Tài liệu Diagnostic value of ultrasound elastography in thyroid cancer – Hoang Dinh Anh: Journal of military pharmaco-medicine n
o
1-2019
158
DIAGNOSTIC VALUE OF ULTRASOUND ELASTOGRAPHY
IN THYROID CANCER
Hoang Dinh Anh1; Pham Thi Dieu Huong1; Nguyen Thi Hoang Oanh1
Nguyen Minh Hai1; Nguyen Thi Ha1; Nguyen Thi Ly1; Nguyen Vu Thang1
SUMMARY
Objectives: To describe some clinical features of thyroid nodules, B-mode ultrasound,
Doppler and strain elastography in order to differentiate benign from malignant tumors. Subjects
and methods: 72 patients with thyroid nodules were performed clinical examination, 2D ultrasound,
Doppler and strain elastography for qualitative assessment of the stiffness of thyroid tumors
according to Asteria scores (2008) from ES1 - ES4, semi-quantitative calculating elasticity of the
tumors (E2) and normal parenchyma (E1), strain ratio: SR = E2/E1, comparing with fine needle
aspiration results. Results: The study group had mean age of 47.31 ± 12.91, most of them were
female. B-mode ultrasound: suspicious features of malign...
8 trang |
Chia sẻ: Đình Chiến | Ngày: 06/07/2023 | Lượt xem: 303 | Lượt tải: 0
Bạn đang xem nội dung tài liệu Diagnostic value of ultrasound elastography in thyroid cancer – Hoang Dinh Anh, để tải tài liệu về máy bạn click vào nút DOWNLOAD ở trên
Journal of military pharmaco-medicine n
o
1-2019
158
DIAGNOSTIC VALUE OF ULTRASOUND ELASTOGRAPHY
IN THYROID CANCER
Hoang Dinh Anh1; Pham Thi Dieu Huong1; Nguyen Thi Hoang Oanh1
Nguyen Minh Hai1; Nguyen Thi Ha1; Nguyen Thi Ly1; Nguyen Vu Thang1
SUMMARY
Objectives: To describe some clinical features of thyroid nodules, B-mode ultrasound,
Doppler and strain elastography in order to differentiate benign from malignant tumors. Subjects
and methods: 72 patients with thyroid nodules were performed clinical examination, 2D ultrasound,
Doppler and strain elastography for qualitative assessment of the stiffness of thyroid tumors
according to Asteria scores (2008) from ES1 - ES4, semi-quantitative calculating elasticity of the
tumors (E2) and normal parenchyma (E1), strain ratio: SR = E2/E1, comparing with fine needle
aspiration results. Results: The study group had mean age of 47.31 ± 12.91, most of them were
female. B-mode ultrasound: suspicious features of malignance: ill-defined margin (50%); taller-
than-wide (11.1%); micro-calcification (13.9%). Ultrasound elastography: 45.8% of patients were
classified as ES3 (hard) and ES4 (very hard); strain ratio SR: 2.51 ± 1.18. A comparison of
these results with post-operative biopsy showed that the highest sensitivity and specificity were
obtained with SR ≥ 2.5. Conclusion: Qualitative assessment of the elasticity of lesions using
color map in combination with calculating mean strain ratio of the whole lesion (SR ≥ 2.5) would
help to evaluate more exactly the stiffness of lesions on elastography to assess thyroid cancer.
* Keywords: Thyroid tumor; Ultrasound elastography; Diagnosis.
INTRODUCTION
Thyroid nodule is the second most
common endocrine disease, after diabetes.
The prevalence of the disease diagnosed
by physical examination only accounts for
4 - 7%. However, with ultrasound technology,
the rate of thyroid nodule detection may
reach to 19 - 67%. More than 90% of
thyroid tumors are benign adenomas and
cysts, only 5 - 10% are malignant nodules.
Therefore, early detection and treatment
for patients with malignant nodules as
well as recognizing patients with benign
disease without the need of fine needle
aspiration (FNA) are required.
So far, ultrasound is still the main
method of diagnistic image of thyroid
disease. However, with a diagnosed
thyroid tumor, the indication of FNA is
quite excessive. This increases the
number of unecessary FNA performance,
which is financial burden and especially
makes a stress to the patients. For routine
follow-up without FNA, some researchers
have recently introduced a new technique -
elastography.
