Association between Foxp3 Tumor Infiltrating Lymphocyte Expression and Response After Chemoradiation in Nasopharyngeal Carcinoma

Abstract

BACKGROUND: Nasopharyngeal carcinoma (NPC) is a carcinoma originating from the surface epithelium of the nasopharynx with the highest incidence in China and South East Asia. Currently, many researchers are developing tumor microenvironment which can be assessed by tumor-infiltrating lymphochyte, and its association with treatment response in several tumors, including NPC. Foxp3, known as a regulatory T cell (Treg) marker, plays a role in the immunoregulatory environment of tumor cells and can be used as a prognostic factor. The relationship between Foxp3 expression and treatment response is considered as one of the factors affecting the prognosis of NPC. AIM: This study aims to determine the relationship between Foxp3 expression and treatment response in NPC. MATERIALS AND METHODS: A cross-sectional study was done to analyze the association between Foxp3 and treatment response in NPC. This study included 60 samples who were diagnosed with non-keratinizing NPC at the Department of Anatomical Pathology, Faculty of Medicine Universitas Indonesia/Cipto Mangunkusumo Hospital from January 2018 until December 2020. Immunohistochemistry was done to evaluate the expression of Foxp3. Foxp3 expression was evaluated in the intratumoral and peritumoral areas. RESULTS: Among 60 patients, the number of males were more than females (66.7%, 33.3%, respectively) with a ratio of 2:1. There was statistically significant difference between intratumoral and total Foxp3 expression and treatment response (p < 0.05, p = 0.001, respectively); however, no significant differences found between peritumoral Foxp3 expression and treatment response (p = 0.114). CONCLUSION: Foxp3 expression had a statistically significant relationship with response therapy after chemoradiation.