[18F]fluorodeoxyglucose positron emission tomography is more sensitive than skeletal scintigraphy for detecting bone metastasis in endemic nasopharyngeal carcinoma at initial staging.
OBJECTIVE
Bone metastasis occurs frequently in patients with endemic nasopharyngeal carcinoma (NPC). The main objective of this study is to evaluate positron emission tomography (PET) using fluorine-18-labeled fluorodeoxyglucose ([18F]FDG) and conventional skeletal scintigraphy (SS) for detecting bone metastasis at initial staging. Auxiliary objectives are to identify risk factors for bone metastasis and features associated with poor survival in patients with bone metastasis.


METHODS
Patients with endemic NPC before initiation of treatment were enrolled. PET and SS were performed at initial staging and compared using McNemar's paired-sample test. Bone metastasis was considered to be present if there was any reliable evidence identified within 1 year after primary diagnosis. Multiple logistic regression and Cox's proportional hazards models were used for auxiliary objectives.


RESULTS
Thirty (15%) of 202 eligible patients were found to have bone metastasis. [18F]FDG PET was found to be more sensitive than SS in the patient-based analysis (P = .006) and in the region-based analysis at the spine (P = .001). Advanced N stage was the only significant risk factor (P < .0001), and the coexistence of hepatic metastasis was a prognosticator of poor survival (P = .017). The survival was not significantly better for patients with bone metastasis undetected at primary staging than for those with initially detectable bone metastasis (P = .620).


CONCLUSIONS
[18F]FDG PET is more sensitive than SS for detecting bone metastasis in endemic NPC at initial staging, whereas SS can be considered as supplementary in this setting.
Liu
Feng-Yuan
FY
Department of Nuclear Medicine and Molecular Imaging Center, Chang Gung Memorial Hospital, Taipei, Taiwan.
Chang
Joseph T
JT
Wang
Hung-Ming
HM
Liao
Chun-Ta
CT
Kang
Chung-Jan
CJ
Ng
Shu-Hang
SH
Ng
Shu-Kung
SK
Chan
Sheng-Chieh
SC
Yen
Tzu-Chen
TC
D000328:Adult; D000368:Aged; D001859:Bone Neoplasms / Q000000981:diagnostic imaging* / Q000556:secondary; D002277:Carcinoma / Q000000981:diagnostic imaging* / Q000556:secondary; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000473:pathology*; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography / Q000379:methods; D016016:Proportional Hazards Models; D019275:Radiopharmaceuticals; D016019:Survival Analysis
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18