: R
authors.lastname: Vigneri
authors.forename: P
authors.initials: P
authors.lastname: Gangemi
mesh_terms: D000328:Adult; D002291:Carcinoma, Papillary / Q000276:immunology* / Q000473:pathology; D003713:Dendritic Cells / Q000473:pathology; D005260:Female; D006801:Humans; D008214:Lymphocytes / Q000473:pathology; D008264:Macrophages / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D010587:Phagocytosis; D013964:Thyroid Neoplasms / Q000276:immunology* / Q000473:pathology; D013967:Thyroiditis, Autoimmune / Q000276:immunology