Time trends and survival after surgery for p-stage IIIa, pN2 non-small cell lung cancer (NSCLC)

To evaluate the role of surgery for p-stage IIIa, pN2 non-small cell lung cancer (NSCLC), time trends and survival after surgery and the prognostic factors were investigated retrospectively.

Consecutive patients, 155, with p-stage IIIa, pN2 NSCLC who underwent thoracotomy at the Department of Thoracic Surgery, Chest Disease Research Institute, Kyoto University between January 1976 and December 1990 were divided into three groups by the period of operation (the earlier period: 1976-1980, n = 49; the middle period: 1981-1985, n = 55; and the later period: 1986-1990, n = 51), and were reviewed. Of the 155 patients, 84 (54.2%) were preoperatively evaluated to have mediastinal lymph nodes metastases (cN2 disease).

The 5 year survival rates in the earlier, middle and later periods were 12.1, 18.6, and 43.8%, respectively, showing significant improvement in the later period (P < 0.001, for the later period versus the earlier period or the middle period). The improvement was caused by decrease in the rate of operation-related death (4.1, 1.8, and 0.0%, in the earlier, the middle, and the later period, respectively), increase in the rate of complete tumor resection (59.1, 76.4, and 96.1%, respectively), and decrease in the ratio of pT3N2M0 patients (44.9, 34.5, and 17.6%, respectively) having poor prognosis compared with pT1-2N2M0 patients. Decrease in the ratio of cT3N2M0 patients and for increase in the rate of complete resection could be realized by accurate preoperative diagnosis with introduction of chest computed tomography (CT). Based on the preoperative evaluation, the 5 year survival rates of cT1N2M0, cT2N2M0, and cT3N2M0 patients were 39.4, 30.5, and 10.2%, respectively, showing significant poor prognosis in cT3N2M0 patients.

In cT1-2N2M0 or pT1-2N2M0 patients, a good prognosis can be realized by complete tumor resection with mediastinal lymph nodes dissection. In contrast, surgical treatment should not be justified in cT3N2M0 or pT3N2M0 patients.