Effect of tumor size on prognosis in patients with non-small cell lung cancer: The role of segmentectomy as a type of lesser resection

Objective: As a result of increasing discovery of small-sized lung cancer in clinical practice, tumor size has come to be considered an important variable affecting planning of treatment. Nevertheless, there have been no reports including large numbers of patients and focusing on tumor size, and controversy remains concerning the surgical management of small-sized tumors. Therefore, we investigated the relationships between tumor dimension and clinical and follow-up data, as well as surgical procedure in particular. Methods: We reviewed the records of 1272 consecutive patients who underwent complete resection for non-small cell carcinoma of the lung. Results: Fifty patients had tumors of 10 mm or less, 273 had tumors of 11 to 20 mm, 368 had tumors of 21 to 30 mm, and 581 had tumors of greater than 30 mm in diameter. The cancer-specific 5-year survivals of patients in these 4 groups were 100%, 83.5%, 76.5%, and 57.9%, respectively. For patients with pathologic stage I disease, they were 100%, 92.6%, 84.1%, and 76.4%, respectively. Multivariate analysis demonstrated that male sex, older age, larger tumor, and advanced pathologic stage adversely affected survival. Lesser resection was performed in 167 (52%) of 323 patients with a tumor of 20 mm or less in diameter but in 156 (16%) of 949 patients with a tumor of greater than 20 mm in diameter. The percentages of lesser resection among all procedures performed were 79%, 56%, 30%, and 15% in patients with pathologic stage I disease with a tumor of 10 mm or less, 11 to 20 mm, 21 to 30 mm, and greater than 30 mm in diameter, respectively. The 5-year cancer-specific survivals of patients with pathologic stage I disease with tumors of 20 rum or less and 21 to 30 mm in diameter were 92.4% and 87.4% after lobectomy, 96.7% and 84.6% after segmentectomy, and 85.7% and 39.4% after wedge resection, respectively. On the other hand, with a tumor of greater than 30 mm in diameter, survivals were 81.3% after lobectomy, 62.9% after segmentectomy, and 0% after wedge resection, respectively. Conclusions: Tumor size is an independent and significant prognostic factor and important for planning of surgical treatment. Although lobectomy should be chosen for patients with a tumor of greater than 30 mm in diameter, further investigation is required for tumors of 21 to 30 mm in diameter. Segmentectomy should, as a lesser anatomic resection, be distinguished from wedge resection and might be acceptable for patients with a tumor of 20 mm or less in diameter without nodal involvement.