Analysis of the T descriptors and other prognosis factors in pathologic stage I non-small cell lung cancer in China.

BACKGROUND

The seventh edition of the tumor, node, metastasis Classification of Malignant Tumors is due to be published in 2009. The recommendations of International Association for the Study of Lung Cancer for changes to the T descriptors have been published. We combined this new parameter with other well-established prognostic factors and performed multivariate survival analyses to validate its value in Chinese stage I non-small cell lung cancer (NSCLC).

METHODS

We try to validate the new staging project in 325 patients who underwent complete surgical resection for stage I NSCLC in Single Institution of Shanghai Chest Hospital from 1998 to 2003. Variables in the analysis included age, gender, performance status, history of smoking, pathologic type, type of resection (pneumonectomy, lobectomy, and bilobectomy), tumor size (greatest dimension of tumor), T-status (T1 or T2), type of lymph node resection (systematic mediastinal lymphadenectomy or mediastinal lymph node sampling), lymphovascular vessel invasion, and adjuvant chemotherapy.

RESULTS

The 5-year overall survival (OS) of patients whose tumor measured no larger than 2 cm in largest diameter or larger than 2 cm but no larger than 3 cm were 75.49 and 74.58%, respectively. For those with tumors measured larger than 3 cm but smaller than 5 cm or larger than 5 cm but smaller than 7 cm were 60.87 and 55.63%. The 5-year OS of patients whose tumor measured larger than 7 cm was 46.15% (p = 0.025). The 5-year disease-free survival rates of patients whose tumor measured no larger than 2 cm in largest diameter or larger than 2 cm but no larger than 3 cm were 67.65 and 66.67%, respectively. For those with tumors measured larger than 3 cm but smaller than 5 cm or larger than 5 cm but smaller than 7 cm were 53.14 and 52.63%. The 5-year disease-free survival rate of patients whose tumor measured larger than 7 cm was 30.77% (p = 0.009). Multivariate analyses revealed that age, gender, type of resection (pneumonectomy, lobectomy, and bilobectomy), tumor size (greatest dimension of tumor), type of lymph node resection (systematic mediastinal lymphadenectomy or mediastinal lymph node sampling), and lymphovascular vessel invasion were significant predictive factors for OS.

CONCLUSIONS

The tumor size is a significant independent prognostic factors in stage I NSCLC.