Should mediastinal nodal dissection be routinely undertaken in patients with peripheral small-sized (2 cm or less) lung cancer? Retrospective analysis of 225 patients

Objective: We retrospectively reviewed nodal status of the patients with peripheral small-sized lung cancer a grouped by cell type and tumor size to evaluate the necessity of systematic nodal dissection in this group of patients. Methods: From 1973 to 1998, 1713 patients underwent pulmonary resection for primary lung cancer in Kanazawa University. Among them, 225 patients (13.1%) with peripheral small-sized (2 cm or less) lung cancer underwent lobectomy and systematic nodal dissection were retrospectively reviewed. The maximum diameter of the tumor was measured on formalin-fixed surgical specimens. Results: The histological types were adenocarcinoma in 170 (75.6%), squamous cell carcinoma in 20 (8.9%), small cell carcinoma in 19 (8.4%) and others in 16 (7.1%). Among 170 adenocarcinoma patients, 38 (22.4%) showed hilar or mediastinal lymph node metastases. No mediastinal lymph node metastasis was encountered in all squamous cell carcinoma (n = 20), adenocarcinoma less than or equal to1 cm (n = 16), small cell carcinoma less than or equal to1 cm. (n = 4), and adenocarcinoma of Noguchi's classification type A or B (n = 24). Conclusions: Mediastinal nodal dissection would be unnecessary in the patients with peripheral small-sized lung cancer fulfilling these criteria: (1) squamous cell carcinoma less than or equal to 2 cm; (2) adenocareinoma less than or equal to 1 cm; (3) localized bronchioloalveolar carcinoma less than or equal to 2 cm without foci of active fibroblastic proliferation in histology (Noguchi's classification type A or B adenocarcinoma); (4) small cell carcinoma less than or equal to 1 cm. Candidates fulfilling above criteria were 28.4% (64/225) of small-sized lung cancer and 10.9% of stage IA patients. The establishment of a universally accepted therapeutic strategy for small-sized lung cancer is indispensable in the clinical spread of various sort of limited resections. (C) 2001 Elsevier Science B.V. All rights reserved.