Abstract: Objective: To evaluate the effect of regorafenib in combination with PD-1 inhibitor on survival rates, levels of diseaserelated
factors, and adverse reactions in patients with advanced rectal cancer. Methods: Eighty patients with advanced rectal cancer
admitted to the First Affiliated Hospital of Bengbu Medical University from January 2019 to December 2020 were selected and divided
into the experimental group （regorafenib combined with PD-1 inhibitor, 40 cases） and the control group （regorafenib monotherapy, 40
cases） by the random number table method. The primary observed indicators include treatment efficacy, levels of disease-related factors
（fatty acid synthetase （FAS）, tumor M2-type pyruvate kinase （TuM2-PK）, epidermal growth factor （EGF）, interleukin-17 （IL-17）,
insulin-like growth factor 1 （IGF-1）, tumor necrosis factor α （TNF-α））, survival rates, and incidence of adverse reactions. Results:
The objective response rate of patients in the experimental group was significantly higher than that in the control group （P<0.05）. After
treatment, the levels of FAS, TuM2-PK, EGF, IL-17, IGF-1 and TNF-α in both groups were significantly decreased（ P<0.05）, and the
levels of various disease-related factors in the experimental group were significantly higher than those in the control group （P<0.05）.
The survival rates of patients in the experimental group at 1 year and 2 years after treatment were significantly higher than those in the
control group （P<0.05）, and the 3-year survival rate was higher than that in the control group, but the difference was not statistically
significant（ P>0.05）. The main adverse reactions of patients in both groups included gastrointestinal symptoms, abnormal liver function,
abnormal renal function, skin reactions and bleeding risk. There was no statistically significant difference in the incidence of each
adverse reaction （P>0.05）. Conclusion: Regorafenib in combination with PD-1 inhibitor significantly improves the objective response
rate and survival rates, reduces levels of disease-related factors, and does not increase the incidence of adverse reactions in patients
with advanced rectal cancer, showing good clinical application prospects.

Key words: regorafenib, PD-1 inhibitor, advanced rectal cancer, survival rate, disease-related factors, adverse reactions