title: Does remnant gastric cancer really differ from primary gastric cancer? A systematic review of the literature by the Task Force of Japanese Gastric Cancer Association.
abstract: Remnant gastric cancer, most frequently defined as cancer detected in the remnant stomach after distal gastrectomy for benign disease and those cases after surgery of gastric cancer at least 5 years after the primary surgery, is often reported as a tumor with poor prognosis. The Task Force of Japanese Gastric Cancer Association for Research Promotion evaluated the clinical impact of remnant gastric cancer by systematically reviewing publications focusing on molecular carcinogenesis, lymph node status, patient survival, and surgical complications. A systematic literature search was performed using PubMed/MEDLINE with the keywords "remnant," "stomach," and "cancer," revealing 1154 relevant reports published up to the end of December 2014. The mean interval between the initial surgery and the diagnosis of remnant gastric cancer ranged from 10 to 30 years. The incidence of lymph node metastases at the splenic hilum for remnant gastric cancer is not significantly higher than that for primary proximal gastric cancer. Lymph node involvement in the jejunal mesentery is a phenomenon peculiar to remnant gastric cancer after Billroth II reconstruction. Prognosis and postoperative morbidity and mortality rates seem to be comparable to those for primary proximal gastric cancer. The crude 5-year mortality for remnant gastric cancer was 1.08 times higher than that for primary proximal gastric cancer, but this difference was not statistically significant. In conclusion, although no prospective cohort study has yet evaluated the clinical significance of remnant gastric cancer, our literature review suggests that remnant gastric cancer does not adversely affect patient prognosis and postoperative course.
authors.affiliation: Department of Surgery, Toho University School of Medicine, Tokyo, Japan. hideaki.shimada@med.toho-u.ac.jp.|Society of Japanese Gastric Cancer Task Force for Research Promotion, Tokyo, Japan. hideaki.shimada@med.toho-u.ac.jp.
authors.forename: Hideaki
authors.initials: H
authors.lastname: Shimada
authors.affiliation: Gastric Surgery Division, National Cancer Center Hospital, Tokyo, Japan.
authors.forename: Takeo
authors.initials: T
authors.lastname: Fukagawa
authors.affiliation: Department of Surgery, National Hospital Organization Kumamoto Medical Center, Kumamoto, Japan.|Department of International Medical Cooperation, Graduate School of Medical Sciences Kumamoto University, Kumamoto, Japan.
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Haga
authors.affiliation: Department of Biostatistics, School of Public Health, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.|Interfaculty Initiative in Information Studies, Graduate School of Interdisciplinary Information Studies, The University of Tokyo, Tokyo, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Oba
mesh_terms: D005743:Gastrectomy / Q000009:adverse effects / Q000401:mortality; D018530:Gastric Stump / Q000473:pathology* / Q000601:surgery; D006801:Humans; D008207:Lymphatic Metastasis / Q000473:pathology; D011379:Prognosis; D013274:Stomach Neoplasms / Q000401:mortality* / Q000473:pathology* / Q000601:surgery
keywords: Carcinogenesis; Lymph node; Prognosis; Remnant gastric cancer; Systematic review