Risk of recurrence in patients with surgically resected stage I non-small cell lung carcinoma: histopathologic and immunohistochemical analysis.

STUDY OBJECTIVE

To evaluate the prognostic value of histopathologic variables and molecular markers in a group of patients with stage I non-small cell lung cancer (NSCLC).

SETTING

"María Ferrer" Hospital of Buenos Aires, Argentina.

PATIENTS

Pathologic stage IA and IB patients who underwent radical surgery and nonneoadjuvant therapy for NSCLC between January 1985 and December 1999.

MEASUREMENTS AND RESULTS

Fifty-three patients fulfilling the inclusion criteria were identified. The overall survival was 52.8%, and 28% of patients had recurrent disease. We found significant differences between squamous cell carcinoma (SCC) and adenocarcinoma in mitotic counting (p = 0.001) and lymphatic permeation (p = 0.01). SCCs showed higher proliferation (MIB-1 grades 2 and 3) [p = 0.001], Bcl-2 expression (p = 0.038), and CD44 expression (p = 0.019) than adenocarcinomas. The log-rank test showed that mitosis count, necrosis, MIB-1, and Bcl-2 were predictive factors for relapse. All of them were associated with increased relapse and a shorter time to recurrence. Multivariate analysis using the Cox proportional hazards regression model showed that mitosis count, Bcl-2 expression, and grade 3 of MIB-1 emerged as independent prognostic factors of recurrence.

CONCLUSIONS

We found that mitosis count and MIB-1 expression had significant value to predict recurrence, reflecting the aggressiveness of high-rate proliferative tumors. We could also show that patients with positive Bcl-2 tumors had a poor outcome, probably related to the uncontrolled cell growth that the expression of Bcl-2 promotes. Our observations are of potential interest for the development of rational postresection treatment strategies based on the estimated risk of recurrence of patients with NSCLC.