40yr female had thyroid cancer 2017 had thyroidectomy.last consultant review jan 2020 normal blood result.recent blood test thyroglobulin ab 90.02 iu/ml range 0-4.11. free t4 1.01 ng/dl range 0.70-1.48 tsh 2.38 range 0.35-4.94 sign of cancer return?

I assume you had total thyroidectomy and you are on thyroid hormone replacement? Anti-Tg antibodies are detectable in as many as 10 percent of the general population and 20 percent of thyroid cancer patients. Thyroglobulin (Tg) values obtained in the presence of anti-Tg antibodies may not be clinically reliable for follow-up after total thyroidectomy for thyroid cancer.