This poster is published under an
open license. Please read the
disclaimer for further details.
Keywords:
Thyroid / Parathyroids, Elastography, Outcomes analysis, Metastases
Authors:
W. S. Jung1, J.-A. Kim2, E. J. Son2, J. H. Youk2, C. S. Park1; 1 Seoul/KR, 2Seoul/KR
DOI:
10.1594/ecr2014/C-0489
Aims and objectives
Papillary thyroid carcinoma (PTC) spreads to regional lymph nodes frequently,
but rarely causes distant metastases.
PTC involves metastasis to cervical lymph nodes in 30 - 80% of patients,
and recent studies have revealed that regional lymph node metastasis has an adverse prognostic impact on survival,
especially in older patients ( ≥ 45 years).
PTC recur most frequently at the cervical lymph nodes and locoregional recurrences are reported in up to 31% of patients.
Such high rates of recurrence suggests that many patients have lymph node metastases at the time of initial surgery,
and that if these metastases can be detected preoperatively and removed by surgery,
future cervical recurrence and patient morbidity will be reduced.
Therefore,
there is a need for a preoperative imaging tool to predict metastatic PTC to cervical lymph nodes and assess the prognostic implication of lymph node metastasis.
A firm and hard thyroid nodule on palpation is known to be associated with an increased risk of thyroid malignancy.
Ultrasound (US) elastography has been introduced to evaluate the tissue hardness more objectively.
SWE utilizes focused pulses of ultrasound to stimulate tissues,
an ultrafast US method to track the shear waves,
and displays real-time output on elastogram either in terms of shear wave velocity or estimated tissue stiffness.
As SWE permits absolute quantification of tissue stiffness,
it represents a significant advance over conventional (strain) elastography that at best produces semiquantitative estimates corresponding to relative tissue strain and SWE is less operator-dependent than conventional elastography.
In recent studies show that SWE values in malignant thyroid nodules are significantly higher than in benign nodules and quantitative information of elasticity could predict the pathologic prognostic factors.
The objectives of this study
-to evaluate the diagnostic performance of quantitative SWE for predicting cervical lymph node metastasis in PTC patients
-the prognostic implication of SWE as a predictor of histopathologic factors of cervical LN metastasis