Weight changes at diagnosis in solid tumours.

Abstract

e21655 Background: Unintentional weight loss is common in cancer and associated with increased morbidity and mortality. Most research to date has examined weight loss in advanced disease. The clinical significance of any weight change (WC) (loss/gain) before/at cancer diagnosis remains unclear. This study aimed to determine the prevalence and clinical significance of WC at diagnosis in out-patients with solid tumours presenting to a tertiary academic medical centre. Methods: A retrospective study of the electronic medical record (EMR) was conducted (n=6477). Those with a pre-diagnosis weight, T0, (recorded within 6 months of cancer diagnosis) and 2 subsequent weights (diagnosis, T1; final visit, T2) were identified (n=4258). Logistic regression and survival analysis identified WC predictors and overall survival respectively. The significance threshold was p < 0.05. Results: Mean age was 61 ±12.5 years. 54% (n=2315) were male. Common tumour sites were breast (17%; n=725), prostate (16%; n=664), lung (14%; n=599) and upper GI (11%; n=470). Known metastatic disease present at T1=15% (n=652). 68% (n=2908) were overweight or obese (WHO BMI Classification) at T1. 98% (n=4159) had WC from T0-T1(loss: 58%; n=2454; gain: 40%; n=1705). Primary tumour sites significantly associated with weight loss (WL) included colon, head & neck, kidney, lung and upper GI. 8% (n=320) were cachectic (>5% WL in previous 6 months) and 50% (n=2134) were pre-cachectic (≤ 5% WL) at T1; 3% had “Abnormal Weight Loss” (ICD 9 Code). Survival was worst with WL >5% and weight gain (WG) ≥ 10% from T0-T1 (p<0.05). However, those with 2.5-5% WL from T0-T1 were also at risk (p<0.05); 0.1-2.4% WG was protective. Primary tumour site (lung, upper GI) and normal/underweight BMI at T1 predicted poor prognosis. Conclusions: Weight changes were highly prevalent, but WL typically was undiagnosed. Most were overweight or obese at diagnosis. Nevertheless 58% (n=2454) of those reviewed at T1 met current criteria for cachexia or pre-cachexia. Those with WL > 5% or WG ≥ 10% had worst survival. The majority had evidence of significant, yet frequently undiagnosed, WC abnormalities at diagnosis.