All goitres are not thyroid Cancers but “Do Not Neglect Thyroid Nodules”
Authored by Dr. Prabhat Yaji, Consultant Surgical Oncologist and , Head and Neck Surgeon, BGS Gleneagles Global Hospital, Bengaluru
What is thyroid?
Thyroid gland is an endocrine gland located in the lower neck below the Adams apple and above collar bones. Thyroid gland secretes hormones which are essential for metabolic activity and also growth and development of our body and brain.
Any enlargement of the thyroid gland is called as Goitre. Any lumps arising from the thyroid gland is called as thyroid nodule. They can arise as a single nodule which is called solitary thyroid nodule or nodules may be multiple which is called as multi-nodular goitre. According to an American Thyroid Association dataabout 50 percent of people above 60 years have thyroid nodules; and the incidence of thyroid nodule is about 70 percent in women above 60 years and fortunately about 90 percent of them are benign, meaning they are not cancerous.
Causes of Goitre:
There are various causes of goitre and not all causes are known. Thyroid enlargement is seen in pregnancy when the expectant mother’s body requirement of thyroid hormone increases. Most common cause of goitre has been due to iodine deficiency goitre which is called as endemic goitre. It is common in the sub Himalayan regions in the North India which is also called “goitre belt”and many studies have shown that the soil in the subcontinent is deficient in iodine. The incidence of endemic goitre has reduced drastically in the last three decades because of universal iodination of the salt. The other common causes include colloid nodules andthyroid adenomas, autoimmune condition called Hashimotos thyroiditis, and some less common causes are adenomatous hyperplasia and thyroid cyst. These conditions may also be associated with overproduction of thyroid hormones called as hyperthyroidism or underproduction of hormones called as hypothyroidism. It is very much important to treat hyper or hypothyroid and its symptoms with appropriate medications.
Among the thyroid nodules only about 5- 15 % are cancerous nodules. It is important to differentiate the cancerous nodule from non-cancerous nodules. It is especially significant in India because about 5 crore of our population have goitre. It has also been reported that there an increase in incidence of thyroid cancers among Southern India.
Diagnosis and treatment:
Thyroid cancers generally presents without any symptoms apart from thyroid nodule. Some patients can have hoarseness of voice or multiple lumps in the neck. The presence of cancer can be detected with Ultrasound scan of neck and a simple needle test called as Fine needle aspiration cytology(FNAC). The common variety of thyroid cancers which constitutes about 95 % of all thyroid cancers are papillary and follicular cancers are almost always curable with surgery alone or surgery along with radioiodine therapy. Some uncommon types of thyroid cancers like medullary and anaplastic cancers are generally aggressive and achieving cure may not be possible among these patients. Fortunately, they constitute only about 5% of all thyroid cancers.So, anyone with thyroid nodule or any suspicious lump in the neck should seek medical advice and undergo appropriate tests as advised. It is always advisable to seek specialist advice on regular basis as long standing non-cancerous thyroid nodules may turn cancerous over a period of time. An expert will always have an index of suspicion if the nodule increases in size rapidly or appearance on new lumps in thyroid or in neck.
Thyroid cancers are curable with 5 year survival of 98% and 20 year survival above 90%.There is a popular adage among oncologists “If I am cursed with cancer and given a chance to choose my cancer, I will choose Thyroid cancer.”