A O04 Prevalence and risk factors for malignant nodal involvement in early oesophago-gastric cancer: Initial results from the CONGRESS study (endosCopic resectiON, esophaGectomy or gastrectomy foR Early oeSophagogastric cancerS)

Abstract

Abstract Background Controversy remains surrounding the optimal management of patients with T1N0 early oesophago-gastric (OG) cancer. Current guidelines recommend consideration of radical surgery for T1b disease because of the greater risk of nodal metastasis. However, data to accurately predict risk for individual patients is sparse; individual units may see only low numbers of patients with early stage disease. The endosCopic resectiON, esophaGectomy or gastrectomy foR Early oeSophagogastric cancerS (CONGRESS) study was a retrospective multinational study which aimed to characterise the impact of different management strategies, including endoscopic resection (ER) and radical surgery, for early OG cancer on a large scale. Methods An international multicentre retrospective study was performed. Inclusion criteria were all patients diagnosed with T1N0 OG cancer from 2015 to 2022. Led by local and regional collaborators, centralised anonymised data capture was used to record diagnostic, demographic, treatment, and outcome data. Histopathological outcomes for surgical resection specimens were compared to pre-operative staging and diagnostic data. Statistical analysis was performed to assess the association between patient demographic and histological data, and presence of malignant nodal disease. Results A total of 1,509 patients from 26 centres were recorded, with a median 33 months (range 0-194) follow-up from diagnosis. Initial T stage at diagnosis was T0 266/1509 (17.6%), unspecified T1 375/1509 (24.9%), T1a 319/1509 (21.1%), T1b 204/1509 (13.5%), TX 313/1509 (20.7%). Of 436 patients who underwent surgical resection, the risk of nodal metastasis for each clinically or endoscopically staged depth of invasion was T0: 5/31 (16.1%), unspecified T1: 37/193 (19.2%), T1a: 7/73 (9.6%) T1b: 21/137 (15.3%). No histological or patient factors were significantly associated with presence of positive nodes in the surgical resection specimen. Conclusions The risk of nodal metastases in this real-world contemporary dataset suggests a higher rate of nodal metastasis than reported in some series. Tumour depth alone is a poor predictor of nodal positivity. Further work is required to determine which patients might benefit from an organ-preserving versus resective treatment approach.