Thyroid nodules are very common, and through proactive intervention at multiple levels of diagnosis, treatment and follow-up, malignant nodules can be diagnosed early and given standardized and reasonable treatment at an early stage, which can achieve complete cure or greatly prolong survival time, and also enable a large number of benign patients to avoid over-treatment and reduce medical costs and waste of medical resources for the whole society. The following is a brief introduction to thyroid nodules, which I hope will be helpful to you.
1. What is a thyroid nodule: a scattered lesion caused by abnormal local growth of thyroid cells, which can be tumorigenic or a non-tumorigenic abnormality, usually benign, but can also be malignant. The detection rate with the help of high-resolution ultrasound can be as high as 20%-76%; 5%-15% of them are malignant.
2.The evaluation process of thyroid nodules.
(1) Physical examination and related history taking: history of head and neck radiation exposure; history of thyroid cancer in first-degree relatives; history of radioactive dust exposure under 14 years old; nodules larger than 4 cm, rapid growth, hard texture, fixed adjacent structures, local lymph node enlargement, hoarseness, dysphagia, local pain and distant metastasis; all the above conditions increase the risk of malignancy.
(2) Laboratory tests: all thyroid nodules should be tested for serum TSH levels; if TSH is abnormal, T3 and T4 can be further tested; if necessary, thyroid-related antibodies (TR-Ab, TPO-Ab, TG-Ab) and thyroglobulin and calcitonin can be tested.
(3) Ultrasound-based imaging: High-resolution ultrasound is the preferred method for evaluating thyroid nodules; the key to ultrasound evaluation is to screen out suspicious nodules and perform further cytologic examination (FNAB); all thyroid nodules should be examined by neck ultrasound; suspicious signs on ultrasound are: blurred borders, 49.7% incidence of malignant nodules; irregular margins, 82.5% incidence of malignant nodules; and a high incidence of specific nodules. 82.5% incidence and 74.3% specificity; A/T ≥ 1, diagnostic specificity up to 81.5%-92.5%; absence of acoustic corona, or uneven thickness, incomplete; hypoechoic or ultra-hypoechoic (lower than the echo of the zonule); microcalcifications, specificity up to 75.6%-94.4%; central blood supply; RI ≥ 0.75, diagnostic accuracy of 91% and specificity of 97% for cancer (4) Cytological examination
(4) Cytological examination; the most commonly used is FNAB (fine needle aspiration biopsy); it is the most sensitive and specific method to assess the benignity and malignancy of thyroid nodules; it is also the most cost-effective method; FNAB under ultrasound guidance can improve the success rate of sampling and diagnostic accuracy;
3, what kind of nodules do not do FNAB: simple cystic nodules; intra-nodal spongy nodules (multiple microcysts account for >50% of the nodules); serum TSH is reduced and nuclear examination is “hot nodules”; nodule diameter <10mm, no suspicious family history or suspicious malignant signs.
4. Possible risks of FNAB: Failure of puncture: too little material may not be available for diagnosis or the specimen may not be sufficient for diagnosis; stress and painful stimulation may cause arrhythmia, syncope, elevated blood pressure and cardiovascular accidents; bleeding or formation of local hematoma at the puncture site may compress the trachea; injury to the trachea and lung tip may cause cough, pneumothorax and dyspnea; injury to the nerves may cause In case of malignant tumor, puncture may lead to tumor implantation and metastasis; in case of inflammation, puncture may lead to the spread of inflammation and abscess formation.
5. Limitations of FNAB report: There are four kinds of results for diagnosis or report.
Undiagnosable; about 20%, mostly due to sampling reasons
benign; about 50-70% of cases
Malignant; about 5%.
Uncertain/suspicious; about 20-25%, cell damage, follicular hyperplasia cannot be excluded, and PTC is suspected.
6. Diagnostic value of FNAB for thyroid cancer.
USA Nodal surgery rate Surgical nail cancer detection rate
1980 89.9% 14.7%
1993 46.6% 32.9%
7. Clinical management of benign thyroid nodules.
(1) Regular follow-up is the main focus: ultrasound and serum TSH are repeated at 6-18 months; US-FNAB must be repeated if features of clinical or ultrasound suspicion of malignancy are present.
(2) Conventional L-T4 therapy is not recommended.
(3) Indications for surgery: local compression symptoms clearly associated with the nodule; history of previous external radiation; progressive nodule growth with ultrasound features suspicious of malignancy; cosmetic needs.
(4) PEI, RFA, 131I.