1. 103 Military Hospital
Correspoding author: Pham Thi Dieu Huong (huongdr106@gmail.com)
Date received: 20/10/2018
Date accepted: 03/12/2018
Journal of military pharmaco-medicine n
o
1-2019
159
This technique allows to evaluate the
biological properties of body tissues
based on the principle that when a force
is applied to the body tissue, it causes the
tissue to deform or move. Normal (soft)
tissue is more distorted but less translocated,
while pathological tissue (harder), is less
distorted and more translocated. The
hardness of the tissue is calculated
from the corresponding deformation and
displacement.
Studies in evaluating the effect of
ultrasound elastography on focal lesions
in general and thyroid nodules in particular
in our country are not much. To contribute
to the studies and assertion of the value
of ultrasound elastography, proceeding to
apply this modality daily in the hospital,
we conducted this study with the aims to:
Evaluate some clinical features, 2D
ultrasound and elastography of thyroid
nodules, value of ultrasound elastography
in diagnosis of malignant nodules.
SUBJECTS AND METHODS
1. Subjects.
72 patients were diagnosed with thyroid nodule from 10 - 2015 to 10 - 2016 at
Department of Functional Exploration, 103 Military Hospital.
2. Methods.
* Study design:
Cross-sectional study.
- 2D and color Doppler ultrasound were performed to evaluate the size and structure
of thyroid parenchyma as well as the position, morphology and vascularity of thyroid
nodules. Kwak's TIRADS classification relies on signs of malignancy as following:
- Solid nodule.
- Hypoechogenicity or marked hypoechogenicity.
- Microlobulated or irregular margins.
- Microcalcifications.
- Taller-than-wide shape.
- Elastography: Score ES3 - ES4, Strain ratio ≥ 2.5.
Tables 1:
TI-RADS Description Risk of malignancy
1 Normal Normal thyroid gland 0%
2 Benign
Cyst, spongiform nodule
Macrocalcifications
Hyperechogenicity
0%
3 Probably benign
Hyper or iso-echoic, regular shape
and borders, peripheral
vascularization
< 5%
Journal of military pharmaco-medicine n
o
1-2019
160
4A Low suspicion for
malignancy One suspicious feature 5 - 10%
4B Moderate suspicion for
malignancy Two suspicious features 10 - 80% 4
4C Moderate concern but not
classic for malignancy Three to four suspicious features > 80%
5 Biopsy proven malignancy All five suspicious features or
metastatic lymph nodes
* Elastography criteria:
Patients with multi-nodular in one or two thyroid lobes, ultrasonography was performed
with one that has malignant signs on the 2D ultrasound.
- Qualitative hardness of nodules were evaluated based on prominent color of the
nodules according to the classification proposed by Asteria et al (2008). Color scale of
the hardness: ES1 - ES4.
- Semi-quantitative assessment of the hardness: Drawing the circumference of nodules,
calculating the average elasticity index (E2). The region of interest (ROI) at the same
depth was calculated as the elasticity index of the benign parenchyma (E1).
Then calculate the SR (Strain ratio) according to the formula: SR = E2/E1.
Picture 1: Color scale in respond to different hardness of thyroid nodules
(from ES1 to ES4) and calculation of SR on elastography in one patient.
* Data analysis: Data were analyzed by SPSS 16.0, percentage, average value,
sensitivity level, specificity, the accuracy of the method compared with the
pathological results.
Journal of military pharmaco-medicine n
o
1-2019
161
RESULTS AND DISCUSSION
1. General characteristics of the study group.
In our study, 72 patients were diagnosed with thyroid nodules by clinical examination
and 2D ultrasound. They were selected randomly from patients who admited to
103 Military Hospital for ultrasound examination or for thyroid surgery. All patients were
performed FNA or histologically diagnosed after surgery. We examined 2D ultrasound
and strain elastography of thyroid tumor before having histological results. The results
of the study group:
Table 2: Some clinical characteristics of the study group.
n = 72 %
Age (mean) 47.31 ± 12.91
Male 4 5.6
Gender
Female 68 94.4
One 41 56.9
Quantity
Many 31 43.1
Right lobe 28 38.9
Left lobe 16 22.2
Physical examination of
thyroid tumor
Location
Two lobe 28 38.9
Soft 42 58.3
Tumor density
Hard/firmness, less movement 30 41.7
Yes 6 8.3
Lymph nodes in the neck
No 66 91.7
The study group was mainly middle-aged with an average age of 47.31 ± 12.91 years old;
most of them were female (94.4%).
