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H Dralle

Publications and source records attributed to H Dralle.

At least 109 records · Page 6Linked to original sources
PubMed2000

[Quality assurance study in thyroid gland surgery. Initial comparative intermediate -term results for benign thyroid gland surgery]].

In 1998 the East German Association for Quality Securing of Surgery performed a study to evaluate the standard of performance of surgical treatment for benign goiter. In total, 46 hospitals participated and 6,029 operations could be analysed. The documentation was based on a detailed registration sheet and recorded items of preoperative complaints, diagnostic procedures, intraoperative findings with operative strategy, postoperative complications and definitive histology. All hospitals were divided into three groups regarding their number of surgical performances for benign goiter (< 50 operations, 50-150 operations, > 150 operations) to assess their training and expertise. Indications for surgical treatment were similar in all three groups with 78% for multinodular goiter and 19% for uninodular goiter. There was no statistical difference in distribution for M. Basedow, recurrent goiter or thyroid carcinoma. Hospitals with more than 150 operations per year for benign goiter performed statistical significant more extended procedures with routinely preparation of the laryngeal recurrent nerve and parathyroid glands. There was no statistical significant difference regarding postoperative complications. Because of the not finished check up (follow up 6 months postoperative), results for temporary nerve palsies (3.9%) and temporary hypoparathyroidism (6.3%) could only be stated.

Cross-Sectional Studies↗
PubMed1999

Primary structure, gene expression and chromosomal mapping of rodent homologs of the MEN1 tumor suppressor gene.

Mutations of the MEN1 tumor suppressor gene cause the multiple endocrine neoplasia type 1 (MEN1) syndrome in humans, and they are involved in a variety of sporadic human endocrine tumors. We here characterize the MEN1 gene homologs of the mouse and rat. cDNA was isolated from a mouse phage library, and two alternative MEN1 mRNA transcripts containing variant 5' untranslated regions were identified by RT-PCR in several mouse and rat tissues. When compared to the human molecule, mouse and rat MEN1 (611 and 610 amino acids, respectively) show an overall identity of 96.5% and 97.0% at the protein level, delimiting four conservational domains (A-D). Mouse and rat MEN1 mRNA, as studied by template-calibrated quantitative RT-PCR, is non-exclusively expressed in hematopoietic and endocrine cells, with similar expression patterns found in fetal and adult tissues. Fluorescent in situ hybridization maps the single murine MEN1 locus to chromosome 19, region B. No MEN1 gene mutations were identified in endocrine islet tumor cell lines RIN 5AH (rat) and NIT-1 (mouse) as compared to wild type cDNA. Our data define mouse and rat MEN1 as widely expressed and highly conserved homologs of the human MEN1 tumor suppressor gene whose role in biology and endocrine tumorigenesis is due for experimental study.

Animals↗
PubMed1999

Over-representation of a germline RET sequence variant in patients with sporadic medullary thyroid carcinoma and somatic RET codon 918 mutation.

The aetiology of sporadic medullary thyroid carcinoma is unknown. About 50% harbour a somatic mutation at codon 918 of RET (M918T). To investigate whether other RET sequence variants may be associated with or predispose to the development of sporadic medullary thyroid carcinoma, we analysed genomic DNA from the germline and corresponding tumour from 50 patients to identify RET sequence variants. In one patient, tumour DNA showed a novel somatic 12 bp in-frame deletion in exon 15. More interestingly, we found that the rare polymorphism at codon 836 (c.2439C > T; S836S) occurred at a significantly higher frequency than that in control individuals without sporadic medullary thyroid carcinoma (Fisher's exact test, P = 0.03). Further, among the nine evaluable cases with germline c.2439C/T, eight also had the somatic M918T mutation in MTC DNA which was more frequent than in patients with the more common c.2439C/C (89% vs 40%, respectively; Fisher's exact test, P = 0.01). These findings suggest that the rare sequence variant at codon 836 may somehow play a role in the genesis of sporadic medullary thyroid carcinoma.

Carcinoma, Medullary↗
PubMed1999

Minimally invasive surgery for recurrent neuroendocrine carcinoma of the supraglottic larynx.

