1 3 Int J Clin Oncol DOI 10.1007/s10147-015-0838-z ORIGINAL ARTICLE Gefitinib treatment in patients with postoperative recurrent non-small-cell lung cancer harboring epidermal growth factor receptor gene mutations Yuhei Yokoyama 1 · Makoto Sonobe 1 · Tetsu Yamada 1 · Masaaki Sato 1 · Toshi Menju 1 · Akihiro Aoyama 1 · Toshihiko Sato 1 · Fengshi Chen 1 · Mitsugu Omasa 1 · Hiroshi Date 1 Received: 3 February 2015 / Accepted: 28 April 2015 © Japan Society of Clinical Oncology 2015 and nonhematologic toxicities were generally mild, but 1 patient experienced interstitial lung disease. Conclusions Our results suggest that gefitinib treatment for recurrent lung cancer with gene EGFR mutations is a useful option in a practical setting, irrespective of the tim- ing of such treatment and the type of EGFR gene mutation present. Keywords Lung cancer · Epidermal growth factor receptor · Postoperative recurrence · Gefitinib Introduction Lung cancer is one of the major causes of death in many countries, including Japan. The most common type of lung cancer is non-small-cell lung cancer (NSCLC), and surgery is the mainstay of treatment for patients with resectable NSCLC [1]. However, tumor recurrence remains a major cause of postoperative death [2]. Recent advances in chem- otherapy, including molecularly targeted therapy, can facili- tate the long-term survival of recurrent or advanced lung cancer patients [3]. Tyrosine kinase inhibitors (TKIs) for epidermal growth factor receptor (EGFR) have been suc- cessful treatment options [4]. Following the identification of specific mutations in the tyrosine kinase domain of the EGFR gene within exons 18, 19, and 21 in most NSCLC patients who responded to EGFR-TKI [5, 6], several phase III clinical trials of EGFR-TKIs for recurrent or advanced NSCLC with EGFR gene mutations were conducted; those trials showed that EGFR-TKI provides better progression- free survival than conventional platinum-based chemother- apy [7–12]. It is worth noting, however, the patients enrolled on those clinical trials presented good performance status and Abstract Background The epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor gefitinib is an effective treatment for recurrent or advanced lung cancer harboring EGFR gene mutations, and has improved progression-free survival in several clinical trials. However, the effect of gefitinib treatment for recurrent lung cancers with EGFR gene mutations after complete resection and the influence of the timing of such treatment have not been fully eluci- dated in a practical setting. Methods We investigated 64 patients (median age: 68 years; men: 22; women: 42; adenocarcinoma: 61; aden- osquamous cell carcinoma: 2; combined large cell neu- roendocrine carcinoma: 1) with recurrent lung cancer after complete resection who received gefitinib for the recurrent lesions and in whom the tumors had EGFR gene mutations. Progression-free survival, response rate, and safety were analyzed. Results Complete response and partial response were achieved in 2 patients and in 42 patients, respectively (objective response rate: 69 %). Stable disease was obtained in 16 patients, the disease control rate was 94 %, and median progression-free survival was 16 months. The timing of gefitinib treatment (first line, second line, or later) and the type of EGFR gene mutation present did not influ- ence progression-free survival. However, a smaller num- ber of recurrent sites at the start of gefitinib treatment was linked to better progression-free survival. Hematologic * Makoto Sonobe mysonobe@kuhp.kyoto-u.ac.jp 1 Department of Thoracic Surgery, Kyoto University Hospital, Shogoin-Kawahara-cho 54, Sakyo-ku, Kyoto 606-8507, Japan