Years of Life Lost of Patients With Early Adenocarcinoma of the Esophagogastric Junction Compared to Esophageal or Gastric Adenocarcinoma. A Registry‐Based Study

OBJECTIVE: This registry-based study investigates patients with resected esophageal (EAC), cardiac (CAC), and gastric (GAC) pT1 adenocarcinoma (AC) concerning epidemiological, tumor-related, and prognostic factors, analyzing especially the impact on survival and years of life lost (YLL). BACKGROUND: As CAC is classified as esophageal cancer in the 7th and more specified in the 8th edition of the UICC-TNM classification, it remains unclear if significant differences exist for pT1 CAC in comparison to EAC and GAC. METHODS: We used the ICD-O-3 code comparing tumors in the esophagus (C15.0-C15.9), cardia (C16.0), and stomach (C16.1-C16.9). A total of 246,653 patients with these tumors were documented between 2010-2020 in the German Cancer Registry. Only ACs with histologically confirmed tumor infiltration into mucosa or submucosa (pT1) were included. YLL were calculated using life expectancy data from Germany. RESULTS: The study population consists of 9.442 patients with resected pT1 AC. Age and sex differed significantly between CAC (n = 1.870) and EAC (n = 2.018) as well as between CAC and GAC (n = 5.554). Tumor-related factors were significantly different between the three locations. Multivariate analysis showed significantly worse prognosis for CAC compared to the other locations. The median of YLL was 10.7 years for EAC, 8.5 years for CAC and 6.8 years for GAC (p < 0.0001). CONCLUSION: Patients with pT1 AC of the cardia differ from patients with EAC or GAC in terms of demographic, tumor-related factors, prognosis, and YLL. Therefore, separate classification of tumors originating in the cardia is useful. Future studies should investigate the influence of therapy on prognosis and YLL.