Abstract: Objective To investigate the clinical value of magnetic resonance imaging (MRI) texture analysis plus diffusion-weighted imaging (DWI) in predicting the response to radiotherapy and chemotherapy in nasopharyngeal carcinoma (NPC). 
Methods A total of 102 patients with NPC treated by radiotherapy and chemotherapy in the First People′s Hospital of Lianyungang City from July 2020 to August 2023 were selected. MRI texture analysis and DWI scanning were performed before radiotherapy and chemotherapy. They were divided into good response group (n=46) and poor response group (n=56) according to the response to radiotherapy and chemotherapy. Baseline data, MRI texture analysis and DWI scanning results of the two groups were recorded to analyze the correlation of MRI texture analysis and DWI scanning results with the response to radiotherapy and chemotherapy for NPC, and to analyze the impact of MRI texture analysis and DWI scanning results on the response to radiotherapy and chemotherapy and predictive value for NPC. 
Results Before treatment, the poor response group exhibited higher values in cluster significance ［(816.40±220.36) vs. (492.13±163.58)］, Haralick correlation ［(12 834.28±875.54) vs. (10 025.14±783.29)］, and apparent diffusion coefficient (ADC) ［(0.85±0.10)×10-3 mm2/s vs. (0.78±0.09)×10-3 mm2/s］ compared with the good response group (P＜0.05). Cluster significance, Haralick correlation and ADC were negatively correlated with the response to radiotherapy and chemotherapy (r=-0.662, -0.594, -0.597, all P＜0.05). Partial regression analysis showed that cluster significance, Haralick correlation and ADC were correlated with the response to radiotherapy and chemotherapy before treatment (P＜0.05). The area under the curve of cluster significance + Haralick correlation + ADC in combination for predicting poor response to radiotherapy and chemotherapy for NPCwas the largest (0.938), with sensitivity of 82.14% and specificity of 89.13%. 
Conclusion MRI texture parameters and DWI parameters are closely related to the response to radiotherapy and chemotherapy in patients with NPC. The combination of cluster significance, Haralick correlation and ADC has high value in predicting the poor response to radiotherapy and chemotherapy in NPC patients. 

Key words: nasopharyngeal carcinoma, MRI texture, response to chemoradiotherapy