Natural killer cells over time in patients with colorectal cancer

The purposes of the investigation were: 1) to examine the natural killer (NK) cell levels in a homogeneous group of patients with cancer between the presurgical period and 6 months after surgery; 2) to identify changes in the number of NK cells over time; and 3) to determine whether an association exists among the number of NK cells, demographics, stage of cancer, and treatment variables.

A longitudinal descriptive design was used to study biopsychosocial factors in persons newly diagnosed with colorectal cancer over a 6-month period.

Patients without ostomies had a significant decrease in NK levels over time, whereas patients with ostomies had a significant increase in NK levels over time. There was a difference in NK level over time for patients who were receiving the additional therapy of radiation alone and a combination of radiation and chemotherapy from those patients who were not receiving additional therapy. Natural killer levels in patients who were receiving radiation alone or a combination of radiation and chemotherapy significantly declined over time, where NK levels in patients receiving no additional treatment significantly increased over time.

Patients with low NK levels should be monitored during the course of their illness and cancer treatment to determine the relationship to immune status of other variables such as nutritional status, infection rates, and functional status.