Value of apparent diffusion coefficient values in predicting induction chemotherapy response of advanced nasopharyngeal carcinoma / 实用放射学杂志

ABSTRACT

Objective To predict the response of induction chemotherapy in advanced nasopharyngeal carcinoma (NPC)by using pretreat-ment apparent diffusion coefficient (ADC)values.Methods 35 patients with advanced NPC underwent DWI examination prior to 2-week in-duction chemotherapy.The patients were divided into CR (complete response)group,PR (partial response)one and SD (stable disease)one according to the tumor response of treatment.The effective responders included CR and PR groups.The patients were divided into children-adolescents(below 20 years)group and adults one according to the age,into non-keratinizing undifferentiated carcinoma group and non-kera-tinizing differentiated carcinoma one according to the pathological type,and also into T2,T3 and T4 groups according to the T-staging (UICC2010).Statistical analysis was used to compare the pretreatment ADC values between different groups.Results The average pre-treatment ADC values of CR,PR,responders and SD groups were (0.70±0.06)×10 -3 mm2/s,(0.72±0.04)×10 -3 mm2/s,(0.71± 0.04)×10 -3 mm2/s and (0.85±0.02)×10 -3 mm2/s respectively.The average pretreatment ADC value of the SD group was signif-icantly higher than that of PR group and responders,and the differences were significant (P <0.05).The average pretreatment ADC value of children-adolescents and adults groups were (0.73±0.07)×10 -3 mm2/s and (0.75 ±0.07)× 10 -3 mm2/s,which showed no significant differences.The average pretreatment ADC value of non-keratinizing undifferentiated carcinoma and non-keratinizing dif-ferentiated carcinoma groups were (0.76 ±0.08)×10 -3 mm2/s and (0.74±0.06)×10 -3 mm2/s,which showed no significant differ-ences.The average pretreatment ADC values of T2,T3 and T4 groups were (0.78±0.05)×10 -3 mm2/s,(0.77 ±0.07)×10 -3 mm2/s and (0.75±0.08)×10 -3 mm2/s.Although there were no significant differences between T2,T3 and T4 groups,a trend towards lower ADC was observed with increasing tumor T-staging.Conclusion Pretreatment ADC value is a valuable quantitative parameter,and it can be used for predicting induction chemotherapy response in advanced naso-pharyngeal carcinoma.