how radiation can cause thyroid disorders

In Sep, the test result showed my TSH (Thyroid Stimulating Hormone) reading was quite high. I had to do another blood test in Oct to confirm the result. Today, my oncologist's assistant reviewed this 2nd result with me. It showed my TSH reading had increased further. The result confirms I am hypothyroid.

What is hypothyroidism? Doctors normally don't spend time explaining illnesses to patients. So I went to the internet to find out more.

Hypothyroidism is an underactive thyroid gland. Hypothyroidism means that the thyroid gland can’t make enough thyroid hormone to keep the body running normally. People are hypothyroid if they have too little thyroid hormone in the blood. Common causes are autoimmune disease, surgical removal of the thyroid and radiation treatment.

Radiation used to treat cancers of the head and neck can affect the thyroid gland and may lead to hypothyroidism. Thyroid problems are common in cancer survivors who had head or neck radiation.

Read on if you want to know more about thyroid disorders. Women are 8 times more likely than men to suffer from thyroid problems.

What is the role of our thyroid gland? The thyroid gland is located in the front of the neck just below the larynx (voice box). It secretes hormones that control the body's metabolism. These hormones are thyroxine (T4) and triiodothyronine (T3). The secretion of T3 and T4 is controlled by the pituitary gland which is part of the brain.

The pituitary gland makes a chemical called thyroid-stimulating hormone (TSH) which travels in the blood stream to the thyroid. TSH stimulates the thyroid gland to make the thyroid hormones, T3 and T4. When levels of T3 and T4 are low, the brain increases the production of TSH which in turn tries to make the thyroid gland produce more T3 and T4. Conversely, if the level of either T3 or T4 is too high, the brain senses this and decreases the production of TSH which leads to less production of T3 and T4.

When thyroid hormone levels are too low, the body’s cells can’t get enough thyroid hormone and the body’s processes start slowing down. As the body slows, you may notice that you feel colder, you tire more easily, your skin is getting drier, you’re becoming forgetful and depressed, and you’ve started getting constipated.

There is no cure for hypothyroidism, and most patients have it for life. You have to make a lifetime commitment to treatment. If you take your pills every day and work with your doctor to get and keep your thyroxine dose right, you should be able to keep your hypothyroidism completely controlled throughout your life. If you keep your hypothyroidism well-controlled, it will not shorten your life span.

This is frightening. Frightening to experience the destructive effects of radiation. Frightening at the thought of lifetime medication. Frightening to see my body parts breaking down one by one. "Therefore we do not lose heart. Though outwardly we are wasting away, yet inwardly we are being renewed day by day" (2 Cor 4:16).

thanks for walking with me through this long & lonely journey,

tsk tsk