Objective: Nutritional status in cancer has been mostly biased toward undernutrition, an issue now in dispute. We aimed to characterize nutrition status, to analyze associations between nutritional and clinical/cancer-related variables, and to quantify the relative weights of nutritional and cancer-related features.
Methods: The cross-sectional study included 450 nonselected cancer patients (ages 18-95 years) at referral for radiotherapy. Nutritional status assessment included recent weight changes, body mass index (BMI) categorized by World Health Organization's age/sex criteria, and Patient-Generated Subjective Global Assessment (PG-SGA; validated/specific for oncology).
Results: BMI identified 63% as >or=25 kg/m(2) (43% overweight, 20% obese) and 4% as undernourished. PG-SGA identified 29% as undernourished and 71% as well nourished. Crossing both methods, among the 319 (71%) well-nourished patients according to PG-SGA, 75% were overweight/obese and only 25% were well nourished according to BMI. Concordance between BMI and PG-SGA was evaluated and consistency was confirmed. More aggressive/advanced stage cancers were more prevalent in deficient and excessive nutritional status: in 83% (n = 235/282) of overweight/obese patients by BMI and in 85% (n = 111/131) of undernourished patients by PG-SGA. Results required adjustment for diagnoses: greater histological aggressiveness was found in overweight/obese prostate and breast cancer; undernutrition was associated with aggressive lung, colorectal, head-neck, stomach, and esophageal cancers (p < .005). Estimates of effect size revealed that overweight/obesity was associated with advanced stage (24%), aggressive breast (10%), and prostate (9%) cancers, whereas undernutrition was associated with more aggressive lung (6%), colorectal (6%), and head-neck (6%) cancers; in both instances, age and longer disease duration were of significance.
Conclusion: Undernutrition and overweight/obesity have distinct implications and bear a negative prognosis in cancer. This study provides novel data on the prevalence of overweight/obesity and undernutrition in cancer patients and their potential role in cancer histological behavior.