Treatment and survival after lung resection for non-small cell lung cancer in patients with microscopic residual disease at the bronchial stump.

OBJECTIVE

The aim of this study is a retrospective evaluation of survival in patients who had undergone lung resection for non-small cell lung cancer and in whose microscopic residual disease at the bronchial resection margin was found, according to the type of infiltration, histology, lymph node involvement and postoperative treatment.

METHODS

A total of 1384 patients underwent lung resection for non-small cell lung cancer at the Thoracic Surgery Unit of the University of Siena from 1983 through 1998. All patients underwent complete mediastinal lymphadenectomy and this guaranteed an accurate stadiation. Staging was done according to the TNM and UICC classifications. Residual microscopic disease at the bronchial resection margin was divided in mucosal microscopic residual disease and extramucosal microscopic residual disease. Patients dying within 30 days from operation were excluded from survival analyses. Survival was analysed by the product limit method of Kaplan and Meier and curves were compared using the log-rank test.

RESULTS

Microscopic residual disease was found postoperatively at the bronchial margin in 3.39% (47/1384), of all patients undergoing lung resection for non-small cell lung cancer. Thirty patients (2.16%) had extramucosal microscopic residual disease and 17 (1.22%) had mucosal microscopic residual disease. Seventeen patients received adjuvant radiotherapy after operation, two patients underwent completion pneumonectomy; no chemotherapy was given. Median survival for the whole group was 22 months. The probability of survival was not significantly (P > 0.05) correlated with the type of infiltration, nor with lymph node disease, neither with histology, although patients with squamous cell carcinoma had a median survival of 30 versus 12 months of patients with adenocarcinoma. The probability of survival could not be correlated with the administration of adjuvant radiotherapy.

CONCLUSIONS

A frozen-section analysis of the bronchial resection margin and peribronchial tissue should be made in all patients with endobronchial tumour. We suggest that patients with microscopic residual tumour and stage I or II disease should undergo re-operation, if possible. In patients with documented N2 disease we don't recommend re-operation; extending the magnitude of the resection is unlikely to alter their outcome. Choice treatment for these patients is radiotherapy.