OBJECTIVEThis study was to explore the use value of (18)F-FDG PET/CT in patients with extranodal NK/T cell lymphoma (ENKTL).

METHODSBoth PET/CT and CT images were retrospectively analyzed in 43 newly diagnosed patients with ENKTL, and the anatomical position, extent of foci, subtypes, staging and therapeutic regimen determined by both these 2 imaging methods were compared, and relationship between the maximum standard uptake value (SUV(max)) and subtypes, different staging and constitutional symptoms were evaluated.

RESULTSThe top four anatomical positions involved were nose (76.74%), pharynx nasalis (41.86%), Waldeyer's ring (30.23%) and paranasal sinus (27.91%), respectively according to the results of the PET/CT examination, and (18)F-FDG uptake was not found in four patients in the region of upper aerodigestive tract. The PET/CT staging was significantly correlated with constitutional symptoms (P < 0.01). The mean SUV(max) of 43 patients was 13.65 ± 6.35, and the SUV(max) of advanced stages (III/IV) was higher than that of early stage (I/II). Different staging results were found in 21 patients between PET/CT and CT images, 14 patients out of them had direct influence on the treatment plan. Staging of 8 cases was changed from early stage judged by CT image into advaneed stage judged by PET/CT, and radiotherapy regimen of 6 cases at early stage were altered because of the application of PET/CT.

CONCLUSIONThe location and scope of foci in ENKTL patients can be displayed more accurately by PET/CT, the PET/CT is more accurate and reliable than traditional CT image, and has considerable value in determining the treatment plan, and it should be applied in clinical practice widely.