[18F]-Fluorodeoxyglucose Positron Emission Tomography Standardized Uptake Value as a Predictor of Adjuvant Chemotherapy Benefits in Patients With Nasopharyngeal Carcinoma.

BACKGROUND

The role of adjuvant chemotherapy for the treatment of nasopharyngeal carcinoma (NPC) is controversial, and the identification of adequate predictive factors is warranted. Therefore, we aimed to investigate whether the mean standardized uptake value (SUV) measured on [(18)F]-fluorodeoxyglucose (FDG) positron emission tomography (PET) could predict the survival benefits for NPC patients that receive adjuvant chemotherapy.

MATERIALS AND METHODS

The data for 174 NPC patients who underwent PET/computed tomography before chemoradiation between January 2004 and January 2012 were reviewed. The SUV75% was recorded for primary tumors. All patients received intensity-modulated radiotherapy and cisplatin-based chemotherapy. Adjuvant chemotherapy consisted of 3 cycles of 75 mg/m(2) cisplatin and 1,000 mg/m(2) fluorouracil for 4 days.

RESULTS

The optimal cutoff value was 8.35 for SUV75%, with 112 (64.4%) patients having lower SUV75% and 62 (35.6%) having higher SUV75%. Patients with lower SUV75% had significantly better 5-year overall survival (OS) and distant metastasis-free survival. Multivariate analysis revealed that tumor stage, SUV75%, and adjuvant chemotherapy were significant prognostic factors for OS. Patients with higher SUV75% had significantly higher 5-year OS rates with adjuvant chemotherapy than without adjuvant chemotherapy (84.3% vs. 32.4%, respectively; p < .001). However, in the lower SUV75% group, no differences in 5-year OS were observed between patients who received and those who did not receive adjuvant chemotherapy (92.4% vs. 93.3%, respectively; p = .682).

CONCLUSION

The SUV75% on FDG PET for primary tumors could successfully identify NPC patients who may benefit from adjuvant chemotherapy.