FOLLICULAR THYROID CANCER PRESENTING AS AN AUTOMOUS FUNCTIONING THYROID NODULE

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: SUN 459-496-Thyroid Neoplasia & Case Reports
Clinical
Sunday, June 16, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board SUN-480
Uzma Zohra Shafqat*1, David Bleich2 and Maya P Raghuwanshi3
1UMDNJ, Parsippany, NJ, 2UMDNJ-NJ Med School, Newark, NJ, 3UMDNJ-NJ Med Sch, Newark, NJ
INTRODUCTION: Differentiated or undifferentiated carcinoma in an autonomous functioning thyroid nodule is exceedingly rare.  Here, we report a case of unexpected discovery of follicular thyroid carcinoma in a toxic nodule.

 THE CASE: 52 yr old Hispanic male presented with weight loss, heat intolerance, insomnia and palpitations.  His labs showed suppressed TSH and high T4 and T3. On physical examination a thyroid nodule was felt as a firm mass 4x4 cm in lower left lobe of the thyroid.  Methimazole and Propranolol were initiated and this resolved his symptoms. Thyroid uptake and scan identified an area of increased uptake in the left lobe, with suppression of the right lobe.  He was treated with 25 mCi I-131 and then continued on propranolol and methimazole after failed thyroid nodule ablation. The patient discontinued medication on his own and developed recurrence of his symptoms requiring immediate treatment with beta-blocker, methimazole and steroids in the Emergency Room.  He required a second treatment with 31.31 mCi of RAI.  Multiple attempts to completely withdraw him from anti-thyroid medication failed.  He eventually developed compressive symptoms due to an enlarging thyroid mass.  A CT scan of the neck revealed heterogeneity of the left lobe of the thyroid gland, coarse calcification, narrowing of tracheal lumen, esophageal deviated towards the right, but no lymphadenopathy. The patient underwent a left lobectomy and was found to have moderately differentiated invasive follicular thyroid carcinoma with multiple nodules ranging from 0.6 to 4.0 cm. A completion thyroidectomy was performed one month later. The pathological findings in the right lobe depicted atrophy and interstitial fibrosis suggesting suppression.  Post-operative thyroglobulin was 189.0 ng/ml (0.5-55.0) and anti-thyroglobulin antibodies were undetectable.  Abnormal I-131 uptake on a post-therapy scan was noted in the neck, left upper chest (clavicle), mid chest region (sternum), and diffusely in the liver.

DISCUSSION: Rare case reports can be found in the literature indicating thyroid malignancy in autonomous functioning thyroid nodule might be due to TSH receptor mutation and RAS gene mutation.  Our patient demonstrated follicular thyroid cancer in a toxic thyroid nodule.

Nothing to Disclose: UZS, DB, MPR

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