title: Lymphocytic infiltration in undifferentiated nasopharyngeal cancer.
abstract: BACKGROUND
  Undifferentiated nasopharyngeal carcinoma (NPC) is characterized by prominent lymphocytic infiltration. Although the lymphoid infiltrate in NPC has been examined extensively in morphologic and immunocytochemical studies, the significance of this lymphoid infiltrate and its correlation with prognosis has been a subject of controversy for years.
  
  
  OBJECTIVE
  To elucidate the significance of lymphoid infiltration in undifferentiated NPC.
  
  
  METHODS
  Evaluation of the relationship between lymphocytic infiltration in NPC and cervical lymph node status, ultrastructural examination of the lymphoid infiltrate, and assessment of lymphocytic infiltration as an independent prognosticator of regional node metastasis.
  
  
  METHODS
  Lymphocytic infiltration was evaluated quantitatively in 20 cases of undifferentiated NPC using light microscopy. Four cases of undifferentiated NPC were processed for conventional electron microscopy. The effects of degree of lymphocytic infiltration, age, and tumor stage on cervical nodal metastasis were analysed using the logistic regression model.
  
  
  RESULTS
  The degree of lymphoid infiltration correlated with cervical nodal metastasis (P<.001). Ultrastructural evidence of lymphocytes destroying cancer cells was seen. Lymphocytic infiltration was found to be an independent factor affecting cervical nodal metastasis (P =.02, univariate analysis; P =.03, multivariate analysis).
  
  
  CONCLUSIONS
  The lymphoid infiltrate is beneficial in undifferentiated NPC, and its presence may deter regional metastasis of cancer cells to the cervical nodes.
authors.affiliation: Department of Anatomy, National University of Singapore, BLK MD10, 4 Medical Dr, S117597, Singapore.
authors.forename: A
authors.initials: A
authors.lastname: Jayasurya
authors.forename: B H
authors.initials: BH
authors.lastname: Bay
authors.forename: W M
authors.initials: WM
authors.lastname: Yap
authors.forename: N G
authors.initials: NG
authors.lastname: Tan
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008214:Lymphocytes / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000473:pathology*; D009367:Neoplasm Staging; D011379:Prognosis