10 questions and answers about thyroid
prof. dr. Bülent Çitgez answered the frequently asked questions about thyroid diseases and cancer during the Thyroid Awareness Week from 25-20 May.
1- Is every lump cancerous?
Thyroid nodules, usually detected incidentally during imaging or physical examination, affect half of the adult population. Despite the high prevalence, only 10-15% of thyroid nodules, which are usually asymptomatic, present as malignant tumors. What is important in the evaluation of thyroid nodules is applying patient-specific treatment of benign nodules and identifying malignant nodules that benefit from medical intervention, even if they are low risk.
2- What are the non-cancerous diseases of the thyroid gland?
The two main types of thyroid disease are hypothyroidism and hyperthyroidism. Both conditions can be caused by other diseases that affect thyroid function. Symptoms of hyperthyroidism include anxiety and irritability, hyperactivity, insomnia, fatigue, sensitivity to heat, muscle weakness, diarrhea, urinating more often than usual, feeling thirsty, itching, and sexual reluctance. Symptoms of hypothyroidism depend on the severity of the condition. Problems usually develop gradually over several years. Symptoms of hypothyroidism, such as fatigue and weight gain, are not easily recognized. However, as the metabolism continues to slow down, more obvious problems can arise. Symptoms of hypothyroidism include fatigue, cold intolerance, constipation, dry skin, weight gain, swollen face, hoarse voice, coarse hair and skin, muscle weakness, muscle pain, muscle tenderness and stiffness, menstrual cycles that are more severe or irregular than normal, hair loss, slowed heart rate , depression and forgetfulness.
3- How is a thyroid nodule detected?
Most thyroid nodules occur asymptomatically and are discovered incidentally during physical examination or other imaging procedures. Surgery may be needed for malignant or symptomatic nodules compressing nearby structures. For this reason, further investigations may be requested to determine whether treatment will be with medication or surgery. The preferred imaging modality for thyroid nodules is ultrasound, and ultrasound-guided biopsy with fine needle aspiration is the preferred tissue sampling. Cellular analysis is needed to better quantify the risk of one centimeter or larger nodules, suspicious-looking nodules on ultrasound, or malignant nodules. Preoperative biopsy and pathological diagnosis spare the patient the risk of a second operation.
4- What are the symptoms of thyroid cancer?
Most thyroid cancers do not cause any signs or symptoms in the early stages of the disease. As thyroid cancer grows, it can cause symptoms such as a palpable lump in the neck, a feeling that tight shirt collars are getting too tight, changes in your voice including increased hoarseness, difficulty swallowing, swollen lymph nodes in the neck, and sore throat and neck.
5- Does thyroid cancer spread throughout the body?
Thyroid cancer can sometimes spread to nearby lymph nodes or other parts of the body. Cancer cells that have spread can be detected at the time of initial diagnosis or during follow-up after treatment. The vast majority of thyroid cancers do not spread at all.
6- What is the treatment for thyroid cancer? Is chemotherapy necessary?
If the thyroid nodule is small and unilateral, the part with the nodule will be removed, while if there is a large thyroid nodule, the entire thyroid gland will be removed. Radioactive iodine treatment, radiotherapy, chemotherapy and targeted treatments, which destroy any cancer cells by entering the bloodstream after surgery, can be used in patients who need it. Chemotherapy is rarely used to treat thyroid cancer, but may sometimes be preferred for the aggressive and rare form of thyroid cancer that has spread to other parts of the body. The chemotherapy treatment process involves taking powerful drugs that kill cancer cells. It doesn’t cure thyroid cancer, but it can help manage symptoms.
7- Is Thyroid Cancer Genetic? What to do if thyroid is detected in the family?