Clinical examination: It is difficult to detect cancer markers, only suspicious features
of malignance are the feature of firmness, less movement. We found this symptom in
30/72 patients (41.7%). In terms of age, sex and clinical characteristics suspect
thyroid cancer, our results were similar to those of other authors’s studies such as
Tran Ngoc Dung [1] in 1,181 patients with thyroid carcinoma, showed an average age
of 41.3 ± 8.9 years, the most common age was 30 - 49 years (45.97%), Nguyen Huu Thinh
(2012) [2] in 44 patients with thyroid tumor, mean age: 45 years old, female accounted
for 81.8%, clinical diagnosis suspected malignant in 40.9%.
Journal of military pharmaco-medicine n
o
1-2019
162
2. Features of 2D ultrasound, Doppler and TIRADS classification.
Table 3: 2D ultrasound features of thyroid tumor.
Ultrasound characteristics n = 72 %
Solid 50 69.4
Cystic 3 4.2 Composition
Mixed 19 26.4
Hyperechoic 0 0
Hypoechoic 21 29.2
Isoechoic 26 36.1
Echogen
Mixechoic 25 34.7
Defined 36 50.0
Margin
Ill-defined 36 50.0
< 10 mm 19 26.4
Size
> 10 mm 53 73.6
Tall > wide 8 11.1
Shape
Wide > tall 64 88.9
Micro-calcification 10 13.9
Coarse-calcification 11 15.3 Calcification
No calcification 51 70.8
The diagnosis of thyroid tumors mainly relied on 2D ultrasound and Doppler.
Nguyen Huu Thinh [2] studied 44 patients with thyroid nodules showed suspicious
features of malignance such as hypoechoic structure (47.7%); calcification (31.8%);
ill-defined margin (25%). Our results were similar with suspicious features of malignance
such as hypoechoic structure (29.2%); ill-defined margin (50%); taller than wide (11.1%);
micro-calcification (13.9%). If only every suspected malignant sign on 2D ultrasound,
the diagnosis is more difficult.
Then, we categorized TIRADS of thyroid tumor:
Figure 1: TIRADS classification.
Journal of military pharmaco-medicine n
o
1-2019
163
Kwak (2011) [6] based on 5 malignant signs on 2D ultrasound for grading of
TIRADS. Our results: 60 patients (83.3%) of TIRADS 2 and TIRADS 3. There was no
image suspected malignant. 12 patients (16.6%) had 1 to 4 signs of malignancy with
TIRADS 4. This group of patients should be further investigated by FNA for diagnosis.
3. Result of strain elastography in thyroid tumor.
Figure 2: Ultrasound elastography window with satisfactory force compression,
full blue column, ES4 color pattern (patient B.T.H.Y 26 years old).
After performing 2D ultrasound, classified nodules according to TIRADS, all patients
were performed strain elastography. Patients with multiple nodules in one or two
thyroid lobes, strain elastography at the highest TIRADS category nodule was selected.
Strain elastography was performed by continuous compression, with moderate force,
reaching the standardized display of full blue bars on the screen. Thereby, hardness
assessment of the tumor by the color on the elasticity map.
Table 4: Elasticity map of thyroid nodule.
Strain elastography (ES) Patients (n = 72) Percent (%)
ES 1 (soft) 4 5.6
ES 2 (soft - hard) 35 48.6
ES 3 (hard) 28 38.9
ES 4 (very hard) 5 6.9
The results showed that 33/72 patients (45.8%) had solid and hardened tumors
(ES3 - ES4), which were considered to be malignant. However, this is a qualitative
sign, the diagnostic value is not high. We continued to evaluate the elastic parameters,
which are more objective than the color spectrum.
Journal of military pharmaco-medicine n
o
1-2019
164
Table 5: Strain elastography parameters.
