title: Micrometastatic P53-positive cells in the lymph nodes of non-small-cell lung cancer: prognostic significance.
abstract: OBJECTIVE
  Approximately one fourth of all patients with stage I non-small-cell lung cancer die of tumor recurrence, despite radical removal of their tumors. We thus tried to detect micrometastasis in the regional lymph nodes indicated to be tumor free by conventional histopathologic methods in patients with non-small-cell lung cancer by using immunohistochemical staining for p53 protein. We also investigated the relation between micrometastatic p53-positive cells in the lymph nodes and the prognosis of the patients.
  
  
  METHODS
  Samples from 480 regional lymph nodes were taken from 47 patients who underwent pulmonary resection for non-small-cell lung cancer and whose primary lesions were positive for p53 immunohistochemical staining. These samples were fixed in formalin and embedded in paraffin. We used p53 immunohistochemical staining to detect micrometastatic tumor cells in the lymph nodes.
  
  
  RESULTS
  Cells positive for p53 protein were found in 14 of 31 (45%) patients with a negative pathologic lymph node status and in 26 of 315 (8.3%) lymph nodes in these patients. The proportion of patients with micrometastasis who survived was also significantly lower than the proportion of patients without micrometastasis who survived (p = 0.0001).
  
  
  CONCLUSIONS
  Immunohistochemical staining for the p53 protein offers a rapid, sensitive, and useful way of detecting for micrometastasis to the regional lymph nodes in patients with non-small-cell lung cancer that is positive for p53 staining. The patients with such micrometastases have a poor prognosis and thus need to be carefully followed up after the initial pulmonary resection.
authors.affiliation: Department of Surgery II, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Dobashi
authors.forename: K
authors.initials: K
authors.lastname: Sugio
authors.forename: T
authors.initials: T
authors.lastname: Osaki
authors.forename: T
authors.initials: T
authors.lastname: Oka
authors.forename: K
authors.initials: K
authors.lastname: Yasumoto
mesh_terms: D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics / Q000378:metabolism / Q000401:mortality / Q000556:secondary*; D016022:Case-Control Studies; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D008175:Lung Neoplasms / Q000235:genetics / Q000401:mortality / Q000473:pathology*; D008198:Lymph Nodes / Q000737:chemistry* / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016019:Survival Analysis; D016159:Tumor Suppressor Protein p53 / Q000032:analysis*
chemical_list: D016159:Tumor Suppressor Protein p53