BACKGROUND: We investigated whether the addition of narrow band imaging (NBI) to standard diagnostic workups could enhance the detection of primary lesions in patients with carcinoma of unknown primary (CUP). METHODS: Thirty patients with CUP underwent NBI endoscopy and fluorodeoxyglucose-positron emission tomography/CT (FDG-PET/CT) after thorough conventional diagnostic workups between 2009 and 2011. Sites suspected of harboring primary tumors, as determined by NBI and/or FDG-PET/CT, were biopsied for histologic confirmation. RESULTS: Occult primary tumors were identified in 33.3% (10/30), including 13.3% (4/30) by NBI and 20.0% (6/30) by FDG-PET/CT. All of diagnosed lesions by NBI were confirmed histologically as squamous cell carcinomas with T1 classification and identified at 2 supraglottis, 1 hypopharynx, and 1 esophagus, respectively. CONCLUSIONS: NBI endoscopy may be a useful method for detecting primary tumors, especially for small and superficial squamous cell carcinomas of the upper aerodigestive tract, after conventional workup in patients with CUP.
BACKGROUND: We investigated whether the addition of narrow band imaging (NBI) to standard diagnostic workups could enhance the detection of primary lesions in patients with carcinoma of unknown primary (CUP). METHODS: Thirty patients with CUP underwent NBI endoscopy and fluorodeoxyglucose-positron emission tomography/CT (FDG-PET/CT) after thorough conventional diagnostic workups between 2009 and 2011. Sites suspected of harboring primary tumors, as determined by NBI and/or FDG-PET/CT, were biopsied for histologic confirmation. RESULTS:Occult primary tumors were identified in 33.3% (10/30), including 13.3% (4/30) by NBI and 20.0% (6/30) by FDG-PET/CT. All of diagnosed lesions by NBI were confirmed histologically as squamous cell carcinomas with T1 classification and identified at 2 supraglottis, 1 hypopharynx, and 1 esophagus, respectively. CONCLUSIONS: NBI endoscopy may be a useful method for detecting primary tumors, especially for small and superficial squamous cell carcinomas of the upper aerodigestive tract, after conventional workup in patients with CUP.