Eugene K Choi MD, Presenter: Nothing to Disclose

Jeong Kon Kim MD, Abstract Co-Author: Nothing to Disclose

Hyuck Jae Choi MD, Abstract Co-Author: Nothing to Disclose

Bum-Woo Park, Abstract Co-Author: Nothing to Disclose

Namkug Kim PhD, Abstract Co-Author: Nothing to Disclose

Kyoung-Sik Cho MD, Abstract Co-Author: Nothing to Disclose

To perform node-by-node comparison of diffusion-weighted imaging (DWI) and size-based criteria on T2-weighted imaging (T2WI) for detection of pelvic lymph node (LN) metastasis in cervical cancer patients using PET/CT as the reference standard.

We included 163 patients with 340 pelvic LN with the short-axis diameter equal to or greater than 5 mm. A threshold ADC was obtained by receiver-operating-characteristic analysis of the testing set (n = 50) and subsequently applied to the training set (n =113). In the training set, two reviewers measured the short- and long-axis diameters on T2WI and apparent-diffusion coefficient (ADC) in pelvic LNs. The ADC, short-axis diameter, and long-to-short diameter (L/S)-ratio were compared between metastatic and non-metastatic LNs. Using the results of PET/CT as the reference standard, the detection of LN metastasis was compared on per-node and per-patient bases between DWI and and the followng size-based criteria on T2WI : short-axis diameter (8 mm, 9 mm, and 10 mm) and a long-to-short diameter (L/S)-ratio of 1.25.

The mean ADC, short-axis diameter, and L/S-ratio were significantly different between metastatic (0.6500, 10.5 cm, and 1.23, respectively) and non-metastatic LNs (0.8689, 7.6 cm, and 1.43, respectively) (P<.001). From the receiver-operating-characteristic analysis (Az = .911) of the testing set, an ADC of 0.710 was demonstrated as the optimal threshold. Per-node sensitivity and specificity for detecting metastatic LNs by ADC were 82% (73/89) and 76% (116/152), respectively. The sensitivity of ADC was significantly greater than those of the short-axis diameter criteria (37%-64%) and L/S-ratio criterion (58%) (P <.0001). Per-patient accuracy of ADC (92%) was greater than all short-axis diameter criteria (66%-81%) and the L/S-ratio criterion (73%) (P<.05).

DWI can improve the diagnostic accuracy of MR in the detection of metastatic pelvic LNs in cervical cancer patients, as it is more sensitive than T2WI.

With the addition of diffusion-weighted imaging, MR examination can significantly improve the assessment of tumor lymphatic spread and thereby improve the care of patients with cervical cancer.

Choi, E, Kim, J, Choi, H, Park, B, Kim, N, Cho, K, Diagnosis of Metastatic Pelvic Lymphadenopathy in Uterine Cervical Cancer: Node-by-Node Comparison of Diffusion-weighted Imaging and Size-based Criteria on T2WI with PET/CT as the Reference Standard.  Radiological Society of North America 2008 Scientific Assembly and Annual Meeting, February 18 - February 20, 2008 ,Chicago IL. http://archive.rsna.org/2008/6015317.html