(Last Updated On: July 23, 2009)
In my last two Gimp posts, I discussed the fact that I need to have a Thyroid Lobectomy due to a suspicious tumor located in the left lobe of my thyroid. I also wrote about how the thyroid works and what it does for the body. In this blog entry, I will discuss thyroid nodules, thyroid cancers, and what happens after thyroid surgery.
Thyroid Nodules refer to some sort of growth in the thyroid that is not actual thyroid tissue. This could include cysts, benign tumors and malignant tumors. Thyroid nodules are actually quite common and the chances that someone has a nodule increases with age. Fifty percent of 50-yr olds will have at least one thyroid nodule. By the time the individual is 70 years old, the chance increases to 70%. However, it seems that thyroid nodules are about three times more common in women than men. About one in every 12 or 15 young women have a thyroid nodule compared to one in 40 young men.
Does a Thyroid Nodule Mean Cancer?
Thyroid Nodules are usually not cancerous. In fact, the chances of them being cancerous is quite rare. Some reports show that less than 1% of thyroid nodules are cancerous. Many small thyroid nodules go undetected and some people will never know they even have a nodule. But, bigger nodules are usually more noticeable and have a higher chance of being cancerous. If a thyroid nodule is detected, endocrinologists usually opt to perform a biopsy to sample the cells to determine whether the nodule is benign or malignant.
Though thyroid cancer is rare, it does happen. However, it is one of the most treatable cancers. Most thyroid cancers don’t easily metastasize (spread into other organs), especially if the malignant tumor is removed before it grows too large.
The most common type of thyroid cancer is papillary. About 78% of thyroid cancers fall under this category. Approximately 17% of thyroid cancer cases are follicular or Hurthle cell. And then the remaining cases generally fall under medullary or anaplastic. 97% of papillary and follicular cancers are “cured” when treated. However, anaplastic cancer, though extremely rare, is the most aggressive and has a low cure rate.
Hurthle cells are a cell that looks bigger than a follicular cell and stains pink. My biopsy came back with a high level of Hurthle cells. Hurthle cells are a bit ambiguous because they can be present in both benign and malignant tumors. Reports vary in this respect, saying somewhere between 13 and 67% of tumors containing Hurthle cells are malignant. This is a huge spread! However, it seems that malignancy occurs more often in larger tumors. About 80% of tumors that are 4 cm or larger will be malignant. Tumors that are about 2 cm in size (which mine is) have a much lower chance of being cancerous.
Generally, a biopsy will not determine whether a tumor with Hurthle cells is malignant or benign. Instead, the whole tumor needs to be looked at to determine how Hurthle cells are actually behaving in the tumor. According to emedicine.com, whether this kind of tumor is benign or malignant “is based on vascular invasion and/or capsular invasion, as well as on permanent histologic sections or extrathyroidal tumor spread and lymph node and systemic metastases.” Basically, this requires that the whole tumor be removed to take a look at the behavior of the cells. Benign Hurthle cells do not generally come back once they are removed.
Follicular or Hurthle Cell Cancer
Follicular cancer is often lumped together with Hurthle Cell cancer into the same category, though they are actually a little different.
Follicular cancer is considered to happen in about 15% of thyroid cancer cases. It is more aggressive than the more common papillary cancer and has about an 8-13% of spreading to the lymph nodes. This particular type of cancer seems to be more aggressive as the age of the patient increases, with a definite difference occurring in patients over 40 years of age than under 40. The ability for this cancer to be cured depends on early detection. If it has not spread into the vascular system, it is highly curable.
Hurthle cell cancer is about 1/4 as common as follicular cancer and happens in about 4% of thyroid cancer patients. This cancer tends to occur in older patients, with the median age being 55 yrs. Hurthle cell cancer tends to be a bit more aggressive than follicular cancer, with about 10-33% chance of metastasizing. Like follicular cancer, the curability of Hurthle cell cancer depends on the extent of vascular invasion. Like most thyroid cancers, this seems to be related to the age of the patient and size of the tumor. Vascular invasion is seen more often in older patients. Generally, 75% to 90% of the cases are curable.
If My Tumor is Found to be Benign
If my tumor is found to be benign, I will have only half of my thyroid removed. Though the likelihood for the Hurthle cells to return is low, I will likely stay on Thyroxine for thyroid hormone replacement therapy. The idea behind this is that this will keep my thyroid from working too hard and will help prevent new tumors from forming. However, I will not be dependent on this medicine. My thyroid will still be working. If necessary, the remaining half of the thyroid will take over the full function of the whole thyroid.
If My Tumor is Found to be Malignant
If my tumor is found to be malignant, then I will need to have my whole thyroid removed. The chance that malignant Hurthle cells will return is much higher than benign Hurthle cells. This is why they whole thyroid gland is removed. It is possible, not not common, for the malignant Hurthle cells to return in other organs around the thyroid once the thyroid is removed. Generally, chemotherapy is not used to treat this kind of cancer unless vascular invasion is extensive.
After having my whole thyroid removed, I will be dependent on the synthetic hormone Thyroxine.
How does synthetic Thyroxine Work?
Thyroxine is a type of hormone that is produced by your thyroid, also called T4. Thyroxine in synthetic form (taken as a medication) is often called Levothyroxine, Synthroid, or Levoxyl. There are different levels of thyroxine which can be prescribed by a doctor. I currently am taking 88 mcg per day for thyroid hormone replacement therapy. However, if my whole thyroid is removed, I will likely be bumped up to 125 mcg.
As a reminder, T4 is used by your body to regulate metabolism. T3, also produced by the thyroid, has about 4 times the power of T4 in regulating metabolism. So, why are people without thyroids only prescribed T4 (Thyroxine) and not a T3 drug? Well, it’s because your body can do amazing things! A person without a thyroid can take synthetic T4 and the body will use that to produce. This will happen in the liver and kidneys, assuming these organs have enough cortisol. If not, a synthetic drug that has T3 in it can be taken. It is commonly called Cytomel or Liothyronine. However, if you can get your body to produce the needed about of T3, this is always better than a synthetic option.
In a Nutshell
Yes, my biopsy came back with Hurthle cells- a lot of them. But, given my age and the size of the tumor, it is not highly likely that the tumor is cancerous. Still, it’s better to know, I think, than to not know. It’s better to catch a cancerous tumor before it spreads to the lymph nodes than after. This is why I’m having the thyroid surgery.