Does your mom see an Endocrinologist for her hypothyroid? Dr. Khoury on Northline in Southgate is awesome. A great website about thyroid cancer is www.thyca.org . Most cases of thyroid cancer are diagnosed in younger women, in their 20's or 30's. although there are different types of cancers of the thyroid, and some are more common over age 50, but that type is less commonly found at all. A few simple blood tests can reassure you :) Whoever prescribes her synthroid should be doing these tests yearly - TSH - thyroid stimulating hormone. Comes from the pituitary gland and tells the body that it needs to produce more thyroid hormone. Thyroglobulin - is the hormone that comes from the thyroid itself. Free T3 & Free T4 - one of them converts to the other, but I always forget which way, lol. When there's too much, it indicates that the synthroid doseage is too high, because the body is not using as much as is being provided.
I was diagnosed with thyroid cancer in 1989 (I was 24 yrs old) and had a total thyroidectomy. They never leave the thyroid in when it's cancerous. I had a total of 5 surgeries because it had spread to the lymph nodes. I've never heard of anyone complaining of shoulder/collar bone pain in relation to their thyroid/thyroid cancer. I actually had a node that was enlarged, kind of like when you're sick and your glands are big in your neck.
I do agree that your mom should have regular appointments with her doctor, to keep up on her thyroid levels and medication. And she should see an endocrinologist, not just her family doctor/internist.
In Michigan, we are in what's called the "thyroid belt" or "goiter belt." It's basically in the northern United States and it's from a lack of iodine in the ground soil, so also lower iodine levels in our food. When you ask around, alot of people you know have family members with thyroid problems.
Symptoms of hypothyroid are usually feeling super tired, just can't sleep enough, but also insomnia, dry skin, irritability, weight gain, feeling cold, constipation, brain fog.
Symptoms of hyperthyroid are a fast heartbeat, palpitations, losing weight without dieting, increased bowel movements, nervousness, feeling tired, feeling hot, hair loss...and if left untreated, you might notice their eyes sort of bulging (called exopthalmos).
More than likely your mom's shoulder pain is just age and the aches and pains that come with it :)
D.