Esophageal squamous cell carcinoma: Mortality-to-incidence ratio (MIR) and survival trends.

Abstract

e16135 Background: The most prevalent esophageal cancer globally is esophageal squamous cell carcinoma (ESCC). In the US, 90% of cases are linked to smoking, alcohol use, and diets low in fruits/vegetables. Most esophageal SCCs occur in the mid-esophagus and arise from polypoid excrescences, denuded epithelium, or plaques. Despite evidence of increasing esophageal cancer incidence in the US over 40 years, data on long-term survival trends and the impact of modern therapies remain limited. Methods: ESCC cases were extracted from the Surveillance, Epidemiology and End Result database Research Plus Data, 17 Registries, Nov 2023 Sub (2000-2021), using the ICD Code 8070/3 for squamous cell carcinoma, and C15 for esophagus. Data was stratified based on year of diagnosis (YOD), age, gender, race, stage, nodal spread, median household income inflation-adjusted to 2022, and treatment types. Analysis was performed using the Log-Rank test (GraphPad Prism). Results: A total of 23,684 cases of ESCC were identified. The median age of diagnosis was 68 years, with men accounting for 63.9% of the cases. Over 91% had positive lymph nodes. Racial distribution was observed as: White (57.6%), Black (22.8%), Hispanic (8.6%), Asian/Pacific Islander (10.1%), American Indian/Alaskan, and unknown race (< 1%) each. 5-yearly Mortality-to-Incidence Ratio (MIR) was calculated as 97.2% for 2000-2005, 94.1% for 2006-2010, 89.3% for 2011-2015, and 66.9% for 2016-2021 (p < 0.0001, Log-Rank test for trend). Overall median of survival (OS) was 9 months, with 1-year OS of 0.398 (CI 95%, 0.404-0.392), 3-year OS of 0.194 (CI 95%, 0.189-0.199), and 5-year OS of 0.14 (CI 95%, 0.145-0.135). MoS was significant for: Age (0-50 years, 10; 50+ years, 9; p < 0.0001), Gender (males, 8; females, 10; p < 0.0001), Race: (White, 9; Black, 7; Hispanics, 9; Asian/PI, 10; AI/Alaskans, 7; Unknown race, 5; p < 0.0001), Stage (localized, 15 months; regional, 13; distant, 5; unknown, 7; p < 0.0001), Lymph node(LN) spread (LN+, 8; LN-, 37; p < 0.0001), Income:(less than 100,000$, 8; over 100K, 11; p < 0.0001). Survival analysis based on different treatment modalities showed: surgery (29) vs no surgery (7) (p < 0.0001), chemotherapy (13) vs no chemotherapy (3) (p < 0.0001), and radiotherapy (13) vs no radiotherapy (4) (p < 0.0001). Conclusions: 23,684 cases of ESCC from the SEER database were analyzed. It predominantly affects the elderly, males, and Caucasians. Our study revealed a declining trend in the 5-year MIR from 2000 to 2021, likely due to earlier diagnoses and improved therapeutic strategies. Superior survival outcomes were associated with younger age, female sex, Asian/PI origin, localized disease, lack of nodal metastasis, income over 100K, and treatment with either surgery (highest outcome), chemotherapy, or radiation therapy.