Mixed Medullary-Follicular Thyroid Cancer Treated with surgery and Radioiodine ablation

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: SAT 414-428-Thyroid Neoplasia & Case Reports
Clinical
Saturday, June 15, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board SAT-423
Alaaeldin Bashier*1, Fatheya Fardallah Alawadi2, Manal Abdulrahim1, Fouzia Rashid3 and Shaheenah Dawood3
1Dubai Hospital, Dubai, United Arab Emirates, 2Dubai Hospital, Ash Shariqah, United Arab Emirates, 3Dubai Hospital, United Arab Emirates
Mixed Medullary-Follicular Thyroid Cancer Treated with Surgery and Radioiodine ablation 

Background: Differentiated thyroid cancer is the commonest cancer affecting thyroid gland. Medullary thyroid carcinoma (MTC) constitutes 2-8% of all thyroid cancers. Simultaneous occurrence of mixed medullary and follicular thyroid carcinoma (mixed MTC-FTC) is a rare finding that poses challenges in diagnosis, treatment, follow up and future prediction of prognosis.

Clinical case: A 28 -year-old Emirati lady who presented with a neck swelling that increased in size over 2 months period. She was clinically and biochemically euthyroid. 99m Tc04 Thyroid scan showed a cold nodule in the right lobe of thyroid. Ultrasound thyroid confirmed the presence of hypoechoic well defined lesion. Fine needle aspiration biopsy (FNAB) revealed a medullary thyroid cancer. Following total thyroidectomy and lymph node dissection the histopathology showed a solitary tumour with mixed features, predominantly medullary with areas of follicular architecture, confirmed by immunohistochemical staining as mixed MTC-FTC. Work up for MEN II and RET-proto-oncogen was negative. 99m Tc (04) Thyroid scan postoperatively showed an increased uptake in the remnant thyroid tissue. She was treated with adjuvant radioactive iodine therapy. Her initial calcitonin level post operatively was 13.4pg/ml (NR < 5.0), CEA 36ng/ml (NR <3.8), and thyroglobulin was 0.7ng/ml (NR <1). On follow up visits, the thyroglobulin as well as calcitonin and CEA levels were suppressed. Follow up 99m Tc 04 thyroid scan and I131 scan were normal.

Conclusion: This case presents a challenge in management. We treated her surgically as well as radioactive iodine. Follow up with calcitonin and thyroglobulin did not show any evidence of recurrence. We recommend including mixed tumors in thyroid cancer management guidelines. 

Abbreviations:

MTC: Medullary Thyroid Cancer

FTC: Follicular Thyroid Cancer

RAI: Radioactive Iodine

TG: Thyroglobulin

ATG: Anti-thyroglobulin Antibodies.

CT: Calcitonin

FMTC: Familial medullary thyroid cancer

MEN: Multiple Endocrine Neoplasias

Nothing to Disclose: AB, FFA, MA, FR, SD

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