Kohei Takizawa1, Hiroyuki Ono2, Yorimasa Yamamoto3, Hitoshi Katai4, Shinichiro Hori5, Tomonori Yano6, Eiji Umegaki7, Shunya Sasaki8, Toshiro Iizuka9, Kei Kawagoe10, Tadakazu Shimoda11, Manabu Muto12, Mitsuru Sasako13. 1. Division of Endoscopy, Shizuoka Cancer Center, 1007 Shimonagakubo, Nagaizumicho, Suntougun, Shizuoka, 411-8777, Japan. k.takizawa@scchr.jp. 2. Division of Endoscopy, Shizuoka Cancer Center, 1007 Shimonagakubo, Nagaizumicho, Suntougun, Shizuoka, 411-8777, Japan. 3. Department of Gastroenterology, Cancer Institute Hospital of the Japanese Foundation for Cancer Research, Tokyo, Japan. 4. Gastric Surgery Division, National Cancer Center Hospital, Tokyo, Japan. 5. Department of Endoscopy, National Hospital Organization Shikoku Cancer Center, Ehime, Japan. 6. Endoscopy Division, Department of Gastroenterology, National Cancer Center Hospital East, Kashiwa, Japan. 7. The Second Department of Internal Medicine, Osaka Medical College, Osaka, Japan. 8. Internal Medicine, Niigata Cancer Center Hospital, Niigata, Japan. 9. Department of Gastroenterology, Toranomon Hospital, Tokyo, Japan. 10. Department of Gastroenterology, Yamagata Prefectural Central Hospital, Yamagata, Japan. 11. Division of Pathology, Shizuoka Cancer Center, Shizuoka, Japan. 12. Department of Gastroenterology and Hepatology, Graduate School of Medicine, Kyoto University, Kyoto, Japan. 13. Department of Upper Gastrointestinal Surgery, Hyogo College of Medicine, Hyogo, Japan.
Abstract
BACKGROUND: Intramucosal gastric cancer, ≤3 cm (≤30 mm) with ulceration, and mixed histology (predominantly differentiated), was previously considered curative after endoscopic resection, and additional surgery was thought to be unnecessary. However, as the evidence base for these criteria remains insufficient, the Japanese Gastric Cancer Treatment Guidelines, ver. 3 (2010) specify that this pathology should be considered noncurative and recommend additional surgery. We report the frequency of lymph node metastasis in patients with these conditions based on a multicenter study. METHODS: Of patients with early gastric cancer who underwent gastrectomy with lymph node dissection, those with a mixed, predominantly differentiated tumor type, ulceration, a tumor diameter ≤3 cm, and no lymphovascular invasion were entered into this study. RESULTS: Four hundred and seven patients met the criteria, 21 of whom were excluded owing to a lack of available information. Thus, a total of 386 patients were included in the analysis, from 37 of the 42 member institutions. The mean study duration was 125 months. The most common combination of mixed histology was tub2 + por (67 %). None of the 386 patients had lymph node metastasis (95 % confidence interval, 0-0.8 %). CONCLUSION: The results of this retrospective study indicate that the risk of lymph node metastasis was less than 1 % among patients with the criteria defined here, considered to be criteria for noncurative resection as per the current guidelines, and suggest that observation alone without additional surgery may result in a good outcome.
BACKGROUND:Intramucosal gastric cancer, ≤3 cm (≤30 mm) with ulceration, and mixed histology (predominantly differentiated), was previously considered curative after endoscopic resection, and additional surgery was thought to be unnecessary. However, as the evidence base for these criteria remains insufficient, the Japanese Gastric Cancer Treatment Guidelines, ver. 3 (2010) specify that this pathology should be considered noncurative and recommend additional surgery. We report the frequency of lymph node metastasis in patients with these conditions based on a multicenter study. METHODS: Of patients with early gastric cancer who underwent gastrectomy with lymph node dissection, those with a mixed, predominantly differentiated tumor type, ulceration, a tumor diameter ≤3 cm, and no lymphovascular invasion were entered into this study. RESULTS: Four hundred and seven patients met the criteria, 21 of whom were excluded owing to a lack of available information. Thus, a total of 386 patients were included in the analysis, from 37 of the 42 member institutions. The mean study duration was 125 months. The most common combination of mixed histology was tub2 + por (67 %). None of the 386 patients had lymph node metastasis (95 % confidence interval, 0-0.8 %). CONCLUSION: The results of this retrospective study indicate that the risk of lymph node metastasis was less than 1 % among patients with the criteria defined here, considered to be criteria for noncurative resection as per the current guidelines, and suggest that observation alone without additional surgery may result in a good outcome.