The pattern of lymph node metastasis and the suitability of 7th UICC N stage in predicting prognosis of remnant gastric cancer

Abstract

The original disease and previous operation usually cause abnormal lymphatic drainage of remnant gastric cancer (RGC). We analyzed metastatic lymph nodes (MLNs) of RGCs to explore the pattern of lymphatic metastasis and rational surgical treatment for RGC. Eighty-three RGC patients who underwent radical gastrectomy from July 1991 to July 2008 enrolled in this retrospective analysis. Original disease, tumor size, Borrmann type, depth of invasion, and histological type were related to an increased risk of lymph node (LN) metastasis (P < 0.05). Multivariate logistic analysis revealed that tumor size and depth of invasion were independent predictive factors of LN metastasis (P < 0.05). In comparison with upper one-third gastric cancer, patients with RGC tended to have a lower incidence of perigastric LN metastasis and higher incidence of metastasis to the mesojejunum and lower mediastinal LNs. A high incidence of MLNs in the No. 14 and mesojejunum was found from the patients who had previously undergone Billroth II reconstruction, while patients after Billroth I reconstruction had higher No. 12 and No. 13 LN metastasis rates. Cut-point survival analysis demonstrated that the most appropriate cutoffs of MLNs were set at 0, 2, 6, and 9. Patients of 0, 1–2, 3–6, 7–9, or ≥10 MLNs presented with median survival time of 37, 35, 24, 13, and 9 month, respectively. Preoperative diagnosis of depth of invasion and tumor size can help surgeons to evaluate LN metastasis. The 7th UICC N stage may be unsuitable and should be evaluated and improved in order to help surgeons rationally to estimate N stage of RGC.