Thyroid microcarcinoma
Introduction
Introduction to thyroid microcarcinoma The thyroid microcarcinoma is used to describe cases in which the thyroid gland does not reach an abnormal mass, and in the cervical lymph nodes, the thyroid cancer nodule with a tumor diameter of 1.0 cm is a thyroid microcarcinoma. basic knowledge The proportion of illness: 0.005% Susceptible people: no special people Mode of infection: non-infectious Complications: upper laryngeal nerve injury respiratory infection
Cause
Causes of thyroid microcarcinoma
(1) Causes of the disease
Currently there are no related content description.
(two) pathogenesis
The pathological type of most TMC is papillary carcinoma, so some people call it papillary microcarcinoma, but there are other pathological types. Baudin reports that 87% of papillary carcinoma of TMC, and 12.1% of follicular carcinoma, Noguchi report In the case of cases, follicular TMC accounted for 4.2%, medullary carcinoma accounted for 0.27%, and the rest were papillary or nipple follicular mixed TMC. No undifferentiated carcinoma was found. In the case of the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, papillary Accounted for 86.4%, follicular form accounted for 12.7%, and only one case was medullary carcinoma. It is worth noting that in recent years, reports of small medullary carcinoma have increased. Henry reported 11 cases of subclinical micromedullary carcinoma, Peix (2000). Reported 20 cases of small medullary carcinoma. In general, the pathological type of TMC is mostly differentiated thyroid cancer. In addition, during the operation or pathological examination, attention should be paid to the presence of multiple cancerous lesions. Some TMC cases have multiple cancerous lesions. The incidence of multiple TMC is reported to be 9.5% to 40%. C-cell hyperplasic (CCH) is a non-invasive proliferative response of thyroid C cells. In medullary carcinoma, the increase in CCH has been used as a difference in sporadic and residual Histological markers of medullary carcinoma, FNAC examination found that CCH contributes to the diagnosis of medullary carcinoma, CCH can be divided into focal, diffuse, nodular and neoplastic, neoplastic C cell proliferation can suggest the marrow The presence of cancer.
Prevention
Thyroid microcarcinoma prevention
There is no effective preventive measure for this disease. Early detection and early diagnosis are the key to the prevention and treatment of this disease.
Complication
Thyroid microcarcinoma complications Complications, laryngeal nerve injury, respiratory infection
First, postoperative bleeding of thyroid cancer is the most intensive surgery after the transfer of Chinese medicine treatment. Mainly caused by incomplete or imperfect hemostasis or due to ligature detachment. Postoperative cough, vomiting, over-frequency activity or conversation is also a cause of bleeding.
Second, recurrent laryngeal nerve, laryngeal nerve injury is a transfer of Chinese medicine after important surgery in thyroid surgery. Mainly caused by inadvertent operation, traction or hematoma compression nerve or direct contusion.
Symptom
Thyroid microcarcinoma common symptoms bone metastasis gland nodule lymph node degeneration neck lymph node enlargement cystic necrosis neck cystic lesion goiter
The clinical manifestations of TMC are basically the same as those of thyroid cancer, but the lesions are small. If you do not pay attention to careful examination, it is often difficult to find.
1. The thyroid gland can touch the tiny nodules, the quality is hard, the activity is good, and there is no tenderness. Because the nodules of TMC are generally small, they are located in the thyroid gland or even the capsule. It is often difficult to find the palpation without careful examination. Noguchi Of the 867 reported cases of TMC, only 23 (2.7%) were clinically accessible to glandular nodules.
2. If a multinodular goiter is combined, it should be noted that there are no small or hard nodules in many nodules of different sizes. This nodule is different from the surrounding goiter nodules. Carefully palpate the bilateral lobes, do not only pay attention to the thyroid leaves on the obvious side of the nodule, but ignore the contralateral lobes that are not obvious.
3. TMC often has cervical lymph node metastasis. The incidence of cervical lymph node metastasis in TMC is between 2.0% and 43%. Some cases have cervical lymph node enlargement, which is the earliest clinical manifestation of TMC. Development may be rapid and cystic necrosis and lymph node degeneration, many cervical lymph node metastasis can be misdiagnosed as cystic lesions of the neck or bronchogenic cysts.
4. Distal metastases, such as spine, bone and lung metastases, can occur, but the incidence is extremely low. In some cases, bone metastases may become the first manifestation.
Examine
Examination of thyroid microcarcinoma
1. TGAb, TPOAb detection of thyroid function is mostly normal, thyroid autoantibody TGAb, TPOAb is generally normal.
2.131I uptake rate function is normal.
3. Serum calcitonin and calcitonin levels are elevated, if necessary, can be used as a pentapeptide gastrin stimulation test, positive suggestion of medullary carcinoma may be.
4. Fine needle aspiration cytology The development of FNAC technology has greatly improved the preoperative diagnosis rate of TMC. The data from Mayo Hospital in the United States indicate that 70% of TMC diagnosis is based on surgery before FNAC is introduced into the clinic. After the introduction of FNAC in the 1980s, FNAC accounted for 40% of cases diagnosed with TMC, while cases found by surgery fell to 20%.
FNAC is mainly useful for the diagnosis of nodules in two sites. One is the cervical lymph nodes. The presence of TMC can be confirmed by FNAC for cervical lymphadenopathy. The second is for the nodules near the capsule, which are accessible to the body. Can identify the nature of nodules. For TMC nodules <1cm in diameter, the proportion of FNAC found under B-ultrasound is more than 50%. There is no false positive report in B-guided FNAC examination, the false negative rate is about 12%, and the relative sensitivity is diagnosed. 60% to 90%, specificity 100%, positive predictive value 100%, negative predictive value 80%, accuracy rate up to 85%.
5. Frozen pathological sections, such as suspicious hard nodules found during surgery, can be confirmed by rapid frozen section, but there is a certain false negative rate, affected by specimen selection and sliced parts, the surgeon should carefully check the thyroid double Glandular lobes, for the hard and suspicious small nodules, should be cut and sent to the frozen section, and the pathologist should carefully select the suspicious nodules for cryosection in the resected specimen.
6. B-ultrasound TMC diagnostic compliance rate is less than 15%, especially gland examination of multiple nodules is often difficult to distinguish which nodule is TMC nodules, tiny nodules <0.5cm in diameter, B-ultrasound is often difficult to find, Moreover, in many cases, the nodules detected by B-ultrasound were not TMC nodules. Of the 110 cases summarized by the First Affiliated Hospital of Zhongshan University in Guangzhou, only 13 cases (12.0%) had preoperative B-ultrasound diagnosis of TMC.
7. CT, MRI examination has a low diagnostic compliance rate for TMC.
8. Nuclide scans can show cold or cold nodules for larger nodules, but in most cases, especially nodules <0.5 cm in diameter are difficult to detect.
Diagnosis
Diagnosis and diagnosis of thyroid microcarcinoma
Due to the small primary nodules of TMC, clinical palpation is difficult. Many cases have lymph node metastasis, distant metastasis, or biopsy of metastatic lesions, or biopsy before diagnosis. More cases may be In the operation of other thyroid diseases, the suspicious microcarcinoma nodules removed, frozen section examination, or postoperative paraffin section examination confirmed the diagnosis. Because the cancer nodules are small, the diagnostic rate of imaging examination is low.
