CANCER AND THYROID NODULES
Thyroid nodules are very common. It is estimated that 5-10% of people may develop a palpable thyroid nodule. The frequency of thyroid nodules is higher in women and increases with age. Indeed, among women who are 55 years of age or older, nearly 60% have thyroid nodules. However, only a minority of thyroid nodules (about 5%) are carcinomas. Thyroid nodule evaluation, a relatively simple and standard procedure in clinical practice, can determine whether it is benign or malignant. While the clinical examination followed by imaging exams may be enough for some cases, a fine needle aspiration to obtain cytological material for analysis might be necessary for other patients.
The risc of cancer can be bigger in people with:
- Age below 20 years old or above 70 years old;
- Dysphagia or hoarseness presence;
- External radiotherapy story neck;
- Cervical lymphadenopathy presence;
MAPPING THE THYROID
The lump may be hipocaptante (cold), normocaptante (warm) or uptake (hot). Although cancer is more common in cold nodules, most cold nodules are not malignant, and even warm or hot nodules can be malignant in a lower percentage. Therefore it is not an essential test for the diagnosis of malignancy, but for the diagnosis of functional state of the node, in cases with laboratory test (TSH) changed.
It is the best imaging method for evaluating thyroid nodules. Using ultrasound can be seen the size and number of nodules, and their characteristics determine which nodes have more risk of malignancy and which deserve to be punctured.
FINE NEEDLE ASPIRATION PUNCTURE (FNA)
The most effective diagnostic method for thyroid nodules, to distinguish between malignant and benign. Requires experience of who reaps the exam and docitopatologista giving the result. The results in large series are benign in 70 to 75%, undefined or not diagnosis without 20 to 25%, and malignant about 5 to 10% of cases.
The treatment for nodules with cancer diagnosis by FNA is almost always surgical, except for some rare tumors such as lymphoma or anaplastic carcinoma. The incidence of false negative in FNA is small, so most patients diagnosed with benign nodule puncture can be followed clinically with reevaluation of the clinical picture, ultrasound to monitor the size and nodule puncture in periods ranging from 6 months 1 year. The patient should be part of the treatment decision and, in some cases, even benign tumors can be treated with surgery depending on size and clinical. Patients with indeterminate FNA result of the diagnosis or not can have the procedure repeated, and if there is still doubt, assess each case. Especially in cases of suspected malignancy surgery may be considered the best option.
In general, the BAF rarely needs to be performed in patients with autonomous node. The treatment of these patients may be surgery or radioactive iodine in cases of clinical or subclinical node (without symptoms, but with decreased TSH), to avoid risk of cardiac symptoms. Patients with hot nodules, but normal TSH can be followed clinically depending on the size of the nodule and patient choice.
With the advent of ultrasound, carotid doppler, some nodes are discovered accidentally. In this case can be followed clinically and with new ultrasound is small (less than 1 cm), or subjected to ultrasound-guided FNA is suspected malignancy, and treat according to the result.