Background: Clinical stage I pulmonary adenocarcinoma (AD) patients with persistently high serum carcinoembryonic antigen (CEA) levels after surgery have a poor prognosis. Although CEA staining pattern is reported to be a prognostic indicator for patients with colorectal cancer, the relationship with lung cancer is unclear.
Methods: One hundred eighteen patients with clinical stage I AD underwent surgery from 1993 to 1997. Of them, 19 (16%) patients with a high preoperative serum level of CEA and 19 randomly selected control patients with preoperatively normal CEA were studied. CEA staining of tumor specimens from each of the 38 patients was performed, and the staining patterns were then classified into two types: apical and diffuse.
Results: Patients with normal postoperative serum CEA levels (group HN, n = 13) had a 5-year survival rate higher than those with persistently high postoperative serum CEA (group HH, n = 6). In a comparison between the two groups, apical patterns (n = 10) were only seen in group HN, and those who demonstrated an apical CEA staining pattern had a 5-year survival rate (5-YSR) of 80% as compared with 13% for those HN patients with only a diffuse pattern (p = 0.01). In the control group, 16 (84%) patients had an apical staining pattern and the other 3 patients showed no staining.
Conclusions: Patients with normalized serum CEA levels had a high chance of showing an apical staining pattern, which may be a very good prognosis predictor for patients with high preoperative levels of CEA.