There are significant differences between the types of cancer that occur in the tissues. Non-medullary thyroid cancer includes papillary, follicular, and anaplastic types. The vast majority of thyroid cancers, about 70% to 80%, are papillary thyroid cancers and are generally a non-aggressive and highly treatable form of the disease. Since most of these cases are rare or are not due to a clear genetic inheritance, genetic counseling or testing is recommended for anyone with a personal or family history of a single case of papillary thyroid cancer. Cowden syndrome occurs in familial, that is, genetically inherited conditions. Therefore, if a family member has thyroid cancer, ultrasound of the thyroid gland is recommended for other family members to detect it early. Thyroid cancer screening with ultrasound should also be performed in people with a family history of papillary thyroid cancer and a close relative. Type 2 (MEN2) associated with medullary thyroid cancer is a hereditary disease. All individuals with this type of thyroid cancer should be referred for genetic counseling and genetic testing offered. If a mutation in the RET gene is identified in a family, it is important to diagnose the condition in other family members so that they can benefit from conservative surgery (thyroidectomy). In general, patients can live long, high-quality, and active lives with proper drug therapy and follow-up after thyroid removal.
8- Is thyroid cancer less risky than other cancers?
The prognosis for most patients with thyroid cancer, ie how the disease will be affected in the future, is excellent. It means that thyroid cancer in general patients is not life-threatening and is treatable. However, in a small group of patients, the disease may be advanced.
9- Is there a connection between thyroid disease and weight?
Because basal metabolic rate is decreased in a person with hypothyroidism, an underactive thyroid is often associated with some weight gain. Weight gain is more common in people with more severe hypothyroidism. However, the decrease in basal metabolic rate due to hypothyroidism is usually much less dramatic than the significant increase seen in hyperthyroidism and results in smaller weight changes due to the less active thyroid. The cause of weight gain in a person with hypothyroidism is also complex and not always associated with excess fat deposition. Most of the extra pounds gained in individuals with hypothyroidism are due to excess salt and water accumulation. Weight gain is rarely associated with hypothyroidism. If the only presenting symptom of hypothyroidism is weight gain, it is less likely to be due to the thyroid alone. In hyperthyroidism, the body uses more energy than normal, which can lead to weight loss.
10- Does thyroid disease or cancer affect pregnancy?
People with active hyperthyroidism should take anti-thyroid drugs during pregnancy. Because these cross the placenta, they are prescribed in the lowest possible dose so that the baby is less likely to be affected. Radioactive iodine, another treatment for hyperthyroidism, should not be used during pregnancy. If hyperthyroidism is not controlled, it can increase the risk of miscarriage in the early stages of pregnancy. Therefore, expectant mothers who do not want to use drugs during pregnancy may prefer radioiodine treatment or surgery for Graves’ disease before pregnancy. If the dose of thyroid inhibitors is too high, the baby’s thyroid gland may become underactive and the baby may develop a goiter. For this reason, before the pregnancy plan, the use of medications should be regulated or discontinued under the supervision of a doctor. An untreated overactive thyroid carries a greater risk of pregnancy than taking thyroid-inhibiting medication. High blood pressure during pregnancy can lead to complications such as poor baby growth and premature birth. Thyroid function tests should be performed regularly during pregnancy to verify that the drug dose is appropriate.
If left untreated, hypothyroidism can lead to premature birth, low birth weight, and respiratory distress during pregnancy. Thyroid hormone therapy is used to treat a mother with hypothyroidism, and the dose of the drug depends on the individual’s thyroid hormone levels. In the first half of pregnancy, thyroid hormone levels should be checked every 4 weeks. Routine screening for all newborns includes testing for thyroid hormone levels.
If thyroid cancer is discovered during pregnancy, surgery can be expected in many patients after delivery, as the tumor spreads slowly. However, if the cancer is growing rapidly or has spread beyond the thyroid gland to the lymph nodes in the neck, surgery may be performed during pregnancy. The best time for this is the second trimester. While patients can undergo thyroidectomy with safe results in the first and third trimesters, this time frame is not ideal. Still recommended for treatment in case of aggressive disease