• Korean Journal of Head & Neck Oncology
• /
• v.28 no.2
• /
• pp.132-134
• /
• 2012

Ectopic thyroid is an uncommon embryologic aberration characterized by the presence of thyroid tissue in a site other than its usual pre-tracheal location. Dual ectopic thyroid is extremely rare, only few cases have been reported in the literature. Physical examination, laboratory test and radiologic examinations are usually performed for the diagnosis and therapeutic plan of dual ectopic thyroid. We report a 36-year old female with dual ectopic thyroid in lingual and hyoid regions but without thyroid tissue in its normal area. The diagnosis was made through pathologic examination after surgical resection.

• Nuclear Medicine and Molecular Imaging
• /
• v.42 no.6
• /
• pp.485-487
• /
• 2008

Ectopic thyroid is not common disease and double ectopic thyroid is rare. Until January of 2008, dual ectopic thyroid has been reported only 23 cases in international literatures. Tc-99m sodium pertechnetate scan is playing an important role in the diagnosis of ectopic thyroid. In most of the cases, dual lingual thyroid tissues could be detected as two radiotracer uptake foci. We report a case of dual lingual thyroid mimicking mono-lingual thyroid in the anterior view of thyroid scan. Lateral view helped in this case to detect the dual lingual thyroid. With lateral view, the anatomical position and relationship could be examined in more detail.

• Korean Journal of Head & Neck Oncology
• /
• v.30 no.2
• /
• pp.53-61
• /
• 2014

Background and Objectives : Anaplastic thyroid carcinoma(ATC) is a rare but highly aggressive thyroid malignancy that is associated with an extremely poor survival despite the best multidisciplinary care. BRAF(V600E) mutation is detected in about a quarter of ATC, but unlike its high treatment response to selective BRAF inhibitor (PLX4032) in metastatic melanoma, the treatment response of ATC is reported to be low. The purpose of this study is to investigate the innate resistance mechanism responsible for this low treatment response to BRAF inhibitor and its effect on epithelial-mesenchymal transition(EMT). Materials and Methods : Two ATP cell lines, 8505C and FRO were selected and treated with PLX4032 and its drug sensitivity and effects on cell migration and EMT were examined and compared. Further investigation on the changes in signals responsible for the different treatment response to PLX4032 was carried out and the same experiment was performed on both orthotopic and ectopic xenograft mouse models. Results : FRO cell line was more sensitive to PLX4032 treatment compared to 8505C cell line. The resistance to BRAF inhibition in 8505C was due to increased expression of EGFR. Effective inhibition of both EGFR and p-AKT was achieved after dual treatment with BRAF inhibitor(PLX4032) and EGFR inhibitor(Erlotinib). Similar results were confirmed on in vivo study. Conclusion : EGFR-mediated reactivation of the PI3K/AKT pathway and MAPK pathway contributes to the relative insensitivity of BRAF(V600E) mutant ATC cells to PLX4032. Dual inhibition of BRAF and EGFR leads to sustained treatment response including cell invasiveness.