Identification of lymph node metastases by use of whole-body diffusion-weighted imaging in non-small cell lung cancer patients
10.3760/cma.j.issn.1005-1201.2013.07.010
- VernacularTitle:全身MR扩散加权成像在非小细胞肺癌淋巴结转移诊断与鉴别诊断中的价值
- Author:
Yan ZHANG
;
Yongbo HUANG
;
Xixing WANG
;
Jun WANG
- Publication Type:Journal Article
- Keywords:
Lymphatic metastasis;
Carcinoma,non-small-cell lung;
Magnetic resonance imaging
- From:
Chinese Journal of Radiology
2013;(7):622-628
- CountryChina
- Language:Chinese
-
Abstract:
Objective To prospectively and directly compare the capability of whole-body DWI,MRI and/or CT (MRI-CT),and whole-body DWI with MRI-CT for assessment of lymphatic metastases in non-small cell lung cancer (NSCLC) patients.Methods The institutional review board approved this study; informed consent was obtained from patients.A total of 56 NSCLC patients underwent whole-body DWI and thoracic CT scan prospectively.Conventional MRI was performed in suspicious lymphatic metastases parts within one week after inspection.Final diagnosis of the lymphatic metastases in each patient was determined on the basis of results of all radiologic and follow-up examinations.Two chest radiologists independently assessed all examination results and used a five-point visual scoring system to evaluate the probability of metastases.Final diagnosis based on each of the methods was made by consensus of two readers.Receiver operating characteristic (ROC) analysis was used to compare the capability for lymphatic metastases assessment among whole-body DWI,MRI-CT and whole-body DWI with MRI-CT.The detection abilities of lymph nodes with different size were compared with x2 test.Value of apparent diffusion coefficient (ADC) in the differential diagnosis of benign and malignant lymph nodes was compared with the variance analysis.Results (1) Lymph nodes metastases were divided into 3 groups according to the length diameter (＜ 2,2-3,＞ 3 cm).A statistically significant difference (x2 =13.819,P ＜ 0.01) was found in detection of lymph nodes (＜ 2 cm) among whole-body DWI,MRI-CT and whole-body DWI with MRI-CT(within the 123 lymph nodes,109,98 and 117 were detected respectively),whole-body DWI with MRI-CT was superior to conventional MRI-CT(x2 =13.324,P＜0.01).There were no statistically significant difference between the other 2 groups (in the length diameter 2-3 cm group,43,40 and 45 of all 46 lymph nodes were detected respectively by whole-body DWI,MRI-CT and whole-body DWI with MRI-CT,x2 =3.816,P ＞ 0.05,while in the length diameter ＞ 3 cm group,all of the 27 lymph nodes were detected by each of them.(2) Conventional MRI-CT was superior to whole-body DWI in the diagnosis of lymph node metastasis in NSCLC.The area under ROC curve value of whole-body DWI with MRI-CT(Az =0.978),the sensitivity,specificity,accuracy (97.4％ 、88.9％ 、86.3％ respectively) were significantly higher than conventional MRI-CT or whole-body DWI.(3)The ADC value of malignant lymph nodes were significantly lower than those of benign [(0.79 ± 0.15) × 10-3 mm2/s vs (1.59--0.15) × 10-3 mm2/s,F =332.813,P ＜ 0.01].The sensitivity,specificity,accuracy were 100％ with the cut-off value of 1.06 × 10-3mm2/s.Conclusions Whole-body DWI is the beneficial supplements of MRI-CT and can be used as a earlier clinical technique in patients with suspected NSCLC lymph node metastasis.Combined with ADC value,it can be used for assessment and differential diagnosis of lymphatic metastases in NSCLC patients.