Calcitonin-secreting neuroendocrine carcinomas of the supraglottic larynx are infrequent tumors, making it difficult to agree on treatment plans for recurrent tumors. Furthermore, this rare malignancy is often confused with the more common medullary thyroid carcinoma, resulting in inappropriate thyroidectomies. We present a case report of a calcitonin-secreting recurrent neuroendocrine carcinoma of the supraglottic larynx, in which surgery and pentagastrin stimulation were performed repeatedly at various stages of the disease. The recurrent laryngeal tumor was ultimately identified and, after construction of a protective tracheostomy, resected transorally en bloc with the underlying arytenoid cartilage. Postoperatively, the patient did well and stimulated calcitonin levels never exceeded double baseline values. Laryngoscopic removal of smaller laryngeal carcinomas is both technically feasible and safe, even when tumors are recurrent. In calcitonin-secreting malignancies, pentagastrin stimulation may facilitate the distinction between laryngeal and medullary thyroid carcinoma and thus help avoid unnecessary thyroidectomies.

Calcitonin↗
PubMed1999

C-cell cancer--prevention and treatment.

INTRODUCTION: C-cell cancer of the thyroid or medullary thyroid carcinoma (MTC) exists in a sporadic and a hereditary form, the latter of which is part of the multiple endocrine neoplasia type-2 (MEN-2) syndromes. DISCUSSION: MTC metastasises early to local (lymph nodes) and distant sites (liver, lung, bone). Therefore, early detection is mandatory to enable a chance of cure. In sporadic MTC, the sensitive tumour marker calcitonin enables detection of the disease at an early stage. In hereditary MTC, more than 95% of the patients have germline RET mutations. Thus, MEN-2 has become the paradigm for the practice of molecular medicine, and gene carriers can be identified before MTC even occurs. Surgery is the only chance of cure and recently developed surgical techniques provide the therapeutic prerequisite to achieve calcitonin normalisation in both sporadic and hereditary MTC.

Carcinoma, Medullary↗
PubMed1999

Expression of wild-type ret, ret/PTC and ret/PTC variants in papillary thyroid carcinoma in Germany.

INTRODUCTION: Papillary thyroid carcinoma (PTC) is the most common thyroid malignancy. Although the clinical course is usually rather benign, a subset of tumors is more aggressive. The ret/PTC oncogene was found only in PTC, with varying frequencies of up to 30%. Recently, two new variants of ret/PTC could be identified in post-Chernobyl PTCs, which raised the possibility that the prevalence of ret/PTC in non-radiation-induced PTCs might be higher than previously described. Normal thyroid cells do not express wild-type ret, but there is evidence that ret activation from any cause, including wild-type ret, occurs in more than a half of papillary tumors. METHODS: We used reverse transcription polymerase chain reaction and sequencing to examine wild-type ret and all five forms of ret/PTC known today in 99 PTCs from Hannover, Dusseldorf, Halle and Regensburg. Our method could also detect other variants within the known breakpoint regions. The presence of the ret tyrosine-kinase domain was examined by immunohistochemistry. RESULTS: Seven PTC1-positive tumors and one PTC3-positive tumor (8%), but none with the new variants or other variants of PTC1, 2 or 3 could be detected. Of 43 tumors examined, 20 showed expression of wild-type ret mRNA and staining of ret protein located predominantly to the cell membrane. CONCLUSION: Variants of ret/PTC do not substantially contribute to non-radiation-related ret/PTC-positive tumors, and the prevalence of ret/PTC in Germany is low in contrast to the high rate of wild-type ret expression. Thus, expression of wild-type ret should be examined for pathogenic, prognostic and possible therapeutic implications.

Carcinoma, Papillary↗
PubMed1999

Repeat mediastinal lymph-node dissection for palliation in advanced medullary thyroid carcinoma.

BACKGROUND: In medullary thyroid carcinoma (MTC), the effectiveness of repeat mediastinal lymph-node dissection for palliation of specific symptoms caused by discrete mediastinal lesions is unclear in non-bulky tumor disease. METHODS: Between November 1994 and August 1998, five symptomatic MTC patients with radiologic evidence of mediastinal tumor and elevated calcitonin levels were subjected to repeat mediastinal lymph-node dissection. RESULTS: At reoperation, an average of 7 of 25 (28%) removed cervical and 5 of 9 (56%) dissected mediastinal lymph-nodes were positive on histopathology. A substantial fraction of these were excised from anatomical regions inaccessible through a purely cervical or partial sternotomy approach. Clinical symptoms were effectively palliated in all five patients. Basal serum calcitonin levels fell only moderately, suggesting distant micrometastases. Mortality was nil. Morbidity encompassed two cases of hypoparathyroidism and a lymphatic fistula that closed spontaneously on total parenteral nutrition. One patient later required cervical reoperation deferred at secondary surgery. All five patients have since remained free of cervical and mediastinal tumor at a mean follow-up of 15 months. CONCLUSIONS: In mediastinal lymph-node metastases, repeat lymph-node dissection is warranted for palliation of discrete anatomic lesions inaccessible through a cervical approach.

