Why was this patient with swollen lymph nodes and normal thyroid function still "pulled into" the endocrinology department?

*For medical professional reading reference only Can you see what's going on? CASE INTRODUCTION A 40-year-old male patient presented with cervical lymphadenopathy on physical examination for 5 days
.

Past history: No specific medical history
.

Physical examination: T: 36.
5℃ P: 80 times/min R: 20 times/min BP: 123/84mmHg, conscious, no yellow staining of skin and sclera, no palpable enlarged lymph nodes in neck, abdominal distention, no gastrointestinal type and peristaltic waves; soft abdomen, mild upper abdominal tenderness, no rebound tenderness, subcostal palpation of liver and spleen, negative Murphy's sign, light percussion pain in liver area, no percussion pain in bilateral kidney area, negative moving dullness, bowel movement The beep can be
.

Laboratory examination: Thyroid examination: the size of the left thyroid lobe is about 20 mm × 15 mm, the size of the right thyroid lobe is about 18 mm × 14 mm, the thickness of the isthmus is about 2.
8 mm, the capsule is smooth, the parenchyma echo is uniform, and no obvious space-occupying lesions are found (Fig.
1)
.

CDFI: There is no obvious blood flow signal in the thyroid
.

A cystic and solid nodule with a size of about 13mm × 11mm was seen in the IV area of ​​the right neck (Figure 2), with clear borders, regular shape, uneven internal echo, and a little liquid anechoic area.
CDFI: a little blood was seen in the nodule flow signal (Figure 3)
.

Figure 1 Two-dimensional color Doppler ultrasound of the thyroid showed normal size and parenchymal echo, and no obvious space-occupying figure 2 Two-dimensional color Doppler showed a lymph node of about 13mm×11mm in the right neck region of the neckFigure 3 Color Doppler showed that there were a few lymph nodes in the lymph node Blood flow signal Q: What is the most likely diagnosis? A.
Reactive hyperplasia of lymph nodes B.
Tuberculous lymphadenitis C.
Metastatic lymph nodes D.
Malignant lymphoma E.
Cat scratch disease Answers Click on the blank space below to get answers Metastatic lymph nodes (papillary thyroid cancer cervical lymph node metastasis) Learning Points▌ Further examination data: the patient had unexplained cervical lymphadenopathy, and subsequent cervical lymph node puncture showed that a small number of cells with nested distribution were seen, with atypia, and papillary thyroid cancer was considered
.

▌ Diagnosis basis: 1.
Male patient, 40 years old, neck lymph node enlargement was found in physical examination for 5 days; 2.
Physical examination was negative; 3.
Three items of thyroid function were negative; Lymph node biopsy showed a small number of cells in nests with atypia, and papillary thyroid carcinoma was considered
.

Considering the above data, metastatic lymph nodes (neck lymph node metastases from papillary thyroid cancer) were considered
.

Seeing this, I believe that most of my colleagues have a big question in their heads, why is the thyroid examination normal, but the cervical lymph nodes have papillary thyroid cancer metastasis? Knowledge expansion: Thyroid cancer is the most common malignant tumor of the human endocrine system.
It is more common in women and can occur at any age.
It is not uncommon under the age of 20
.

Some scholars believe that 10% to 40% of the general population have thyroid nodules, of which 5.
0% to 6.
5% are malignant, and 20% to 25% of single nodules are thyroid cancer.
4% to 10%
.

Cancer nodules less than or equal to 1 cm are called thyroid microcarcinomas, because they are small and difficult to touch, and their onset is occult, also known as occult thyroid cancer
.

According to the pathological type, it can be divided into: 1.
Papillary carcinoma 2.
Follicular carcinoma 3.
Medullary carcinoma 4.
Undifferentiated carcinoma
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Papillary carcinoma is the most common
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Papillary thyroid cancer is very prone to cervical lymph node metastasis.
It has been reported in the literature that about 30%-80% of patients have found lymph node metastasis at the initial diagnosis, and even when the primary lesion in the thyroid is extremely small and cannot be detected by color Doppler ultrasonography, metastasis can occur.

.

