FP14-4 A Thyroid Nodule with a Twist

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: FP14-Thyroid Cancer: Insights into Diagnosis & Treatment
Clinical
Saturday, June 15, 2013: 11:00 AM-11:30 AM
Presentation Start Time: 11:15 AM
Room 103 (Moscone Center)

Poster Board SAT-419
Amit Bhargava*1, Sameera Tallapureddy1, Sarah Varghese2 and Beatriz Tendler1
1University of Connecticut, Farmington, CT, 2University of Connecticut, Hartford, CT
Background: Rheumatoid nodules occur in 30% of patients with active rheumatoid arthritis (RA), and commonly involve sites like the extensor surface of the forearm. The authors present a unique case of the development of rheumatoid nodules in the thyroid bed of a patient, post thyroidectomy.

Clinical Case: A 46-year-old Caucasian lady, with active RA and Hashimoto’s thyroiditis, on hydroxychloroquine, prednisone and levothyroxine, presented with a goiter. She complained of dysphagia and a sensation of airway compression. The thyroid was enlarged. On ultrasound, the right lobe measured 7.9x3.4x3.3cm, the left lobe 8.3x3.3x3.1cm, and isthmus 2.1cm. TSH was 4.22 uU/ml (0.34-5.60). Due to a concern of worsening tracheal compression and growth of a nodule on levothyroxine, a total thyroidectomy was done (thyroid gland- 79g). Repeat ultrasound showed no remaining tissue. Pathology revealed several small neoplasms ranging from a well-encapsulated adenoma to highly atypical follicular and papillary Hurthle cell lesions, in the setting of Hashimoto’s thyroiditis. Due to this, low dose radioactive iodine (RAI) 33.4 mCi was given. 4 months later, the patient complained of neck fullness. A large solid nodule of mixed echogenicity (5.6x3.3x2.3cm) was seen in the right level VI of the neck, and solid tissue of mixed echogenicity (2.9x2.3x1.7cm) on the left. Repeat surgery yielded a 11g aggregate of soft, tan irregular tissue from the right, and 1g from the left.  Pathology from the right showed Hashimoto's thyroiditis. The left tissue specimen had areas of granuloma formation with fibrinoid necrosis and palisading histiocytes, consistent with the histology of a rheumatoid nodule. No malignant foci were seen. No further RAI was given and the patient remains disease free 4 years later.

Conclusion:  Rheumatoid nodules have not been reported in the thyroid bed. Their pathogenesis is not clear. Post-operative release of TNF- α and local vascular damage may have triggered nodule formation in this case. Rheumatoid nodules must be kept in the differential diagnosis of an enlarging thyroid, in the setting of active RA. This is especially relevant if there is a triggering factor such as small vessel trauma. Fine needle aspiration biopsy may show granuloma formation and be the most cost-effective initial step. Early identification of these nodules will help decrease morbidity from unnecessary interventions and result in treatment that is both timely and appropriate.

Nothing to Disclose: AB, ST, SV, BT

*Please take note of The Endocrine Society's News Embargo Policy at http://www.endo-society.org/endo2013/media.cfm