Clinical Values of PET-CT Compared to Conventional Radiologic Imaging in Head & Neck Cancer

Kim, Jae Won; Ko, Kook Jin; Yoon, Suk Young; Lee, Seung Ho; Kim, Young Mo

Abstract

BACKGROUND AND OBJECTIVES
: In head & neck cancer, the conventional CT and MRI are useful methods in imaging the anatomical structures of cancer, but they have limits in estimating sensitivity and specificity. To overcome these limits, PET-CT, an imaging technique using metabolism emitting from cancer tissues, was introduced. This study was aimed to evaluate the clinical values of PET-CT by comparing the PET-CT of the conventional CT/MRI, with respect to imaging primary lesions, finding metastatic cervical lymph nodes, and discovering any tumor or recurrence. MATERIALS AND METHOD : Seventy patients, who were diagnosed with head and neck cancer, were selected from Inha Hospital from March, 2004 to July, 2005. For every patient selected, a retrospective analysis was done by medical record review. The studied patients were divided into group 1 and 2. Group 1 was composed of patients that had preoperative evaluation for staging, group 2 with follow-up patients after primary treatment. In group 1, the analysis was done by comparing pathohistologic results from PET-CT to CT/MRI findings and in group 2, radiologic imaging studies were compared by follow-up imaging or clinical manifestation after 6 months.
RESULTS
: For the primary sites, 22 cases were laryngeal cancers, and 17 cases were thyroid. For primary site cancers and metastatic lymph nodes in group 1 and 2, there were no statistical differences of sensitivity, specificity and predictability between CT/MRI and PET-CT imaging.
CONCLUSION
: We were not able to prove the clinical values of PET-CT, since PET-CT had no meaningful differences from the conventional methods in imaging primary lesions, finding metastatic cervical lymph nodes, and follow-up.