Toshifumi Yamaguchi1,2, Atsuo Takashima3, Kengo Nagashima4, Masanori Terashima5, Masaki Aizawa6, Manabu Ohashi7, Ryo Tanaka8, Tatsuya Yamada9, Takahiro Kinoshita10, Hisayuki Matsushita11, Koshiro Ishiyama12, Kei Hosoda13, Yasuhiro Yuasa14, Shusuke Haruta15, Naoki Kakihara16, Kazuhiro Nishikawa17, Gen Yunome18, Taroh Satoh1, Takeo Fukagawa19, Hitoshi Katai20, Narikazu Boku2. 1. Department of Frontier Science for Cancer and Chemotherapy, Osaka University Graduate School of Medicine, Suita, Japan. 2. Division of Gastrointestinal Medical Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan. 3. Division of Gastrointestinal Medical Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan. atakashi@ncc.go.jp. 4. Research Center for Medical and Health Data Science, The Institute of Statistical Mathematics, Tokyo, Japan. 5. Division of Gastric Surgery, Shizuoka Cancer Center, Shizuoka, Japan. 6. Department of Gastroenterological Surgery, Niigata Cancer Center Hospital, Niigata, Japan. 7. Department of Gastroenterological Surgery, Cancer Institute Hospital, Tokyo, Japan. 8. Department of General and Gastroenterological Surgery, Osaka Medical College Hospital, Takatsuki, Japan. 9. Department of Gastroenterological Surgery, Saitama Cancer Center, Saitama, Japan. 10. Gastric Surgery Division, National Cancer Center Hospital East, Kashiwa, Japan. 11. Department of Surgery, Tochigi Cancer Center, Utsunomiya, Japan. 12. Department of Surgery, Yamagata Prefectural Central Hospital, Yamagata, Japan. 13. Department of Upper Gastrointestinal Surgery, Kitasato University School of Medicine, Tokyo, Japan. 14. Department of Gastroenterological Surgery, Tokushima Red Cross Hospital, Komatsu, Japan. 15. Department of Gastroenterological Surgery, Toranomon Hospital, Tokyo, Japan. 16. Department of Surgery, Japanese Red Cross Kyoto Daini Hospital, Kyoto, Japan. 17. Department of Surgery, National Hospital Organization Osaka National Hospital, Osaka, Japan. 18. Department of Surgery, Sendai Medical Center, Sendai, Japan. 19. Department of Surgery, Teikyo University School of Medicine, Tokyo, Japan. 20. Division of Gastric Surgery, National Cancer Center Hospital, Tokyo, Japan.
Abstract
BACKGROUND: Gastric cancer (GC) patients with peritoneal metastasis are defined as stage IV in the Japanese classification of GC. For patients with peritoneal metastasis limited to positive peritoneal lavage cytology (CY1) and/or localized peritoneal metastasis (P1a), gastrectomy followed by S1 monotherapy is one of the most widely accepted therapeutic strategy in Japan. This study investigated the efficacy of preoperative chemotherapy as initial treatment in GC patients with CY1 and/or P1a. METHODS: We retrospectively reviewed GC patients diagnosed with CY1 and/or P1a at 34 institutions in Japan between 2008 and 2012. Selection criteria were: adenocarcinoma, no distant metastasis except CY1 or P1a, and no prior treatment. The subjects were divided into an Initial-Chemotherapy group and an Initial-Surgery group, according to the initial treatment. RESULTS: A total of 824 patients were collected and 713 eligible patients were identified for this study. As the initial treatment, 150 patients received chemotherapy (Initial-Cx), and 563 patients underwent surgery (Initial-Sx). Initial-Cx regimens were cisplatin plus S1/docetaxel plus cisplatin plus S1/others (n = 90/37/23). Both overall survival (OS) and progression-free survival (PFS) were similar between the Initial-Cx and Initial-Sx groups (median OS 24.8 and 24.0 months, HR 1.07, 95% CI 0.87-1.3; median PFS 14.9 and 13.9 months, HR 1.04, 95% CI 0.85-1.27). The 5-year OS rates were 22.3% in the Initial-Cx group and 21.5% in the Initial-Sx group. CONCLUSIONS: Although, the preoperative chemotherapy did not show a survival benefit for GC patients with CY1 and/or P1a, initial-Cx showed favorable survival in patients who converted to P0 and CY0.
BACKGROUND: Gastric cancer (GC) patients with peritoneal metastasis are defined as stage IV in the Japanese classification of GC. For patients with peritoneal metastasis limited to positive peritoneal lavage cytology (CY1) and/or localized peritoneal metastasis (P1a), gastrectomy followed by S1 monotherapy is one of the most widely accepted therapeutic strategy in Japan. This study investigated the efficacy of preoperative chemotherapy as initial treatment in GC patients with CY1 and/or P1a. METHODS: We retrospectively reviewed GC patients diagnosed with CY1 and/or P1a at 34 institutions in Japan between 2008 and 2012. Selection criteria were: adenocarcinoma, no distant metastasis except CY1 or P1a, and no prior treatment. The subjects were divided into an Initial-Chemotherapy group and an Initial-Surgery group, according to the initial treatment. RESULTS: A total of 824 patients were collected and 713 eligible patients were identified for this study. As the initial treatment, 150 patients received chemotherapy (Initial-Cx), and 563 patients underwent surgery (Initial-Sx). Initial-Cx regimens were cisplatin plus S1/docetaxel plus cisplatin plus S1/others (n = 90/37/23). Both overall survival (OS) and progression-free survival (PFS) were similar between the Initial-Cx and Initial-Sx groups (median OS 24.8 and 24.0 months, HR 1.07, 95% CI 0.87-1.3; median PFS 14.9 and 13.9 months, HR 1.04, 95% CI 0.85-1.27). The 5-year OS rates were 22.3% in the Initial-Cx group and 21.5% in the Initial-Sx group. CONCLUSIONS: Although, the preoperative chemotherapy did not show a survival benefit for GC patients with CY1 and/or P1a, initial-Cx showed favorable survival in patients who converted to P0 and CY0.