Immunological changes and recovery-related factors in older patients with colon cancer: A pilot trial

Immunity in older patients with colon cancer differs from that in younger patients. Specifically, concerns regarding postoperative recovery and immunity have prompted the development of personalized treatment options for older patients with colon cancer. This study aimed to assess the differences in immunological factor-related parameters and postoperative recovery between patients aged ≥70 years and < 70 years.

This pilot study included 75 patients who underwent surgical resection for colon cancer between September 2023 and February 2024 at Asan Medical Center, Seoul, Korea. Patients were divided into two age groups: ≥70 years and < 70 years. The clinicopathological features associated with recovery, and the association among recovery, immunological factors, and clinical characteristics were analyzed. The EuroQol-5 Dimensions-3 questionnaire scores, which reflect the subjective perspectives of patients, were also compared between the two groups.

There were 29 patients in the ≥70 years group and 46 patients in the <70 years group. The ≥70 years group exhibited significantly higher IL-6 levels than the <70 years group both preoperatively (6.71 vs. 4.27, P = 0.04) and on postoperative day 21 (POD#21) (13.49 vs. 2.94, P = 0.03). The average NK cell counts were consistently higher in the ≥70 years group across all time points: preoperatively (24.54 vs. 13.87, P < 0.001), POD#3 (24.32 vs. 15.39, P < 0.001), and POD#21 (33.04 vs. 22.47, P < 0.001). While a greater proportion of patients in the ≥70 years group had below-average preoperative EQ-5D levels, this difference was not statistically significant (20.7 % vs. 17.4 %, P = 0.96).

Immunological factors, such as IL-6 levels and the number of natural killer cells, did not diminish in patients aged ≥70 years. Furthermore, postoperative recovery was not prolonged in this group.