7197 Background: To test the hypothesis that patients with completely resected p-stage I adenocarcinoma [Ad.] of the lung contain a favorable subgroup of patients with well differentiated histology and tumor 2.0 cm or less in greatest dimension, we analyzed the results of the JLCRG trial (a randomized prospective trial of adjuvant chemotherapy with Uracil-Tegaful for stage I adenocarcinoma of the lung) by tumor size, smoking history, degree of histological differentiation and more. Methods: Patients were randomized to receive either oral uracil-tegaful (250 mg of tegaful /m2/day) for 2 years postoperatively or no adjuvant treatment. Multivariate analyses and interactions with the Cox proportional-hazards model were used to estimate the simultaneous effects of prognostic factors on survival. Results: The 5-year survival rate of the 412 patients with tumor 2cm or less in size was 89.8% (95% confidence interval [CI]: 86.8 to 92.8) versus 84.4% (95% CI: 81.3–87.4) for the 569 patients with tumor more than 2cm in size (median follow-up 72 months, p = 0.002). Although univariate analysis demonstrated improved survival for the patients with no smoking history and female gender, the selected covariates by multivariate analysis were as follows: age (hazard ratio [HR] for patients aged 70 years or more, 2.25; 95% CI: 1.58 to 3.14, p < 0.0001), tumor size (HR for more than 2cm in size, 1.55; 95% CI: 1.10 to 2.21, p = 0.012), histological differentiation (HR for moderate and poor differentiation, 1.75, 95% CI: 1.25 to 2.47, p = 0.001), and treatment group (HR for the uracil-tegaful group, 0.68; 95% CI: 0.49 to 0.94, p = 0.02). For these prognostic factors, there was only one significant interaction between tumor size and the adjuvant treatment. Conclusions: 1) Patients with completely resected stage I Ad. of the lung contain a favorable subgroup of patients with aged less than 70 years, well differentiated histology, and a maximum tumor dimension of 2.0 cm or less. 2) Adjuvant chemotherapy with oral uracil-tegaful should also be considered for stage I Ad. patients more than 2 cm in tumor size. 3) 2cm in tumor size might be a good benchmark candidate of the description of T factor to facilitate treatment strategies and revisions of the TNM staging system. No significant financial relationships to disclose.
P8‐3: Gene amplification of ACTN4 is a predictive biomarker for the adjuvant chemotherapy with uracil‐tegafur in stage‐I patients with adenocarcinoma of the lung
