PDFQuestion
An 18 year old girl with diffuse miliary metastases of papillary thyroid cancer in lungs has had 200mc of I131 and we plan repeat doses every 6 months until no more uptake in lungs. This first dose was given after withdrawal of thyroid hormone. Would future doses after Thyrogen be as effective and less damaging to other tissues?
DW Ingram
St Clares Mercy Hospital
St Johns Newfoundland Canada A1C5B8
Response
One study reports lower whole body radiation using rhTSH in comparison to hormone withdrawal, but I do not believe the issue is settled as yet. Either approach should provide adequate stimulation of any thyroid tumor tissue. My personal preference is the "half-dose" method, outlined in www.thyroidmanager.org, which raises TSH effectively without inducing symptoms from hypothyroidism.
L De Groot, MD