Lymph nodes in the central region of the thyroid are regarded as sentinel lymph nodes for papillary thyroid cancer metastasis, and the metastases of lateral cervical lymph nodes come from the central region lymph nodes
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The study found that in addition to the pathway from cancer foci to central lymph nodes and then to lateral cervical lymph nodes, there are many other complex pathways
.

Therefore, we should pay attention to the careful scanning of the lymph nodes in the six regions of the neck in our daily work
.

▌ Ultrasonographic features of cervical lymph node metastasis in papillary thyroid carcinoma: Thyroid cancer generally has ipsilateral cervical lymph node metastasis, multiple around the internal jugular vein; micro-calcifications are often found in the lymph nodes, the cortex is concentrically thickened, and the medullary echo is deformed , narrowed, eccentric and completely disappeared, cystic degeneration may appear in larger lymph nodes; metastatic lymph nodes are rich in blood flow, and lymph nodes that do not show blood flow are mostly hyperplastic lymph nodes
.

▌ Differential diagnosis of swollen neck lymph nodes: 1.
Metastatic lymph nodes (1) Painless, hard, fixed lesions in the neck, supraclavicular fossa, axilla, groin, etc.
under the premise of known or unknown primary disease Swollen lymph nodes
.

(2) On ultrasound, the metastatic lymph nodes are enlarged, round in shape, with an aspect ratio (L/T) <2, generally not fused with each other, most of the borders are sharp, and the cortical echoes are increased and uneven
.

Lymph node hilum may exist in the early stage, but mostly disappear in the later stage
.

Compared with the metastatic lymph nodes without radiotherapy and chemotherapy, the lymph nodes after radiotherapy and chemotherapy tend to have blurred borders, irregular edges, and fusion with each other
.

The marginal zone blood supply is the most specific form of blood supply to metastatic lymph nodes
.

Spectral Doppler showed a high resistance index
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(3) Lymph nodes metastasized from papillary thyroid carcinoma may show characteristic calcification
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Cystic metastatic lymph node changes usually suggest lung squamous cell carcinoma, papillary thyroid carcinoma, and nasopharyngeal carcinoma
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2.
Malignant lymphoma (1) Clinically, the patient has painless and hard lymph node enlargement in multiple locations, which grows rapidly, accompanied by irregular fever, hepatosplenomegaly or blood picture changes
.

(2) On ultrasonography, lymphomas usually show enlarged, rounded, low-weak echoes, L/T<2, sharp borders, disappearance of the lymph node hilum, or irregular eccentric stenosis
.

3.
Reactive lymph node hyperplasia (1) Often caused by local acute and chronic inflammation, the drainage area touches a single or multiple soft and smooth masses, which may be tender and have good mobility
.

(2) Ultrasound showed oval and homogeneous lymph node enlargement, L/T>2, and wide lymph node hilum
.

Color Doppler showed a symmetrical lymph node hilar blood supply, no displacement of the lymphatic hilar vessels, and the RI was about 0.
6
.

4.
Tuberculous lymphadenitis (1) Tuberculosis of superficial lymph nodes occupies the first place in extrapulmonary tuberculosis.
Clinically, there are fusion, fixed, painless masses in the neck and other places, which can be ruptured in the late stage
.

Patients may have tuberculosis lesions in other parts or a history of tuberculosis infection, accompanied by symptoms of tuberculosis systemic poisoning such as fatigue, night sweats, low-grade fever in the afternoon, and weight loss, and tuberculin test (PPD) and/or tuberculosis antibodies are positive
.

(2) On ultrasound, the lymph nodes are enlarged in multiple locations and in clusters, with a rounded shape and uneven internal echoes, showing hypoechoic, anechoic, and mixed with strong echoes, the lymph node hilum is shifted, narrowed or disappeared, and the border of the lymph node is blur, blend
.

References: [1] Geng Yaxing.
Analysis of clinical features and evaluation of lymph node metastasis in lateral cervical region of papillary thyroid carcinoma [D].
Jilin University, 2021.
DOI: 10.
27162/d.
cnki.
gjlin.
2021.
001526.
[2] Li Spring, "Superficial Organ Ultrasound Medicine".