Outcomes of metastatic esophageal and gastroesophageal junction cancers: A 13-year single-center study.

e16061 Background: The prognosis of metastatic esophageal (Eso) and gastroesophageal (GEJ) cancers is poor. However, the introduction of immunotherapy and biologic agents has enhanced systemic treatment for these cancers. This study aims to explore survival outcomes of this patient population in a real-world setting. Methods: In this retrospective study, adults diagnosed with metastatic stage IVB esophageal (Eso) and gastroesophageal (GEJ) cancers, either squamous (SC) or adenocarcinoma (AC), treated at Cleveland Clinic from 1/2010-12/2022 were included. Patient with stages II-IVA, cervical Eso cancer, Siewert class 3 tumors and those who did not receive systemic therapy were excluded. Data obtained included demographics, clinical variables (ECOG, BMI, comorbidities), tumor stage, and treatment modalities. Treatment response was assessed using RECIST 1.1 criteria. Overall survival (OS) and progression-free survival (PFS) were calculated from date of therapy. Multivariable Cox proportional hazards (CPH) models examined the associations between covariates and survival outcomes. Results: Key baseline variables are summarized in Table 1. In the AC subtype (n = 322), median follow-up duration was 39 months, and 2-year OS was 19% (95% CI:15-23). Systemic therapy was used in all cases; FOLFOX or XELOX (n = 180, 56%), carboplatin + paclitaxel (n = 26, 8.1%), HER2 targeted therapy (n = 40, 12%) and immunotherapy ± chemotherapy (n = 30, 9.3%). Response rate was 51%. In a multivariable CPH model, those who received immunotherapy ± chemotherapy were shown to have significantly better OS and PFS compared to FOLFOX or XELOX alone (HR 0.50, 95%CI 0.30-0.83, P < 0.01) and (HR 0.54, 95%CI 0.34-0.86, P < 0.01), respectively. Additionally, ECOG 3 or 4 was associated with lower OS (P < 0.05). In the SC subtype (n = 37), median follow up was 26 months and 2-year OS was 22% (95% CI: 12-40). Majority of patients (n = 18, 49%) received systemic therapy + radiation (non-definitive). The rest received either systemic only (n = 14, 38%) or definitive chemoradiation (n = 5, 14%). Response rate was 51%. In a multivariable CPH model, those who received systemic therapy alone had decreased OS compared to those who received systemic therapy + radiation (HR 2.27, 95% CI 1.02-5.04, P < 0.05). No difference in PFS is present amongst the groups. Conclusions: In metastatic Eso and GEJ adenocarcinoma, IT ± chemotherapy was associated with improvement in PFS and OS compared to chemotherapy alone. This highlights the utility of immunotherapy in metastatic adenocarcinoma. In squamous cancer, chemotherapy + radiotherapy was associated with improved OS compared to systemic therapy alone, likely representing patients with oligo-metastatic disease. Baseline characteristics. AdenocarcinomaN = 322 Squamous CancerN = 37 Median Age (Q1,Q3) 64 (56,70) 65 (57,70) Male 288 (89%) 24 (65%) White 304 (95%) 27 (73%) Current/former smoker 215 (66%) 33 (89%)