Thyroid cancer

Thyroid cancer is curable when diagnosed and treated accurately. The treatment varies because there are four major types of thyroid cancer.  

What is thyroid cancer?

Thyroid cancer occurs when cells in the thyroid gland undergo genetic changes (mutations). Thyroid cancers are usually seen as a lump that can be felt through the skin on the neck or as a nodule in the thyroid gland. The nodule may vary in size - from a small pea to that a walnut. Constituted by cells arranged in groups, nodules can be classified as cold or hot. The nodule type that must be taken seriously is not the hot one but the cold one, because of the fact that 15 per cent of this type can be cancerous. Therefore, patients who have cold nodule must undergo needle biopsy without delay. For the best results, biopsy should be performed by specialists working in specialized health care facilities and should be examined under microscope by cytology or pathology experts, working at the same health care facilities. The reason to perform biopsy is to determine whether the nodule is cancerous or not.

Types of thyroid cancer and its treatment

There are four major different types of cancer in the thyroid gland:

1. Papillary thyroid cancer:

The papillary type of thyroid cancer is the most common, making up about 80 percent of all thyroid cancer diagnoses. Papillary thyroid is mostcommonly diagnosed in people between the agesof20 and50. Gender-wise, women are three times more likely to contractthis form of cancer. It is the mostcommon thyroid cancer in children aged 14 years or younger. The cancermay not display any symptoms formany years (sometimes for 30 years) because the tumor stays usuallyunder 1 cm in diameter and may thennever grow. This cancer is usually noticed incidentally while the glandis removed in surgeries due to goiteror hypothyroidism. 2 per cent of the Turkish population suffers from thistype of cancer. Additionally, peoplemay not even be aware that they have this cancer. In some countries such asJapan and Finland, the rate can be ashigh as 30 per cent. It is believed that the high consumption of various typesof seafood is the reason for this highrate. The excessive intake of iodine causes inflammation in the thyroidgland and this causes cancer.However, determination of the nodules during check up programs has improved in the recent years thanks to highly sensitive ultrasound equipments

Treatment:  It is treated with surgery. The entire thyroid gland is removed (total thyroidectomy). After the surgery, if the patient has a “microcancer” smaller than 10 mm, then they will take only thyroid hormone medication. In case the cancer has spread to the lymph nodes and has reached the capsule that surrounds the thyroid cancer, as well as in cases the cancer’s diameter is bigger than 10 mm, the patient should undergo radioactive iodine treatment for six weeks after the surgery. This treatment reduces the risk of both local recurrence and distant metastases. In cases lymph node involvement is developed on the patient’s neck, the thyroid should be removed together with the lymph nodes. If such a case is suspected before the surgery, then the lymph node is not removed by any means. At this stage, the diagnosis is made with needle biopsy and the patient’s thyroid gland and lymph nodes are removed by preserving the tissue integrity. This surgery is called total thyroidectomy + modified radical or functional neck dissection. The follow-up is performed with the TSH and thyroglobulin levels. TSH shows the amount of hormone received by the patient and the thyroglobulin level, which should be around “0” after the treatment and helps detecting a recurrent disease. However, in some cases the disease may reappear without a high level of thyroglobulin. 90 per cent of the patients return to their normal life after the treatment.

2. Follicular thyroid cancer: This cancer typically occurs in women aged between 40 and 60. They constitute 10 per cent of the thyroid cancer cases. Among the thyroid cancers, follicular thyroid cancer is the hardest to diagnose. It is impossible to understand whether the lesion is a cancer or not, both by needle biopsy (performed before the surgery) and by the frozen section evaluation (performed during the surgery). It is not possible to understand whether the patient has cancer or not, it must be observed if the cells invade the capsule which surrounds a lump that consists of normal cells. When the capsule is invaded the tumor is diagnosed as follicular thyroid cancer and when the capsule is not invaded, it is diagnosed as benign follicular thyroid.

Treatment: As in papillary thyroid cancer, the treatment for this cancer is total thyroidectomy and regardless of the size of the invading cancerous tumor, it is treated with radioactive iodine treatment following the surgery. 80 per cent of the patients continue their normal healthy life after the treatment.

3. Medullary thyroid cancer:

Medullary tumors account for 5 per cent of all diagnosed thyroid cancer tumors. While the “familial type” (which means that the thyroid cancer is passed genetically through a family), is observed between the ages of 1 and 20, the non-hereditary type is observable after the age of 40 and usually appears as lymphatic metastasis.

Treatment: The treatment is total thyroidectomy plus lymph node dissection in the side of the tumor is. There is no need for radioactive iodine treatment after this surgery because the cell, which is different than other thyroid cells, cannot keep the iodine. During the follow-up, the calcitonin level in the blood is checked. 60 per cent of the patients continue to live healthy lives after successful treatment.

4. Anaplastic thyroid cancer

This type constitutes 5 per cent of all thyroid cancers. Anaplastic thyroid cancer is more common in older people (with an average age of about 60). Papillary or follicular cancers untreated for many years abruptly change their biological behaviors and start to grow quickly. This causes anaplastic thyroid cancer. In such cases, surgery is not an option. However, treatment with radiation therapy is used to make breathing easier in those patients who are suffering from shortness of breath.

What is goitre?

There are 3 diseases caused by the thyroid gland: goiter, thyroid cancer and thyroiditis. Goiter is the most common among the thyroid diseases. Researches show that 60 per cent of the population has early-stage goiter. It is a fact that 30 out of 100 people in Turkey have a risk of goiter. Gender is also an important factor in the incidence of this disease. In terms of gender distribution, women are five times more likely to get the condition.

The thyroid can grow as one or more nodules in volume. “Nodular goiter” is the medical term. It is known that the factor causing goiter is the lack of iodine.

What are the diagnostic methods?

In small goiters, the diagnosis is performed by hand by feeling the neck and then by blood tests measuring T3, T4, TSH levels and by thyroid scintigraphy tests. The growth of the thyroid gland may cause a fist-sized swelling at the base of the neck. This situation is known as “nodulation”. Nodulation can appear in the coming years among patients who had not been treated accurately and with modern means. The rate of cancer in nodules is 5 per cent. However, 95 per cent of patients who suffer from thyroid cancer continue their normal life.
If a person thinks they have goiter, they must consult an endocrinologist, i.e. a specialist who deals with hormones. To tackle the disease, team work is required, as after the ultrasonographic examination of the radiologists (which is carried out after the physical examination), a needle biopsy (by taking a piece and interpreting it) may be needed. Patients diagnosed with cancer as a result of a “fine needle aspiration biopsy”, used in the diagnosis of thyroid nodules, are being operated. Surgery is also recommended for patients who are suffering from shortness of breath due to a nonmalignant nodule on their neck.