Associations of oxidative stress, metabolic disorders in colorectal cancer patients

Introduction
Colorectal cancer have been one of the most common malignant neoplasm in the world. In most patients with this cancer, we can observe both redox homeostasis and nutritional disorders.

Aim
To assess the occurrence of oxidative stress in patients with colorectal cancer and its severity depending on the nutritional status of patients.

Material and methods
The study group consisted of 50 patients with colorectal cancer. In the control group, samples were obtained from 40 healthy subjects. Basal metabolic index and nutrition risk screening (NRS) 2002 scale was completed. The total antioxidant capacity (TAC), total oxidant status (TOS), malondialdehyde (MDA) were determined yielding the oxidative stress index (OSI) determined by the TOS/TAC ratio and TAC/MDA ratio.

Results
There were statistically significant differences (p < 0.05) in the levels of not only TAC, TOS, OSI, but also MDA and TAC/MDA. In healthy patients, the TAC and TAC/MDA level was significantly higher (p < 0.05) compared to the cancer patients, while the TOS, OSI and MDA level was significantly lower (p < 0.05). In patients with BMI < 24.9 kg/m2, the level of TAC was significantly higher and the level of TOS was significantly lower (p < 0.05) compared to patients with BMI > 24.9 kg/m2. In patients with features of malnutrition according to the NRS 2002 scale, TOS and OSI were statistically significantly higher (p < 0.05).

Conclusions
Neoplastic disease, such as colorectal cancer, precipitates an increase in oxidative stress. Concurrently, the nutritional status of patients, especially malnutrition, further intensifies this process.