Thyroid Cancer
Overview
Thyroid gland is a small organ with a bridge-like structure called isthmus, which connects two lobes, located at the base of the anterior neck.
The thyroid gland produces hormones that regulate the metabolism of your body. The elevation of thyroid hormones (hyperthyroidism) are manifested by high heart rate, excessive sweating, heat intolerance, muscle weakness, overactive bowel and accelerated metabolism, such as tremor. Hypothyroidism, characterized by low thyroid hormones, is, as can be expected, characterized by a slowed down metabolism. While the thyroid gland regulates the body metabolism, the pituitary gland in our brain produces and secretes hormones that regulate the amount of hormones secreted by the thyroid gland.
Risk Factors:
Etiology of the thyroid cancer is not completely understood. Factors that increase the risk of thyroid cancer include being a woman, exposure to high radiation, and certain inherited genetic diseases.
Types:
Papillary cancer:
papillary cancer accounts for a substantial part of all thyroid cancers. They originate from follicular cells that produce hormone in the thyroid gland. It is usually benign in nature and the prognosis becomes poor, when it spreads to other organs of the body.
Follicular cancer:
It is the second most common type of the thyroid cancer. Quicker spread and higher risk of recurrence are remarkable properties.
Medullar cancer:
this type of thyroid cancer originates from C cells that secrete the hormone calcitonin in the thyroid gland. It can be detected at an early state due to elevation of calcitonin in blood. This cancer requires removal of the thyroid gland.
Anaplastic cancer:
although it is the least common type of thyroid cancer, it grows very quickly and the treatment is challenging. It is mostly seen in people aged 60 or older and removal of the gland may be necessary, as its quick growth makes breathing difficult.
Symptoms:
Thyroid cancer may not show any symptom at the early stage. Following symptoms can be manifested at advanced stages:
• A lump on neck
• Pain in throat and neck
• Hoarseness
• Difficulty swallowing
• Difficulty in breathing
• Enlarged lymph nodes in neck
• Prevention:
As is the case for all other cancers, prevention of thyroid cancer is also to eliminate or minimize manageable risks. Excluding radiation and genetic factors, the basic approach includes healthy lifestyle recommendations healthy nutrition, regular exercise and etc.), as the causes of thyroid cancer are not exactly known.
Thyroid cancer may develop in a part of thyroid nodules and therefore, thyroid examinations and screening are important. In the presence of these nodules, one should consult an endocrinologist as soon as possible.
Diagnosis:
If the physical examination and the imaging studies (CT, MRI, PET) that are ordered to investigate findings suspicious for thyroid cancer show a mass, provisional diagnosis is made. If family history is notable for thyroid cancer, genetic tests may be required to determine the risk of cancer. Blood tests may also give clues about the irregularities in the thyroid gland. The definitive diagnosis of the thyroid cancer requires biopsy.
Treatment:
After the diagnosis of thyroid cancer is made, the next step is to determine the stage. Your doctor will determine stage (I to IV) of your cancer based on a set of very strict criteria. You may think that thyroid cancer is very broadly staged as local, limited or regional and distant.
Generally cancer phases are symbolized with Roman numbers I to IV. The phase IV is the last phase and the most severe cancer. A personalized treatment is planned for each patient by considering stage, age, general health status and personal preferences.
For the thyroid cancer, the treatment options include chemotherapy, hormone therapy, iodine therapy, radiotherapy, targeted therapy and surgery. While these treatments are used to cure the tumor, they can be used to increase quality of life and to ease the severity of the symptoms in advanced stages. Moreover, the treatment options can be used together or alone.
Chemotherapy
Chemotherapy uses drugs to cure cancer. The active ingredients in these drugs kill cancer cells. Chemotherapy drugs can be administered intravenously or by mouth. If the drug is administrated through a vein, a thin tube, called a catheter, is inserted into a large vein and chemotherapy drug is delivered from this catheter throughout the course of the treatment.
One or more chemotherapy medicines may be administered according to the response of the cancer to the treatment and the type of cancer. After chemotherapy is given for a certain period, treatment is paused. After the completion of this defined “break” period, treatment resumes. Each of these periods is called cycle.
Targeted Therapy
Targeted therapies are newer anti-cancer treatments compared to chemotherapy. These medicines target specific abnormalities that are present in cancerous cells. Before these medicines are started, cancer cells are first analyzed in laboratories to determine whether they have particular mutations or not.
Radiotherapy
Radiation therapy aims to kill cancer cells by using high-powered energy beams.
If the radiation source is out of the body and beams are directed to cancer, this treatment is called external radiotherapy. On the other hand, if the radioactive agent is put into the area that cancer is present by a needle or catheter, method is called internal radiotherapy (brachytheraphy).
Although radiation therapy can also be used as first order therapy of cancer, generally it is used to kill cells that are not removed by surgery. In the first-line treatment, mostly radiotherapy and chemotherapy are administered together and this treatment is also known as chemoradiotheraphy. In advanced stage cancers, it plays an important role in relieving or removing the symptoms.
Surgery:
As a result of your surgeon's evaluation, your thyroid gland can be entirely removed (total thyroidectomy), or one lobe of the thyroid gland can be removed (lobectomy).
When the entire thyroid gland is removed (total thyroidectomy), you will need to use thyroid hormone pills in the rest of your life.
Your surgeon makes an incision on the neck base to expose the thyroid gland. Total thyroidectomy or lobectomy is performed according to the preoperative planning. In total lobectomy, thyroid tissue surrounding the parathyroid glands may not be removed. This approach is commonly referred to as near total thyroidectomy. No matter how much of the thyroid gland is removed, your surgeon removes the enlarged lymph nodes in the neck.
Asking your questions about the treatment of the thyroid cancer, your life after treatment, rehabilitation, pain management, clinical studies and all the questions in your mind about the thyroid cancer to your doctor will help you for an informed participation to your treatment and alleviating your concerns.
