Association between tumor mutation status, pretreatment weight change, and overall survival in metastatic non–small cell lung cancer.

Abstract

e24075 Background: Unintentional weight loss is common in non–small cell lung cancer (NSCLC) and has been correlated with poor outcomes. Additionally, tumor mutations may be associated with distinct metabolic changes. This study aimed to evaluate the association between tumor mutation status and pretreatment weight loss (WL) or weight gain (WG) in metastatic NSCLC. Additionally, the relationship between these weight changes and OS after treatment was examined. Methods: This is a retrospective (Jan 2017-Dec 2023) observational study of adults with new diagnosis Stage IV NSCLC treated at Atrium Health Levine Cancer (AHLC). Eligible patients had at least two recorded weight measurements, including a baseline weight and a follow-up weight measured closest to day 30 after diagnosis (±14 days). Patients with molecular testing (EGFR, ALK, ROS1, BRAF, KRAS) were identified. A Univariable and multivariable ordinal logistic regression were used to model tumor mutation status and impact on pretreatment weight changes. This was categorized into 3 groups: 1) WG/Stable, 2) WL <3%, and 3) WL ≥3%. OS was evaluated using direct adjustment methods. P<0.05 was statistically significant. Results are summarized by descriptive statistics, association level and survival analysis. Results: 264 patients were eligible. 218 patients had molecular testing results, (96/218) had a tumor mutation. Median age was 68 y/o; 48.6% female and 73.9% White. Demographic and clinical characteristics were similar between groups. However, the mutation group had higher proportion of females and current smokers. In multivariable models adjusting for age, sex, race, smoking status, obesity (BMI ≥30) Charlson Comorbidity Index, number of metastases and income/education, we found no significant association between pretreatment weight change and tumor mutation status. For the entire cohort (N=264), median OS from diagnosis was 22 (.43-.55) months. There was significant difference in OS between patients in different weight change groups (p=.042). Patients WG/Stable had the longest survival of 28 months (.41-.58) compared to those with ≥3% WL [18 (.38-.58) months, p=0.012], or <3% WL [22 (.41-.61) months, p=0.4]. Conclusions: Pre-treatment weight loss is an important prognostic indicator in metastatic NSCLC. A detailed weight history before treatment can help identify patients at high risk for early mortality and guide timely nutrition interventions. Pretreatment weight change and overall survival. Survival N 20 Months 40 Months 60 Months 80 Months Median, months # Deaths (%) Overall 264 53% (.48-.60) 34% (.28-.40) 21% (.14-.33) 14% (.07-.28) 22 159 (60%) Weight Change WG/Stable 109 60% (.52-.68) 40% (.32-.50) 26% (.17-.41) 18% (.09-.36) 28 64 (59%) <3% WL 80 55% (.46-.65) 35% (.26-.47) 22% (.12-.38) 14% (.06-.32) 22 48 (60%) ≥3% WL 75 44% (.35-.56) 24% (.17-.36) 13% (.06-.28) 8% (.03-.22) 18 47 (63%)