In the past 20 years, the incidence of thyroid cancer in China has soared 20 times! Especially in women, the incidence of thyroid cancer has increased sharply, approaching the first breast cancer. Let's start paying attention to this once unattractive malignancy.
Thyroid cancer mostly develops from thyroid nodules. The incidence of thyroid nodules in China is very high, usually discovered during routine physical examinations or inadvertently. There is no need to panic about finding thyroid nodules, as most nodules are benign and only 1 to 5% may be malignant. However, there is a situation where the nodule is "calcified" and needs to be vigilant.
If the thyroid nodule is calcified, is it most likely a malignant tumor?
Xiao Liu, a young man who is less than 30 years old this year, found that there were thyroid nodules in the unit physical examination, and then did a B ultrasound examination and heard his nodules "calcified", and it was not small. When he got the test results, he kept beating drums in his heart, because he heard that the nodules were calcified, and the possibility of malignancy was very high, so he came to consult us. So, the "calcification" of thyroid nodules, is it most likely a malignant tumor?
A clinical study of 60 patients with thyroid nodules (35 benign, 25 malignant) performed ultrasound examination and found:[1]
The detection rate of calcification in the malignant nodular group was 52%;
The detection rate of calcification in the benign nodule group was 25.7%.
It can be seen that thyroid nodules may appear calcified in both benign and malignant, but the calcification detection rate of malignant nodules is higher.
How is calcification formed?
Nodule calcification is usually deposited by carbonate or phosphate and other components, because of the new capillaries, thyroid epithelial cells excessive proliferation, etc., irregular calcium salt after a long period of deposition, and constantly by proliferating cells around, affected, and then gradually appear lesions. In addition, some scholars believe that the calcification of thyroid nodules is closely related to fibrous tissue hyperplasia, hindering the blood flow of thyroid follicles, causing ischemia, necrosis, and even cystic lesions of local thyroid tissues, and eventually developing calcification.
Note: Microcalcification is more dangerous than crude calcification!
Nodule calcification is usually judged by echo changes in ultrasound examination and is generally described as "strong echo". Calcifications also have a more granular classification, as follows:
Coarse calcification: strong echo in the ultrasonography of clumps or patches, accompanied by sound and shadow, and the diameter of the calcified nodules >2 mm;
Microcalcification: in the ultrasonic image map, there is a strong echo of gravel, needle tip and dot, the echo is weak, and the diameter of the calcified nodule ≤2 mm.
These two calcifications play a very important role in the identification of benign and malignant nodules. Multiple clinical case studies of calcified thyroid nodules have shown:
Benign nodules—mostly coarsely calcified
Thyroid epithelial cell proliferation is limited, and the deposited calcium salts are distributed in an orderly manner, and the edges are relatively clear, so they are mostly coarsely calcified;
Malignant nodules—mostly microcalcifications
Hyperproliferative cells are abnormally metabolically active and disordered, and there are many types of calcium salt deposits, mostly microcalcifications.
In addition, after refining the relationship between the classification of thyroid malignancies and calcification, the following results were obtained:
Papillary carcinoma and follicular carcinoma with low malignancy: the incidence of microcalcification is higher than that of crude calcification;
Medullary carcinoma and undifferentiated carcinoma with high malignancy: there was no significant difference in the incidence of microcalcification and crude calcification.
What should I do if nodule calcification is found? Need immediate surgery?
Although microcalcification of nodules suggests an increased likelihood of malignancy, further definitive diagnosis is required for surgical resection. Clinically, benign and malignant levels are often judged by biopsy puncture.
1
If the result is a benign nodule and is relatively small, it does not require treatment, and only needs to review ultrasound regularly every six months;
2
If the result is a malignant nodule, or if the nodule is large and compresses the surrounding tissue, surgery is required;
3
If the nodule is too small to be suitable for puncture biopsy, regular re-examination and close monitoring are recommended, as the peripheral blood vessels of the thyroid gland are abundant and there is a certain risk of surgery.
In addition to calcification, the following four conditions should also be vigilant
Ultrasound of malignant thyroid nodules is not only microcalcification, but also these features: unclear boundaries, irregular morphology, aspect ratio >1, low echo, blood flow disorders, cervical lymphadenopathy.
In particular, when the following four situations occur, you need to be vigilant against the possibility of malignancy:
Thyroid nodules are more than 2 cm in diameter, irregular in shape, not smooth on the surface, hard in texture and without tenderness;
Poor range of motion, substantial inactivity when swallowed;
Accompanied by hoarseness, difficulty breathing and other phenomena;
The thyroid nodules suddenly and significantly enlarge.
bibliography
Peng Guiping,Li Zhihui,Chen Zijian,Xu Suyin. Clinical application of ultrasound imaging characteristics of thyroid nodule calcification in the diagnosis of thyroid cancer[J].Modern Chinese Doctors,2021,59(36):105-108.