Abstract 2637: Impact of pre-diagnosis weight loss on outcomes in a prospective cohort of esophageal cancer patients

Background: Esophageal cancer survival rates remain extremely low and factors influencing outcomes for this malignancy are not well understood. Tumor cachexia is a poor prognostic factor for certain tumor types, but is not well-studied in esophageal cancer. Weight loss in esophageal cancer is likely multifactorial; it can be due to tumor cachexia as well as dysphagia from obstructing tumors. In this present study, we aimed to investigate the relationship between weight loss and overall survival in a cohort of esophageal cancer patients and to determine whether these associations differed with tumor size. Methods: We prospectively enrolled subjects with recently diagnosed esophageal cancer at two tertiary care centers. Using a baseline questionnaire, we assessed demographics, medical history, medication use, and lifestyle factors. We recorded self-reported height and weight one year prior to and at diagnosis, which we used to calculate body mass index (BMI) and percent weight change, categorized by tertile. We ascertained from the medical records tumor characteristics including T stage (T1/2 or T3/4), location, pathology, and metastasis status, and collected follow-up data on treatment, imaging, and death. We used Cox regression to assess the association between percent weight loss and all-cause mortality. Results: We included 134 subjects in the analyses, the majority of whom were male (81.3%) and had adenocarcinoma (82.1%). The median BMI one year prior to diagnosis was 28.3 (IQR 24.4 - 31.0) and median percent weight loss was 4.7% (IQR 0 - 10.9%). There was no association between BMI one year prior and all-cause mortality (HR 0.98, 95% CI 0.93 - 1.03). Increasing percent weight loss was associated with increased risk of all-cause mortality (unadjusted HR 2.74 for highest vs. lowest tertile, 95% CI 1.34 - 5.58, Ptrend = 0.005) and this remained significant when adjusted for BMI one year prior (HR 2.87 for highest vs. lowest tertile, 95% CI 1.40 - 5.89, Ptrend = 0.003). We found significant interaction between weight loss and T stage. Percent weight loss was significantly associated with all-cause mortality, adjusted for BMI one year prior, among patients with T stages 1 or 2 (HR 6.49 for highest vs. lowest tertile, 95% CI 1.30 - 32.4, Ptrend = 0.012), but not T stages 3 or 4 (HR 1.42 for highest vs. lowest tertile, 95% CI 0.54 - 3.71). In the final multivariable model, there remained a significant association between percent weight loss and all-cause mortality among patients with T stages 1 or 2 (HR 6.34 for highest vs. lowest tertile, 95% CI 1.22 - 33.1, Ptrend = 0.022). Conclusions: In this cohort of esophageal cancer patients, we found that pre-diagnosis weight loss was associated with increased risk of all-cause mortality in patients with earlier stage tumors, independent of baseline BMI. We suspect that weight loss in early stage esophageal cancer may be due to tumor cachexia, a potential marker of more aggressive disease and worse prognosis. Citation Format: Sherry Shen, James L. Araujo, Nasser K. Altorki, Joshua R. Sonett, Adriana Rodriguez, Kivilcim Sungur-Stasik, Alfred I. Neugut, Julian A. Abrams. Impact of pre-diagnosis weight loss on outcomes in a prospective cohort of esophageal cancer patients. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2637.