Adult↗
PubMed1999

Minimally invasive video-assisted parathyroidectomy--selective approach to localized single gland adenoma.

BACKGROUND: The valid operative standard for primary hyperparathyroidism (pHPT) consists of cervicotomy and presentation of all parathyroid glands. This operative technique features the macroscopic identification of the responsible adenoma. It also has the advantage of detecting multiglandular disease. The increasing sensitivity of preoperative localization methods and the possibility of intra-operative measurement of parathyroid hormone prepared the way for minimally invasive procedures. METHODS: All patients with pHPT were examined by cervical sonography and sestamibi scintigraphy of the parathyroid glands. Patients eligible for the described procedure had to comply to the following inclusion criteria: biochemical evidence of pHPT, localization of one unequivocally enlarged parathyroid gland on two corresponding imaging results; no former surgery or radiation to the neck; no multinodular goiter; no suspected carcinoma of the thyroid; and no secondary or recurrent hyperparathyroidism. We used an operative technique first described by Miccoli in 1997. Before preparation and at 2, 10 and 15 min after exstirpation of the parathyroid adenoma, peripheral blood was drawn. The operation was terminated when a 50% decrease of preoperative PTH levels was reached. RESULTS: During a 12-month period (1 December 1997 to 30 November 1998), 13 patients with pHPT of a total of 59 patients (22%) with hyperparathyroidism (pHPT and sHPT) were operated on employing this minimally invasive procedure. In three patients, the operative technique had to be converted to the conventional procedure due to superior adenomas in two cases and a dorsoesophageal adenoma in one case. The procedure could thus be successfully completed in ten patients. The overall failure rate was zero in all patients with regard to the underlying disease. There was one temporary, recurrent laryngeal-nerve palsy. The mean overall length of the hospital stay was 3 days. CONCLUSION: The minimally invasive video-assisted parathyroidectomy for localized single-gland adenoma is a new and attractive surgical therapy option for primary hyperparathyroidism due to improved patient comfort, shortened length of hospital stay and favorable cosmetic results. This may lead to one-day surgery and, therefore, to a reduction of overall costs.

Adenoma↗
PubMed1999

[Surgery for hyperthyroidism].

The concept of therapy for hyperthyroidism combines endocrinology, nuclear medicine and surgery. For selection of the treatment of choice, pathophysiology as well as individual aspects are considered. Surgical therapy is mainly concerned with treatment of functional autonomy, Grave's disease and iodine-excess-related hyperthyroidism based on either autonomous or Grave's disease. For each of these three main groups of hyperthyroidism exist differentiated surgical concepts based on the underlying thyroid disease and its course: The various forms of functional autonomy, solitary autonomous nodules, multifocal autonomy or disseminated autonomy are dealt with selective enucleation-resection, functionally and morphologically oriented resection and extensive resection with little remaining thyroid tissue of about 5-6 ml, respectively. For Grave's disease extensive resections with thyroid-tissue remainders of about 2-4 ml or tatal thyroidectomy are established; the latter demonstrating in cases of concomittant endocrine ophthalmopathy the most convincing results. In cases of iodine-related hyperthyroidism the concept of early and radical surgical treatment, following stabilization of the patient in a reasonably short amount of time shows best results and is thus favored. In these cases, contrary to all other forms of hyperthyroidism, establishment of preoperative euthyroid metabolism is not mandatory.

Humans↗
PubMed1999

Diagnostic strategies and surgical procedures in persistent or recurrent primary hyperparathyroidism.

The incidence of persistent or recurrent primary hyperparathyroidism reported in the literature lies between 1 and 10%. The main causes are represented by atypical locations or incorrect diagnosis of primary parathyroid hyperplasia. Since primary parathyroidectomy by an experienced surgeon has a success rate of 95%, there is no need for extended imaging studies prior to initial bilateral exploration. After confirming diagnosis of persistent or recurrent hyperparathyroidism exact localization studies are necessary. The most important procedures are ultrasonography, magnetic resonance imaging, technetium Tc99m sestamibi scintigraphy with a combined sensitivity of approximately 90%. In case of negative imaging results selective venous catheterization before reoperation can be performed. Reoperation by an experienced surgeon will be successful in 95% of cases.

Diagnostic Imaging↗
PubMed1999

Regulation of CD97 protein in thyroid carcinoma.

