Qingxia Wu1, Shuo Wang2, Xi Chen3, Yan Wang1, Yusong Lin4, and Meiyun Wang1
1Department of Radiology, Henan Provincial People's Hospital, Zhengzhou, China, 2CAS Key Laboratory of Molecular Imaging, Institute of Automation, Beijing, China, 3School of Information and Electronics, Beijing Institute of Technology, Beijing, China, 4Cooperative Innovation Center of Internet Healthcare & School of Software and Applied Technology, Zhengzhou University, Zhengzhou, China
Synopsis
The tumor margin and peritumoral
tissue play an important role in the process of LN metastasis. The aim of this
study was to utilize radiomics analysis of tumor and peri-tumor tissue on T2
weighted image (T2WI) to improve LNM prediction ablility in cervical
cancer patients. We found that peritumoral
tissue of cervical cancer on T2WI showed favorable value in predicting LNM. The
decision tree we proposed which incorporates the radiomics features of
intratumoral and peritumoral tissue on T2WI and c-LN status can be potentially used
for personalized preoperative evaluation of LNM and optimal treatment regimen selection
in cervical cancer patients.
Background and Purpose
Prediction of lymph node metastasis (LNM)
in locally advanced cervical cancer patients is of paramount importance for
treatment regimen selection. Lymphatics in the tumor margin facilitate metastasis
to regional lymph node (LN).
1,2 The peritumoral tissue plays an important role
in the process of LN metastasis. The aim of this study is to utilize radiomics
analysis of tumor and peri-tumor tissue on T2 weighted image (T2WI) to improve
diagnostic performance of LNM in cervical cancer patients.
Materials and methods
A total of 189 consecutive patients with cervical
cancer who were treated between March 2012 and December 2017 were divided into
a training cohort (n=126) and a validation cohort (n=63). All MRI scans were
reviewed by two radiologists with 9 and 8 years of experience in pelvic disease
interpretation. Based on commonly used criteria in daily clinical practice,
patients with the short diameter of largest LN larger than 10mm were regarded
as positive clinical LN (c-LN) status.3 For each patient, we extracted
radiomics features from intratumoral and peritumoral tissues on sagittal T2WI.
Afterwards, the radiomics features associated with LNM status were selected by
univariate ROC testing and logistic regression with the least absolute
shrinkage and selection operator (LASSO) penalty in the training cohort. Based
on the selected features, a support vector machine (SVM) model was established
to predict LNM status. The radiomics workflow is presented in Figure 1. To further improve the diagnostic performance, a
decision tree which combines the radiomics model with clinical factors was built.Results
As shown in Figure 2, radiomics model of the
intratumoral and peritumoral tissue on T2WI (T2tumor+peri) showed best
sensitivity in detecting LNM, with 91.4% and 85.7% in the training and
validation cohort respectively, and the c-LN status showed best specificity,
with 98.8% and 100% in the training and
validation cohort respectively, following by radiomics model of peritumoral tissue. Thus we proposed a decision tree for
personalized evaluation of LNM. First, Radiomics
model of T2tumor+peri was employed to evaluate if the patients have LNM, if LNM
was considered high risk by the model, then we thought LNM was positive for
this patient. If LNM was considered as low risk, c-LN status was employed to
estimate if LNM did not exist. Patient with c-LN status negative was considered
LNM negative and patient with c-LN status positive was considered LNM positive.
The decision tree that combines radiomics model of T2tumor+peri and c-LN status
achieved best diagnostic performance, the AUC, sensitivity, specificity were
0.895, 94.3% and 84.6%; 0.847, 100% and 69.3% in the training and validation
cohorts respectively.Conclusions
The decision tree we built, which incorporates
radiomics model of T2tumor+peri and c-LN status provides personalized
evaluation of lymph node metastasis with high diagnostic performance and can be
potentially applied in the preoperative prediction of LNM in locally advanced
cervical cancer patients.Acknowledgements
This research was supported by the NNSFC (81720108021, 81772009,81601466,81641168, 31470047), National Key R&D Program of China (YS2017YFGH000397), Scientific and Technological Research Project of Henan Province (182102310162) and the Key Project of Henan Medical Science and Technology Project (201501011).References
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