Background The aim of this study is to report the experience with conversion surgery from six Gruppo Italiano Ricerca Cancro Gastrico (GIRCG) centers, focusing our analysis on factors affecting survival and the risk of recurrence. Methods A retrospective, multicenter cohort study was performed in patients who had undergone conversion gastrectomy between 2005 and 2017. Data were extracted from a GIRCG database including all metastatic gastric cancer patients submitted to surgery. Only stage IV unresectable tumors/metastases which became resectable after chemotherapy were included in this analysis. Results Forty-five resected M1 patients were included in the analysis. Reasons for being deemed unresectable at diagnosis were peritoneal involvement (PCI > 6) (n = 38, 84.4%), distant metastatic nodes (n = 3, 6.6%) and extensive liver involvement (n = 4, 8.8%). Median follow-up was 25 months (IQR 9-50). Median overall survival from surgery was 15 months and 1-, 3-and 5-year survivals were 57.2, 36.1 and 24%, respectively. Median progression-free survival was 12 months with 1-and 3-year survival of 46.4 and 33.9%, respectively. At cox regression analysis the only independent prognostic factor for OS was the presence of more than one type of metastasis (HR 4.41,, p = 0.002). A positive microscopic resection margin was the only risk factor for recurrence (HR 5.72, 95% CI 1.04-31.4, p = 0.045). Conclusions Unresectable stage IV GC patients could benefit from radical surgery after chemotherapy and achieve long survivals. The main prognostic factor for these patients was the presence of more than one type of extra-gastric metastatic involvement.

KT remains a clinical challenge for gastric cancer therapy. The extent of disease and feasibility of removal of the metastatic lesion must be carefully evaluated prior to surgery to define the patients group who could benefit most from a resection associated with perioperative treatments.

Our data suggest some clinical criteria that may facilitate selection of candidates to curative surgery, which offers the best survival chances, especially when associated with adjuvant chemotherapy.

Background Resection margin (RM) involvement is associated with negative prognosis after gastrectomy. Intraoperative frozen section (IFS) analysis allows radical resection to be achieved in a single operation but is timeconsuming and resource-consuming. The aim of this study was to assess risk factors associated with RM involvement to identify patients who would benefit from IFS analysis. Methods We retrospectively analyzed patients who underwent gastrectomy with curative intent for gastric or esophagogastric junction (EGJ) cancer from 2000 to 2014 in six Italian hospitals. RM status was assessed by IFS analysis and/or definitive histopathology examination. A set of 21 potential risk factors were compared in a multivariate analysis between patients with positive RMs on IFS analysis or definitive histopathology examination and a control cohort of similar patients with negative RMs, with the samples stratified into three subgroups (T1, T2-T4 Lauren intestinal pattern, T2-T4 Lauren diffuse/mixed pattern). Results One hundred forty-five patients had positive RMs. Survival was significantly worse in positive RM patients than in negative RM patients (89.5 months vs 28.9 months). Multivariate analysis showed that in T1 cancers a margin distance of less than 2 cm is a risk factor for RM involvement (odds ratio 15.7), in T2-T4 intestinal pattern cancers, serosa invasion (odds ratio 6.0), EGJ location (odds ratio 4.1), and a margin distance of less than 3 cm (odds ratio 4.0) are independent risk factors, and in T2-T4 diffuse/mixed pattern cancers, lymphatic infiltration (odds ratio 4.2), tumor diameter greater than 4 cm (odds ratio 3.5), EGJ location (odds ratio 2.8), and serosa invasion (odds ratio 2.2) are independent risk factors. Conclusions Survival after gastrectomy is negatively affected by positive RMs. IFS analysis should be routinely used in patients with a high risk of positive RMs, especially in diffuse pattern cancers.

Although PG for upper third GC showed good results in terms of survival, it is associated with an increased mortality rate and a higher risk of reflux esophagitis and anastomotic stricture.