Effect of immune-modulating metronomic capecitabine as an adjuvant therapy in locoregionally advanced nasopharyngeal carcinoma

Abstract

Abstract Introduction Metronomic capecitabine used as an adjuvant therapy improves survival in patients with locoregionally advanced nasopharyngeal carcinoma (LA-NPC). This therapeutic approach may also contribute to improved immune function, consequently enhancing overall therapeutic efficacy. Aim We aimed to evaluate the effect of metronomic capecitabineas an adjuvant therapy on immune function and survival in cases of LA-NPC. Subjects and methods Enrolled in the study were 28 patients with LA-NPC, who were equally assigned to two groups of 14 each: experimental and control group. The experimental group received induction chemotherapy + concurrent chemotherapy + adjuvant chemotherapy as well as oral capecitabine at a dose of 650 mg/m² of body surface area twice daily for 1 year, with the option to discontinue in case of intolerance. The control group did not receive additional chemotherapy or targeted drugs after the induction chemotherapy + concurrent chemoradiotherapy; however, they were followed up regularly. Immune function changes and survival were compared between the two groups. Results The median follow-up time was 43.5 months. The experimental group exhibited higher levels of CD8+, CD28+, CD8+, and activated CD8+ cells 1 year after adjuvant chemotherapy compared to the control group (P < 0.05). The CD4/CD8 ratio and proportion of monocyte-derived dendritic cells of the experimental group were also higher than those of the control group, but the difference was not statistically significant (P ≥ 0.05). The comparisons of overall survival, local-regional recurrence-free survival, progression-free survival, and distant metastasis-free survival between the experimental group and the control group showed percentages of 92.9% vs. 78.6%, 92.9% vs. 92.9%, 78.6% vs. 71.4%, and 85.7% vs. 78.6%, respectively, but these differences were not significant (P > 0.05). Conclusion It was observed that metronomic capecitabine chemotherapy induces an immunomodulatory effect in LA-NPC. Trial registration: NCT02958111, date of registration 04-11-2016.