To observe the clinical efficacy and safety of programmed death-1 (PD-1) inhibitors (tislelizumab injection or sintilimab injection) combined with the capecitabine tablet and oxaliplatin for injection regimen (XELOX) as first-line treatment in patients with advanced gastric signet-ring cell carcinoma (SRCC)

Patients with SRCC were enrolled and divided into control group and treatment group using a random number table. The control group received the XELOX regimen, 130 mg·m^-2 intravenous oxaliplatin for injection on day 1, and oral 1 000 mg·m^-2 capecitabine tablets twice daily from days 1 to 14, repeated every 21 days. The treatment group received an intravenous infusion of tislelizumab injection or sintilimab injection 200 mg per dose prior to the XELOX regimen, also administered every 21 days. Both groups were treated for 6 cycles. Clinical efficacy, tumor markers, immune function, clinical scores, safety and long-term prognosis were compared between the two groups.

A total of 82 patients were included, with 41 cases in each group. The levels of carcinoembryonic antigen (CEA) in treatment and control group were (6.46±1.03) and (7.00±0.94) ng·mL^-1, respectively; the levels of carbohydrate antigen 19-9 (CA19-9) were (18.62±3.36) and (20.58±3.52) U·mL^-1, respectively; vascular endothelial growth factor (VEGF) were (33.57±5.56) and (36.15±5.03) ng·mL^-1, respectively; CD3⁺ T cells were (62.31±5.71)% and (59.50±6.10)%, respectively; CD4⁺ T cells were (47.56±5.93)% and (44.91±4.84)%, respectively; European organisation for research and treatment of cancer quality of life questionnaire core 30 (QLQ-C30) score were (60.15±11.01) and (55.02±9.46) points, respectively; and revised piper fatigue scale (RPFS) score were (5.05±0.89) and (5.49±0.84) points, respectively; the levels of CA72-4 were (34.07±3.74) and (36.23±3.01) U·mL^-1, respectively; the CD4⁺/CD8⁺ ratios were 1.99±0.35 and 1.75±0.37, respectively; the differences of above indicators between two groups were all statistically significant (P<0.05, P<0.01). Adverse drug reactions in both groups were gradeⅠorⅡand resolved after drug discontinuation. The incidence of adrenal dysfunction in the treatment group was 14.63% (6 cases/41 cases), which was significantly higher than that in the control group (0%) (P<0.05). The median survival time was 38 months in the treatment group and 28 months in the control group (P<0.05).

PD-1 inhibitors (tislelizumab or sintilimab injection) combined with the XELOX regimen as first-line therapy can enhance the efficacy in patients with advanced SRCC, significantly improve quality of life and long-term survival benefits, and exhibit a favorable safety profile. This therapeutic advantage may be attributed to the regimen’s effect on downregulating tumor markers and improving immune function.