Disseminated tumor cells in lymph nodes as a determinant for survival in surgically resected non-small-cell lung cancer

Purpose: In recent ears,the detection of even a few tumor cells in lymph no es of patients with surgically resected non-small-cell lung cancer (NSCLC) became possible with immunohistochemical staining procedures. Tumor cells i n lymph nodes have been shown to be associated with an increased rate of ea rly recurrence. However, the prognostic significance of this minimal tumor cell spread for overall survival remains unclear. Patients and Methods: We used the epithelium-specific monoclonal antibody B er-EP4, which recognises the 17-1A antigen (also called EGP40 or Ep-CAM), t o discover small tumor cell deposits (less than or equal to three cells) in 565 regional lymph nodes judged as rumor-free by conventional histopatholo gy in patients with NSCLC staged as pT1-4, pNO-2, MO, RO. In a prospective analysis, we studied the influence of the detected tumor cells on the cance r recurrence rate and survival of 117 patients. Results: Ber-EP4-positive c ells were found in 27 of 125 patients (21.6%). After an observation period of 64 months, patients with disseminated tumor cells had reduced disease-fr ee survival (P < .0001) and overall survival (P = .0001) rates in univariat e analyses (log-rank test). Multivariate analysis (Cox model) showed a 2.7 times increased risk for tumor relapse and a 2.5 times increased risk for s horter survival in patients with disseminated tumor cells compared with pat ients without such cells. Patients without any evidence of histopathologic and immunohistochemical lymph node involvement had an overall survival rate of 78%, Conclusion: The immunohistochemical detection of disseminated tumor cells i n lymph nodes of patients with completely resected NSCLC is an independent prognostic factor far overall survival. J Clin Oncol 17:19-24. (C) 1999 by American Society of Clinical Oncology.