From other posts, you’ll be aware of the thyroid lesion (now 17x19mm) which I’ve been tracking since 2013. The surveillance has included routine thyroid blood tests, mainly TSH, T3 and 4. Due to trends in TSH and T4, it’s been suggested I’m borderline hypothyroidism. I’m out of range in TSH (elevated) but the T4 is currently at the lower end of the normal range. On 20 March 2018, following an Endocrine appointment, I was put on a trial dose of 50mcg of Levothyroxine to counter the downwards trend in results indicating hypothyroidism. Levothyroxine is essentially a thyroid hormone (thyroxine) replacement. One month after taking these drugs, my thyroid blood levels are now normal for the first time in 4 years (since there are records of test results – it might be longer).
The NET Connection?
To put things into context, hypothyroidism is an extremely common condition and the main treatment is administration of thyroid hormone replacement therapy (i.e. Levothyroxine). This is in the top 5 of the most commonly prescribed medication in USA and UK. Based on sheer numbers, it follows that many people are going to have an underactive thyroid whether they have NETs or not.
However, there are connections with NETs. Firstly there is one type of cancer known as Medullary Thyroid Cancer (MTC) and it also has a familial version known as Familial MTC or FMTC.
There are also connections between regular Neuroendocrine Tumours (NETs) and the thyroid. It can often be a site for metastasis, something I have not yet written off given it lights up on nuclear scanning – although my biopsy was inconclusive. You can see a summary of the connections and my own thyroid issue in more detail in my article “Troublesome Thyroids”. Please note the parathyroid glands are beyond the scope of this article.
Thyroid Function – the Lanreotide/Octreotide connection
Before I continue talking about hypothyroidism, here’s something not very well-known: Somatostatin analogues might cause a “slight decrease in Thyroid function” (a quote from the Lanreotide patient leaflet). The Octreotide patient leaflet also states “Underactive thyroid gland (hypothyroidism)” as a side effect. Many sources indicate that thyroid function should be monitored when on long-term use of somatostatin analogues. It’s also possible and totally feasible that many NET patients will have thyroid issues totally unrelated to their NETs. Remember, NET patients can get regular illnesses too!
What is Hypothyroidism?
Hypothyroidism is a condition in which your thyroid gland doesn’t produce enough of thyroxine. This leads to an underactive thyroid. It seldom causes symptoms in the early stages, but over time, untreated hypothyroidism can cause a number of health problems, such as obesity, joint pain, infertility and heart disease. Both men and women can have an underactive thyroid, although it’s more common in women. In the UK, it affects 15 in every 1,000 women and 1 in 1,000 men. Children can also develop an underactive thyroid.
What causes Hypothyroidism?
- Autoimmune thyroid disease sometimes called Hashimoto’s thyroiditis
- Radioactive iodine or surgery to correct hyperthyroidism or cancer
- Over-treatment of hyperthyroidism with anti-thyroid drugs
- Some medicines
- A malfunction of the pituitary gland
What are the symptoms of Hypothyroidism?
The signs and symptoms of hypothyroidism vary, depending on the severity of the hormone deficiency. But in general, any problems you have tend to develop slowly, often over a number of years. At first, you may barely notice the symptoms of hypothyroidism, such as fatigue and weight gain, or you may simply attribute them to getting older. But as your metabolism continues to slow, you may develop more-obvious signs and symptoms. Hypothyroidism signs. Below are major symptoms associated with hypothyroidism:
- Weight gain or difficulty losing weight (despite reduced food intake)
- Coarse, dry hair and dry skin
- Hair loss
- Sensitivity to cold
- Muscle cramps and aches
- Memory loss
- Abnormal menstrual cycles
- Decreased libido
- Slowed speech (severe cases)
- Jaundice (severe cases)
- Increase in tongue size (severe cases)
You don’t have to encounter every one of these symptoms to be diagnosed with hypothyroidism. Every patient’s experience with the disorder is different. While you may notice that your skin and hair have become dry and rough, another patient may be plagued more by fatigue and depression.
When hypothyroidism isn’t treated, signs and symptoms can gradually become more severe. Constant stimulation of your thyroid gland to release more hormones may lead to an enlarged thyroid (goiter). In addition, you may become more forgetful, your thought processes may slow, or you may feel depressed.
Now ….. some of these symptoms look very familiar to me and they also look very familiar to some of the comments I see on patient forums related to somatostatin analogues and some of the NET syndromes – that jigsaw thing again. I guess it’s possible that people are borderline hypothyroidism prior to taking somatostatin analogues and the drug pushes them out of range (similar to what it’s known to do with blood glucose levels and diabetes). I’m not suggesting a direct clinical link in all cases but what I am suggesting is that perhaps some of the answers might be found in checking Thyroid hormone levels.
What are the Thyroid Hormone tests for Hypothyroidism?
A high thyroid stimulating hormone (TSH) level with a low thyroxine (T4) level indicates hypothyroidism. Rarely, hypothyroidism can occur when both the TSH and T4 are low. A slightly raised TSH with a normal T4 is called subclinical, mild, or borderline hypothyroidism. Subclinical hypothyroidism can develop into clinical or overt hypothyroidism
Routine ‘Thyroid blood tests’ from your doctor will confirm whether or not you have a thyroid disorder. I now test for TSH (thyroid-stimulating hormone), T4 every 6 months. Mostly in range but recently TSH is spiking out of range and T4 is consistently at the lower end of normal range.
Can hypothyroidism be treated?
Yes. A synthetic version of thyroxine taken daily as prescribed. e.g. Levothyroxine tablets
OK that’s Hypothyroidism – what is Hyperthyroidism?
Hyperthyroidism is a condition where the thyroid gland produces too much thyroid hormone for the body’s needs. It is also known as an overactive thyroid or thyrotoxicosis. An overactive thyroid can affect anyone, but it’s about 10 times more common in women than men and it typically starts between 20 and 40 years of age.
- Hyper – means “over -“
- Hypo – means “under -“
- The terms “hyperthyroid” and “thyrotoxic” are interchangeable
- Graves’ disease – the most common cause
- A toxic nodular goitre (a goitre is an enlarged thyroid gland)
- A solitary toxic thyroid adenoma (an adenoma is a clump of cells)
- Thyroiditis (infection or inflammation of the thyroid gland) which is temporary
A speeding up of mental and physical processes of the whole body, such as
- weight loss, despite an increased appetite
- palpitations / rapid pulse
- sweating and heat intolerance
- tiredness and weak muscles
- nervousness, irritability and shakiness
- mood swings or aggressive behaviour
- looseness of the bowels
- warm, moist hands
- passing larger than usual amounts of urine
- an enlarged thyroid gland
If the cause is Graves’ disease, you may also have ‘thyroid eye disease’. Smokers are up to eight times more likely to develop thyroid eye disease than non-smokers.
- By a physical examination and blood tests
- A low thyroid stimulating hormone (TSH) level with a high thyroxine (T4) level indicate hyperthyroidism
- Antithyroid drugs
- Surgery to remove all or part of the thyroid gland
- Radioactive iodine to destroy most of the thyroid tissue
Research sources used to compile this post:
1. Lanreotide Patient Leaflet.
2. Octreotide Patient Leaflet.
Thanks for reading