Supplementary Tables from Circulating Tumor DNA Sequencing Analysis of Gastroesophageal Adenocarcinoma

Supplemental Table S1. Description of cohorts and sub-cohorts utilized in this study. Supplemental Table S2. Clinical information detailing patients in the "Baseline-cohort" ie untreated stage IV patients from UC and SMC who underwent ctDNA-NGS testing (n=144). Supplemental Table S3. Peri-operative ctDNA samples and their timing relative to surgery, DFS, maxVAF at the time of draw, and staging. Supplemental Table S4. Alterations detected in ctDNA in post-operative patients within 180 days of surgery. Supplemental Table S5. Frequencies of A) genomic alterations, B) mutations, or C) amplifications in initial tests across the entire Global GEA (n=1627) and UC/SMC subsets as seen in Figure 3. D) GA frequencies in genes common to ctDNA-NGS, MSK-Impact, and TCGA reported as percentage altered. Supplemental Table S6. Frequencies of GAs across the "Global-cohort" and UC/SMC subsets when narrowing patients from figure 3A to A) only initial tests with detectable non-synonymous alterations (n=1329) or B) only initial tests with maxVAF>0.5% (n=936), as seen in figure S3A-B. Similarly, initial tests from the "Global-cohort" were compared with MSK-Impact and TCGA using C) only ctDNA-NGS cases with non-synonymous alterations and D) ctDNA-NGS cases with maxVAF>0.5%. Supplemental Table S7. Detailed molecular information regarding clinically HER2-positive patient cohort (n=58). Supplemental Table S8. Alterations present upon progression of disease after 1L HER2-targeted therapy in patients with persistent HER2 amplification. Supplemental Table S9. Prognostic significance of alterations, mutations, and amplifications in potentially actionable genes.