CD97 is a dimeric glycoprotein belonging to the secretin receptor superfamily and is abundantly expressed in cells of hematopoietic origin. The aim of this study was to analyze the expression of the CD97 protein in thyroid carcinomas and the role of all-trans-retinoic acid (RA) in the regulation of CD97 protein in monolayer culture of the human follicular thyroid carcinoma cell line FTC-133. In normal thyroid tissue, no immunoreactivity of CD97 could be found, whereas in differentiated thyroid carcinomas, CD97 expression was either lacking or low. Undifferentiated anaplastic thyroid carcinomas revealed high CD97 expression. The expression of CD97 protein seems to be correlated to the postoperative histopathological classification staging. Approximately 50% of FTC-133 cells expressed the CD97 protein under basal culture conditions. No differences were found in the number of CD97-positive cells after TSH, forskolin, and insulin treatment compared to control values. Epidermal growth factor treatment led to an increase in CD97 immunostaining (up to 90%), whereas phorbol 12-myristate 13-acetate slightly decreased the immunoreactivity of CD97 (from 50% to 30%). Under basal conditions, RA treatment for 72 h led to a decrease in total cell number by 33% and in CD97-positive cells from 50% to 30%. TSH, forskolin, phorbol 12-myristate 13-acetate, and insulin showed no effect after 72-h pretreatment with RA, whereas epidermal growth factor treatment led to a slight increase in the number of the CD97-positive cells (from 30% to 40%) compared to the control value. These data suggest that CD97 expression may play an important role in the dedifferentiation of thyroid tumors, and RA might interfere with this process in thyroid carcinoma by suppressing the dedifferentiation marker CD97.

Adult↗
PubMed1999

Mutation analysis reveals novel sequence variants in NTRK1 in sporadic human medullary thyroid carcinoma.

Tyrosine kinase NTRK1 is expressed in neural and nonneuronal tissues. Like RET, NTRK1 is often activated by rearrangements that involve one of at least five other genes in papillary thyroid carcinoma (PTC). Because of similarities in involvement of the two tyrosine kinases RET (rearranged during transfection) and NTRK1 in the pathogenesis of PTC, the obvious parallels between RET and NTRK1 and between PTC and medullary thyroid carcinoma (MTC), NTRK1 seemed to be an excellent candidate gene to play a role in the genesis of MTC. Single-strand conformational polymorphism analysis of 16 exons of NTRK1, from 31 sporadic MTC, revealed variants in five exons (exons 4 and 14-17). Sequence analysis demonstrated one sequence variant each in exons 4, 14, 16, and 17, and four different variants in exon 15. Differential restriction enzyme digestion specific for each variant confirmed the sequencing results. All variants were also present in the corresponding germline DNA. Interestingly, the sequence variants at codon 604 (c1810C>T) and codon 613 (c1838G>T) ofexon 15 always occurred together and might represent linkage disequilibrium. The frequencies of the sequence variants in germline DNA from patients with sporadic MTC did not differ significantly from those in a race-matched control group. Although we did not find any somatic mutations of NTRK1 in sporadic MTC, the single-strand conformational polymorphism conditions reported here, together with the knowledge of the frequency of various sequence variants, may help in future mutation analyses of DNA from other neural and nonneural tissues.

Carcinoma, Medullary↗
PubMed1999

[Surgical treatment of Graves' disease].

In the surgical treatment of Graves' disease, there are several concepts established. The methods of bilateral subtotal resection, hemithyreoidectomy combined with contralateral subtotal resection, near-total resection and total thyreoidectomy all have there rightful placement in the surgical treatment of Graves' disease. The method of choice should be selected according to the activity of the disease. To avoid a recurrence of the disease, the more aggressive resections have proven to be more successful and there's evidence of preference of these techniques lately. Despite the more refined surgical techniques, the radical resections are still burdened with higher complication rates, specifically recurrent nerve palsy and hypoparathyroidism. Due to the excellent long lasting results of total thyreoidectomy, this concept appears to be the most convincing when technically well administered as it reliably cures the disease. The further development and regular use of technical aid such as surgical magnification lenses and neuromonitoring are expected to eventually help improve the more radical surgical concepts in the future. The prospect of combining surgical therapy with radioiodine-therapy may represent a chance to cure Graves' disease effectively and minimize complications from different sides.

Graves Disease↗
PubMed1998

Cytogenetic characterization of ten malignant fibrous histiocytomas.

