E.F. RITTINGHAUS, M. BURDELSKI, H. DRALLE and H. JÜPPNER
H. DRALLE, S. SCHRÖDER, K. F. GRATZ, K. NEUMANN and R. D. HESCH
D Fuhrer, M Eszlinger, S Karger, K Krause, C Engelhardt, D Hasenclever, H Dralle and R Paschke
Objective: We evaluated three markers (insulin-like growth factor II (IGF-II), cyclooxygenase-2 (COX-2) and ets-1) of thyroid growth stimulation and cell transformation together with a thyroid-specific marker (thyroglobulin (Tg)) for their potential to differentiate benign and malignant follicular thyroid neoplasia (FN).
Design and methods: mRNA expression levels were determined by real-time PCR in 100 snap-frozen thyroid samples: 36 benign thyroid nodules with different histology and function (19 cold (CTN) and 17 toxic thyroid nodules (TTN)), 36 corresponding normal thyroid tissues of the same patients, eight Graves’ disease (GD) thyroids, 10 follicular thyroid carcinomas (FTC) and 10 papillary thyroid carcinomas (PTC).
Results: Mean IGF-II and COX-2 levels were not significantly altered between benign and malignant thyroid nodules (IGF-II) or nodular (FTC, TTN, CTN) and normal thyroid tissues (COX-2). In contrast, eight- to tenfold upregulation of ets-1 was observed in PTC and three- to fourfold upregulation of ets-1 was observed in FTC (and GD) compared with benign thyroid nodules and normal thyroid tissues. In addition, thyroglobulin mRNA expression was markedly downregulated (50- to 100-fold) in FTC, PTC and GD samples compared with benign nodular and normal thyroid tissues. Hence an ets-1/Tg ratio >20 distinguished differentiated thyroid cancer from benign nodular or normal thyroid tissue. We then studied ets1- and Tg mRNA expression levels in fine needle aspiration cytology (FNAC) samples. However, in a consecutive series of 40 FNAC samples only equivocal results were obtained on 38 benign and two malignant (FTC) thyroid tumour samples.
Conclusions: Upregulation of ets-1 and downregulation of Tg mRNA expression occur in differentiated thyroid cancer and may facilitate pre-operative identification of thyroid malignancy depending on further evaluation of these potentially promising markers in a larger series of benign and malignant thyroid tumours and their FNAC samples.
K Frank-Raue, H Buhr, H Dralle, E Klar, N Senninger, T Weber, S Rondot, W Höppner and F Raue
Objective: In children with RET proto-oncogene mutation, curative treatment of medullary thyroid carcinoma (MTC) is possible by prophylactic thyroidectomy. Recommendations on the timing and extent of thyroidectomy are based upon a model that utilises genotype–phenotype correlations to stratify mutations into three risk groups.
Design: We evaluated the long-term outcome (mean follow-up 6.4 years, 15 patients more than 10 years, 26 patients more than 5 years) of operated gene carriers stratified into two risk groups (levels 1 and 2) based on the biological aggressiveness of MTC.
Results: In 46 RET gene carriers, prophylactic thyroidectomy was carried out between the ages of 4 and 21 years. Level 1 mutations were harboured by 11 patients (codons 790, 791, 804 and 891). Histology was completely normal in two patients; in seven patients C-cell hyperplasia (CCH) and in two patients T1 tumours were diagnosed. All patients with level 1 mutations were cured. Level 2 mutations were harboured by 35 patients (codons 618, 620, 630 and 634). Histology of these patients showed CCH in 11 patients, T1 tumours in 21, T2 tumour in 1, T3 tumour in 1 and Tx in 1 patient. Histology showed no lymph node involvement. Five patients with level 2 mutations failed to be cured; in two patients, persistence of MTC was diagnosed directly after thyroidectomy and in three during follow-up. In two patients carrying a 634 mutation, other endocrinopathies (hyperparathyroidism and bilateral pheochromocytoma) manifested during follow-up.
Conclusions: If prophylactic thyroidectomy is done at early ages, cure rate is high. Timing and extent of prophylactic thyroidectomy can be modified by individual RET mutation.
M Blaker, A de Weerth, M Tometten, M Schulz, W Hoppner, D Arlt, C Hoang-Vu, H Dralle, H Terpe, L Jonas and T von Schrenck
OBJECTIVE: The cholecystokinin(2)-receptor (CCK(2)R) promotes secretion and cell growth induced by its ligands cholecystokinin (CCK) and gastrin. The receptor has recently been shown to be expressed in human medullary thyroid carcinomas (MTCs). The objective of this study was to analyze CCK(2)R expression in MTC samples of different tumor stages as well as in non-malignant thyroid tissues. DESIGN AND METHODS: Using RT-PCR we investigated 19 MTC samples and TT-cells (a human MTC cell line), as well as samples of normal thyroid. In addition, we performed immunohistochemistry using calcitonin- and CCK(2)R-specific antibodies on MTCs and samples of C-cell hyperplasia. RESULTS: We demonstrate for the first time that CCK(2)R is expressed not only in MTCs but in all samples of normal thyroid tissue. Using immunohistochemistry the receptor could be localized on calcitonin-secreting C-cells. The highest incidence of CCK(2)R expression in MTCs was observed in early-tumor stages, whereas CCK(2)R could not be detected in advanced or metastasized tumors. CONCLUSIONS: The expression of CCK(2)R in C-cells suggests a physiological function for gastrin and/or CCK in the regulation of calcitonin release, presumably related to bone and calcium metabolism. Moreover, these ligands might act as growth factors in MTCs. Efforts in the development of CCK(2)R scintigraphy for the detection of MTC lesions might have to consider a lower incidence of the receptor in advanced tumor stages.