Monoclonal antibody KP16D3 as a prognostic marker in stage I lung adenocarcinoma

Monoclonal antibody KP16D3 recognizes a 60 kDa protein associated with mucin-nonproducing papillary adenocarcinoma, especially that originating from nonciliated bronchiolar epithelial cells of the lung. We immunohistochemically examined 56 primary lung adenocarcinomas using the monoclonal antibody KP16D3. Of these tumors, 31 (55%) were positive for KP16D3 immunoreactivity. The disease-free survival rates showed no statistical differences between KP16D3-positive and KP16D3-negative patients. However, in stage I and T1 disease, the disease-free survival rates of KP16D3-positive patients were statistically lower than those of KP16D3-negative patients (P < 0.05). These findings suggest that KP16D3 may be useful as a prognostic marker for patients with stage I primary lung adenocarcinoma. Conversely, use of this marker and subtyping of lung adenocarcinomas reflect the prognosis of the disease.