To observe the changes of immune function, nutritional status, and performance status in patients after high-dose hypofractionated radiotherapy for pancreatic cancer.

We prospectively collected patients with pancreatic cancer who would undergo radiotherapy with helical tomotherapy at our hospital. A total dose of 50/60/70 Gy in 15 or 20 fractions was delivered to the PTV, CTV, and GTV, respectively. Lymphocyte percentage, humoral immunity indexes (IgG, IgA, IgM, C₃, and C₄), cellular immunity indexes (CD₃⁺, CD₄⁺, and CD₈⁺ T cells), nutrition related indexes (hemoglobin, albumin, and albumin to globulin ratio), and physical status (KPS) were evaluated before and after radiotherapy. The paired t-test was used to compare the difference in the immune indicators before and after treatment.

A total of 34 patients were enrolled in the study. The number of patients with a lower lymphocyte percentage than normal was 8 (23.5%) before treatment and 34 (100%) after treatment. The numbers of patients with lower IgG, IgA, IgM, C₃, and C₄ were 0, 0, 2 (5.9%), 7 (20.6%), and 1 (2.9%), respectively, before treatment; the corresponding numbers after treatment were 1 (2.9%), 0, 7 (20.6%), 6 (17.6%), and 0. The numbers of patients a lower CD₃⁺ T cell percentage, lower CD4⁺ T cell percentage, and higher CD₈⁺ T cell percentage were 1 (2.9%), 1 (2.9%), and 2 (5.9%), respectively, both before and after treatment. The lymphocyte percentage was decreased by 63.0±20.6% (P＜0.001) and IgM was decreased by 9.6±17.5% on average (P=0.011); the other parameters had no statistical difference before and after treatment. Before treatment, the numbers of cases with lower hemoglobin, albumin, and albumin to globulin ratio were 7 (20.6%), 4 (11.8%), and 0 (0) before treatment and 8 (23.5%), 4 (11.8%), and 0 (0) after treatment, respectively; there was no statistical difference in these paramters before and after treatment. After treatment, the KPS score was improved in 44.1% (15 cases) and stable in 44.1% (15 cases).

High-dose hypofractionated radiotherapy for pancreatic cancer has appreciated effect on the immune function of patients, but has little effect on the nutritional and performance status of patients.