Significance of Limited Resection for Small Peripheral Non-small-cell Lung Cancer : Multiinstitutional Prospective Study

目的.肺野末梢型小型非小細胞肺癌に対する縮小手術の意義を検討した.方法.1992年1月より1994年12月までに小型肺癌縮小手術Study Groupに登録された積極的適応群(腫瘍径2cm以下,NO)55例と,消極的適応群(腫瘍径,N規定無し)100例を対象とし,同時期に住友病院呼吸器外科および兵庫成人病センター呼吸器外科で手術が行われた腫瘍径2cm以下,NOの葉切例55例と比較した.結果.これら155例は全例手術後5年以上経過した.積極的適応群の他病死を除いた5生率は91.8%,消極的適応群中腫瘍径2cm以下,NO,拡大区域切除例の5生率は79.6%で,これらは同等と考えられ,両者を加えた群(以下拡大区域切除群)の5生率は89.5%で,葉切除群の5生率81.3%と差がなかった.拡大区域切除群の手術前後の肺機能変化は,FVCの減少率は11.3±9.8%で,葉切除群のFVC減少率18.3±11.2%に比し有意に少なかった.結論.肺野末梢型小型肺癌に対する拡大区域切除術は標準術式として妥当である.Objective. The usefulness of extended segmentectomy for small peripheral non-small-cell lung cancer was assessed by comparison with lobectomy. Study Design. From 1992 to 1994, 155 patients were enrolled in a multiinstitutional prospective trial for peripheral lung tumors. Fifty-five patients out of 155 were registered in the intended extended segmentectomy group and 100 patients who had preoperative complications were registered in the compromised group. In the extended segmentectomy group, the tumors were 2 cm or less in diameter and no metastatic lesion was detected by routine examinations. Twenty patients out of 100 who were enrolled in the compromised group had tumors smaller than 2 cm in diameter and NO disease. They received similar operations as patients in the intended extended segmentectomy group. Fifty-five patients in the intended extended segmentectomy group and 20 patients in the compromised group received extended segmentectomy, and these 75 patients were unified as the extended segmentectomy group. Fifty-five patients who received lobectomy in Sumitomo Hospital and Hyogo Medical Center for peripheral non-small-cell lung tumors 2 cm or less in diameter and no metastatic lesion were compared with the extended segmentectomy group. Result. There were 17 deaths in the extended segmentectomy group and 7 died due to lung cancer. In these 7 cancer-related deaths, 3 patients died due to lung tumors, 2 died due to distant metastases and 2 died as a result of local recurrence. In the lobectomy group, 19 patients died, 9 due to lung cancer. In these 9 patients, 2 died due to lung tumors, 4 died due to distant metastasis and 3 died due to local recurrence. Five-year survival rates of the extended segmentectomy group and the lobectomy group were 89.5% and 81.3%, respectively, and the difference was not statistically significant between these two groups. Postoperative reduction rates of FVC in the extended segmentectomy group and the lobectomy group were 11.3% and 18.3%, respectively, and the difference was statistically significant (p= 0.0046). Postoperative reduction rates of FEVi_ in the extended segmentectomy group and the lobectomy group were 13.4% and 16.0%, respectively, and no statistically significant difference was recognized (p= 0.247). Conclusion. Extended segmentectomy is a reasonable operation for small peripheral lung cancer