Objective: Various methods have been reported for the detection of unknown primaries in cervical lymph node metastasis. Recently, we applied new optical devices and modifications of endoscopic techniques for the detection of primary lesions, and obtained excellent results. The detection rate of the new method was compared with that of previous methods.
Study design: Retrospective.
Methods: A total of 51 patients with cervical lymph node metastasis from an unknown primary site (CUP) were referred to our hospital between January 2000 and May 2009, and were retrospectively analyzed. Between 2000 and 2005, the observation by normal video-endoscope in straight head position was performed to detect the primary lesions in the outpatient setting. Since 2006, a new method for detection of primary lesions has been employed. The method includes the use of new optical devices (hooded video-endoscope and narrow-band imaging endoscope) and different head positions (head torsion technique, Valsalva maneuver, and the Killian position).
Results: The detection rate of primary lesions using the new method was 71% (15 of 21), which was better than the 30% (10 of 30) obtained with the conventional method. All primary lesions identified using the new method were located in the hypopharynx.
Conclusions: The new method was able to detect primary lesions in 71% of cases with CUP. The higher rate achieved with the new method was probably due to the clear visualization of the hypopharynx. Thus, the new method was shown to be useful for the detection of primary lesions in cases of CUP.