Brief Answer:
Its Autoimmune Thyroid disease(may be Hashimoto's thyroiditis)

Detailed Answer:
Dear XXXX!
Welcome to HealthCare Magic. I am Dr. Hanif. I apologize on part of HCM team for answering late, but I started at once I saw your query.
I have gone through your case and want to assure that you don't panic. People with autoimmune diseases live longer now a days with better treatment options. We can't completely cure, but can make life so easier as near to normal. Your T3,T4,TSH are normal. It means your thyroid is working normal. You just need follow up to see if autoimmune disease destroys your thyroid due to inflammation, you may not get hypothyroid. Right now you don't need Levothyroxine medicine, but may be needed in future if you test low thyroid hormones at follow up.
Every lab has different reference range. Less than 10 IU/ml is considered by Mayo Clinic. Some have 0-20 normal range. And you didn't mention the units with TPO ABS. Its mostly IU/ml. But the levels you gave are really high and suggests autoimmune disease without any doubt.
For such patients (who have high antibodies and thyroid hormones) I usually prescribe Levothyroxine (Levoxyl) then. It helps a lot of patients and they start feeling less fatigued soon after starting it. It reverses weight gain too, and lowers cholesterol levels elevated by the disease. Levoxyl is life long treatment usually. Follow up after 6-12 months are needed because your physician needs to adjust dosage according to TSH levels you have. Overdosage may cause heart rhythm disorder (arrhythmia).
You were asking about follow ups so I gave details just for you to calm down.
Talk to your physician if you take diet high in Soy-products and high fiber, because it causes Levothyroxine absorb slowly & in low amounts. So take Levothyroxine at least 3 hours before/after any other medicines and interfering products like soy, Iron supplements(or multivitamins),calcium aupplements. I have seen you said you are taking no medicine. So I am not worried about other drug interactions.
If you have some questions/doubts regarding medications you ever take, please ask a direct Question and I will never let you wait again for longer time.
And regarding any special diet?
Yes you need to take low fat diet and low carbohydrates. If you feel fatigued don't take energy drinks or junk food. Its not because of low sugar level in blood. Rather its due to autoimmune destructive process making thyroid fail due to inflammation.
Hope it helps. You may ask a direct Question for follow up and clear any doubts. I will be more than happy to answer.
Regards!

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Brief Answer:
Please don't worry. Let me explain it to you.

Detailed Answer:
Dear XXXX!
First of all, thyroid peroxidase antibodies being moderate never means Cancer. Its a wrong information you have read somewhere. Please don't bother. Secondly this number means JUST NOTHING (HAS ZERO IMPORTANCE) when you have thyroid profile normal. If your thyroid hormones were abnormal, then you needed to take medicines.
What I have to observe is the TSH, T4, T3 levels for you and if they are in normal limits, nothing needed to do as you can't kill the autoimmune disease which is causing inflammation of thyroid gland and thyroid gland in response to the inflammatory process is secreting this much thyroid peroxidase antibodies(TPO ABs). So raised TPO ABs over longer time shows that your thyroid is inflamed and is vulnerable to start working not enough to run the bodily functions properly. How we will know that this has happened? Thats why 6monthly follow up visits were recommended by me. What will a physician do for that? He will prescribe Levothyroxine to make you back normal(euthyroid) so that your T4, and T3 levels are replenished by medicines.
Right now you need no medicines, but in future you may/or/may not need it.
Please relax and stick to the medical advice of your treating physician, as you don't need a second opinion.

Regards!
Dr. Hnaif

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