PT - JOURNAL ARTICLE AU - Yoon, Mee Sun AU - Nam, Taek-Keun AU - Chung, Woong-Ki AU - Jeong, Shin Young AU - Ahn, Sung-Ja AU - Nah, Byung-Sik AU - Song, Ju-Young AU - Jeong, Jae-Uk TI - Metabolic Response of Pelvic and Para-Aortic Lymph Nodes During Radiotherapy for Carcinoma of the Uterine Cervix: Using Positron Emission Tomography/Computed Tomography AID - 10.1111/IGC.0b013e3181e94349 DP - 2011 Apr 01 TA - International Journal of Gynecologic Cancer PG - 699--705 VI - 21 IP - 4 4099 - http://ijgc.bmj.com/content/21/4/699.short 4100 - http://ijgc.bmj.com/content/21/4/699.full SO - Int J Gynecol Cancer2011 Apr 01; 21 AB - Objectives: We evaluated the metabolic response of lymph nodes (LNs) using consecutive 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (PET/CT) and correlated the metabolic response with the volumetric response measured by consecutive CT.Methods: Twenty-two patients with cervical cancer that had positive LNs underwent preradiotherapy (pre-RT) and inter-RT PET/CT. The metabolic response of the LNs was assessed quantitatively and semiquantitatively by measurement of the maximal standardized uptake value. All patients underwent inter-RT CT simulation after 45 Gy to the whole pelvis and inter-RT PET/CT scans after median 63 Gy to the gross LNs.Results: A total of 48 pelvic and para-aortic LNs were found on the pre-RT PET/CT. The mean maximal standardized uptake value of nodal disease decreased from the pre-RT of 5.2 (SD, 3.1; range, 1.8-15.6) to the inter-RT of 1.1 (SD, 2.1; range, 0-11.1). Classifying the metabolic response of all 48 nodal lesions on the inter-RT PET/CT, 38 had a complete metabolic response. The initial volume of LNs had no correlation with the metabolic response (r = 0.194, P = 0.186). The metabolic response between the pre-RT PET/CT and inter-RT PET/CT was significantly associated with the volume response between the pre-RT CT and inter-RT CT (r = 0.314, P < 0.05). However, 18 (38%) LNs showed discrepancy between metabolic response and residual LN volume. Six (27%) patients had modified RT during treatment based on inter-RT PET/CT.Conclusions: We suggest that the PET/CT can be a useful tool for the evaluation of the interim response of the LNs and aid in selecting patients that need further treatment. The results showed a significant correlation between the metabolic and volumetric responses during RT, although the anatomical changes of LNs would not always represent the metabolic status.