Question
I would like to ask your expert opinion on a 64 years old lady with Hurthle cell thyroid carcinoma. She also has type 2 DM. She had initially sub-total excision of the thyroid gland without previous fine-needle aspiration biopsy in her local hospital. Histopatology had revealed Hurthle cell thyroid carcinoma (diameter of tumor: 4 cm with capsule and vascular invasion). Then, completion thyroidectomy has been performed shortly after initial thyroidectomy in another teaching hospital. But, surgeon had not been able to successively remove all thyroid tissue and tumor because of locally aggressive disease. She received RAI therapy 6-months after completion thyroidectomy (125 mCi of Iodine-131 orally) by using recombinant TSH since the TSH on LT-4 off was sub-therapeutic (10 mIU/L). Pre-RAI thyroglobulin was > 1500 ng/ml and thyroglobulin antibody was <40 IU/L. Whole body survey, 7 days after the RAI dose showed a focal moderately intense abnormal radioiodine accumulation in the thyroid area in the midline. Thyroglobulin level did not declined after RAI yherapy, even increased. Then patient underwent FDG-PET CT scan. Scan revealed intense uptake of FDG in the left paratracheal region, right upper, middle and lower pulmonary segments (solitary metastasis documented by conventional CT without contrast). I thought that metastatic lesions were not amenable to surgery or external beam radiotherapy, patient underwent second course of RAI therapy (200 mCi) 6-months after previous one. Post-treatment RAI scan showed no uptake in the neck and mediastinum, but uptake in the right middle and lower segment of lung. At this time, I switched her oral anti-diabetic treatment from sulfonylurea to rosiglitazone 8 mg/day since recent reports indicated enhanced radioiodine uptake in patients with poorly differentiated papillary thyroid cancer after treatment with rosiglitazone. After second course of RAI therapy thyroglobulin level did not show significant fall. During this time, she developed 1.5 cm swelling in thyroidectomy incision area, which was sonographically compatible with metastasis in subcutaneous area. Repeat FDG-PET CT scan revealed intense uptake in neck subcutaneous area, left thyroid area, right paratracheal area, right hilar area, and multipl metastatic nodules in the right pulmonary field (new metastatic areas are present). How do I best manage this patient? Is there an indication for higher dose of RAI therapy (possibly with lithium) ? or is it time for hands-up?
Alptekin Gursoy, MD
Baskent University Faculty of Medicine
ANKARA, Turkey
Response
This is indeed a difficult tumor to treat. We generally attempt to control the neck disease with surgery and external beam therapy (which is what I would primarily consider for this patient).
With regards to radioiodine, I would consider a dosimetry approach after the neck surgery and prior to EBRT to see if a large dose of radioiodine (using lithium) can provide benefit for the distant metastases ' based on the previous therapy, I am concerned that radioiodine may not benefit this patient, but the dosimetry/lithium approach is not unreasonable.
Standard chemotherapy is unfortunately not very effective, but we have had some anecdotal responses to adriamycin + taxol in some patients who have progressive disease that does not respond to radioiodine therapy.
We also consider entering these patients into clinical trials or use some of the newer agents (off-label) that are approved for use in other cancers in the US (sorafenib, sunitinib, gefitinib). I am not sure what is available in Turkey.
The primary goal is to control the progressive locoregional disease (surgery, EBRT) and either systemically treat (RAI) the metastatic disease, or follow if stable.
Bryan Haugen, MD