Mean Min Max
E1 1.19 ± 0.54 0.6 3.3
E2 2.6 ± 0.98 1.0 4.6
SR (E2/E1) 2.51 ± 1.18 0.6 5.7
≥ 2.5 23 patients (31.9%)
SR value
< 2.5 49 patients (68.1%)
For qualitative assessment of thyroid
tumor by strain elastography: We performed
continuous pressure for 6 seconds,
measuring elasticity index by drawing
the perimeter of the entire tumor (E2),
compared with that of benign parenchyma
at the same depth (E1). Value of E2
(2.6 ± 0.98) was significantly higher than E1
(1.19 ± 0.54). Strain ratio = 2.51 ± 1.18.
Compared with the results of the study by
Nguyen Huu Thinh [2] (SR: 2.76 ± 0.41),
our results were lower, because our study
group was mainly benign and SR is valuable
for hardness assessment of malignant
nodules.
4. The sensitivity, specificity of strain
elastography ultrasound compared
with FNA and histology results.
Table 6: The sensitivity, specificity of
strain elastography.
Histopathology
Elasticity pattern
Malignant Benign Total
ES3 - ES4 10 13 23
ES1 - ES2 2 47 49
Total 12 60 72
We found that tumors with ES3 and
ES4 types were high risk malignant tumors,
compared with results of histology after
surgery. We suggested that SR value > 2.5
is significant in the diagnosis of cancer
with sensitivity 83.3%; specificity 78.3%;
accuracy 79.1%.
Our results were similar to the results
of Sahin’s study [5]: SR > 2.45 is a sign to
diagnose thyroid cancer on ultrasound
elastography with the sensitivity of 73.9%
and the specificity of 73%.
Strain elastography combined with 2D
ultrasound, TIRADS classification increased
sensitivity, specificity and accuracy to
91.7%, 98.3%; and 98.3%, respectively.
According to Gilles Russ (2013) [7]:
2D ultrasound, TIRADS classification
combined with ultrasound elastography
will increase the diagnostic sensitivity of
thyroid cancer to 98.5%.
In some recent studies, the authors
used strain elastography to assess the
malignancy of thyroid tumors. However,
it is rare for the authors to calculate the
strain ratio through the mean elasticity
index of the whole tumor. In this study,
if an ultrasound of TIRADS 4B or above,
combined with ultrasound elastography
with ES3 or ES4 color pattern, and strain
ratio SR ≥ 2.5, the possibility of malignancy
is very high.
CONCLUSION
Strain elastography is a simple, easy
to perform, effective, non-invasive method.
Qualitative assessment of the elasticity of
lesions using color map in combination
with calculating mean strain ratio of the
whole lesion (SR ≥ 2.5) would help to
evaluate more exactly the stiffness of lesions
on elastography to assess thyroid cancer.
Journal of military pharmaco-medicine n
o
1-2019
165
REFERENCE
1. Trần Ngọc Dũng. Nghiên cứu mô bệnh
học lâm sàng 1,118 trường hợp ung thư biểu
mô tuyến giáp. Chuyên đề Bệnh viện Quân y
103. Học viện Quân y. 2010, tr.172-175.
2. Nguyễn Hữu Thịnh. Nghiên cứu đặc
điểm siêu âm đàn hồi mô ở bệnh nhân u
tuyến giáp. Luận văn Thạc sỹ Y học. Đại học
Y Huế. 2012.
3. Asteria C, Giovanardi A, Pizzocaro A
et al. US-elastography in the differential
diagnosis of benign and malignant thyroid
nodules. Thyroid. 2008, 18, pp.523-531.
4. Gilles Russ et al. Prospective evaluation
of thyroid imaging reporting and data system
on 4,550 nodules with and without elastography.
Eur J Endocrinol. 2013, 168, pp.649-655.
5. Kwak J.Y, Han K.H, Yoon J.H et al.
Thyroid imaging reporting and data system for
US features of nodules: a step in establishing
better stratification of cancer risk. Radiology.
2011, 260, pp.892-899.
6. Rago T, Santini F, Scutari M, Pinchera
A, Vitti P. Elastography: New developments in
ultrasound for predicting malignancy in thyroid
nodules. J Clin Endocrinol Metab. 2007, 92,
pp.2917-2922.
7. Sahin M, Cakal E, Ozbek M et al.
Elastography in the differential diagnosis of
thyroid nodules in Hashimoto thyroiditis.
Med Oncol. 2014, 31, p.97.
Các file đính kèm theo tài liệu này:
- diagnostic_value_of_ultrasound_elastography_in_thyroid_cance.pdf