We examined 10 malignant fibrous histiocytomas (MFHs) using metaphase preparations. Six tumors showed clonal structural and/or numerical chromosomal aberrations, and four tumors had normal karyotypes. For the most part, chromosomes 1, 3, 6, 9, 12, 16, 18, and 20 were involved in structural aberrations. The breakpoint regions most frequently were in 1p32, 3p25, and the centromeric region of chromosomes 1 and 16. There was a conspicuous loss in chromosome 18. We detected ring chromosomes in two tumors. One tumor showed a high percentage of near-haploid cells. Our results show many parallels to data which have already been published. MFHs include a broad spectrum of tumors of widely different histology and clinical course. So it is not surprising to find a cytogenetic diversity of chromosomal aberrations in this study.

Aged↗
PubMed1998

Determinative factors of biochemical cure after primary and reoperative surgery for sporadic medullary thyroid carcinoma.

Normalization of calcitonin levels after surgery has been regarded as the most powerful prognostic factor for medullary thyroid carcinoma (MTC). Although the prognosis of patients with persistent hypercalcitoninemia may be acceptable, the biochemical cure rate can be improved by new microdissection techniques. This raises certain questions: Can extension of locoregional lymphadenectomy (LA) further improve biochemical cure and survival after primary or reoperative MTC surgery? Which factors concerning TNM categories are associated with the possibility of postoperative normalization of calcitonin levels? This study included 64 patients with sporadic MTC operated on from 1986 to 1997. Altogether 27 patients underwent primary surgery, and 37 patients were reoperated, performing a microdissection of all four locoregional compartments (four-compartment lymphadenectomy, or 4CLA). For primary MTC the biochemical cure rate was 100% in node-negative patients and 33% in node-positive patients; the latter could be improved to 45% after 4CLA. In contrast to reoperative MTC, the rate of lymph node metastases (LNMs) with primary MTC correlated with the pT category (pT1 33%, pT2 53%, pT3 100%, pT4 100%) but not with age or sex. Again in contrast to reoperative MTC, mediastinal LNMs in primary MTC were present only in patients with a pT4 tumor. At reoperation, 4CLA was able to cure 22% of node-positive patients, 28% without proved distant metastases. No patient with extrathyroidal tumor involvement or distant metastases was biochemically cured after either primary or reoperative surgery. For all node-positive MTC patients, in addition to cervicocentral LA at least a bilateral cervicolateral LA is recommended. Transsternal mediastinal lymph node dissection is indicated in patients with LNMs in the cervicomediastinal transition, facilitating biochemical cure in up to 45% after the first operation and 22% after reoperative surgery of sporadic MTC.

Adult↗
PubMed1998

Prophylactic thyroidectomy in 75 children and adolescents with hereditary medullary thyroid carcinoma: German and Austrian experience.

When mutations of the RETproto-oncogene were found in 1993 to account for hereditary medullary thyroid carcinoma (MTC), surgeons obtained the opportunity to operate on patients prophylactically (i. e., at a clinically asymptomatic stage). Whether this approach is justified, and, if so, when and to which extent surgery should be performed remained to be clarified. A questionnaire was sent to all surgical departments in Germany and Austria. All of the patients who fulfilled the following criteria were enrolled: (1) preoperatively proved RET mutation; (2) age </= 20 years, (3) clinically asymptomatic thyroid C cell disease; and (4) TNM classification pT0-1/pNX/pN0-1/M0. Seventy-five patients were identified, and fifteen mutations were detected in six codons. Two adolescents had unilateral pheochromocytomas as part of the multiple endocrine neoplasia II (MEN-II) syndrome. No hyperparathyroidism was noted. All patients underwent total thyroidectomy, and 57 patients went on to have lymph node dissection. Parathyroid glands were removed in 34 patients and autografted in 11. Histopathology revealed MTC in 46 patients (61%, youngest 4 years); C cell hyperplasia (CCH) only was detected in the other 29 patients. Three patients had lymph node metastases (LNMs) the youngest being age 14 years. Calcitonin levels were not useful for differentiating between CCH and MTC, but in all patients with LNMs at least the stimulated calcitonin levels were assayed. After surgery, five patients (6.7%) sustained permanent hypoparathyroidism, and one patient (1.3%) had a permanent unilateral recurrent nerve palsy. All but three patients (96%) were biochemically cured. In conclusion, prophylactic total thyroidectomy can be performed safely in experienced centers. We recommend prophylactic total thyroidectomy at age 6. Cervicocentral lymph node dissection should be included when calcitonin levels are elevated or if patients are older than 10 years. Bilateral lymph node dissection should be performed if LNMs are suspected or when patients with elevated calcitonin are older than 15 years.

Adolescent↗