Abstract: Abstract： Objective To investigate the influencing factors of 18 F- FDG uptaking in head and neck malignancy by SPECT/CT coincidence imaging. Methods 18 F-FDG SPECT/CT coincidence imaging was performed in 32 patients with head and neck malignancy after surgery, radiotherapy or radiotherapy + chemotherapy. The radio of target/no target (T/N) was calculated. The gender, age, fasting blood glucose level, size of tumor, location of tumor, pathological classification, de⁃ gree of cell differentiation and treatment modalities were analyzed between groups. Results The single-factor analysis of variance showed that the T/N value was significantly higher in >70 yeas old, group than that of 41-50 yeas old group and 51-60 yeas old group (P < 0.05). The T/N value was significantly lower in tumor size <2 cm group than that of 2-5 cm group and > 5 cm group (P＜0.05). And it was lower in poor differentiated tumor group than that of. undifferentiated tumor group (P < 0.05). There were no significant differences in T/N values between other indicator groups (P > 0.05). The multiple linear regression analysis showed that 18 F-FDG uptaking in head and neck malignancy (T/N=Y) was related to the age of patients (X2), the diameter of tumor (X4) and the degree of cell differentiation (X9): =-4.389 25+0.053 03 X2+1.617 86 X4+ 0.718 35 X9. Conclusion Tumor recurrence is more likely to occur in patients with age >70 years old, the diameter of tumor ≥2 cm, and the anaplastic head and neck malignancy.We should pay much attention to the diagnosis and follow-up for these pa⁃ tients.

Key words: head and neck neoplasms, neoplasm recurrence, local, radionuclide tomography, single photon emission omputed, deoxyglucose, coincidence