Case of the Month ; May 2010; Contributed by Dr Anish Bhattacharya, PGI , Chandigarh
76/F Papillary Ca Thyroid diagnosed Mar 2009
Total thyroidectomy on 2/4/09
I-131 WBI scan on 16/5/2009 shows residual functioning tissue in the thyroid bed
Received 30 mci of I 131 on 18/5/09 at a different institute (Post-therapy scan NA)
Tg 22/5/09: 189ng/ml
I 131 scan 3/12/09: no Iodine-avid lesion
Tg 10/12/09: 186 ng/ml
FDG PET-CT done on 14/12/09 shows two foci of FDG uptake, one in the thyroid bed, and another in a left cervical lymph node
The case illustrates the utility and need for an FDG PET scan in case of a negative I-131 scan with raised Tg, to detect any non-Iodine –avid residual tissue or mets.
However, the treatment options are limited:
Redifferentiation therapy followed by Radioiodine therapy, if successful.
Repeat surgery, if feasible.
External radiotherapy, in suitable situations.
Chemotherapy, if all else fails.
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