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B Niederle

Publications and source records attributed to B Niederle.

At least 37 records · Page 2Linked to original sources
PubMed2001

Treatment of gastric neuroendocrine tumors: the necessity of a type-adapted treatment.

BACKGROUND: Gastric neuroendocrine (or gastric carcinoid) tumors have recently been classified into 3 types that differ in biological behavior and prognosis. Although the necessity of type-adapted treatment is widely accepted, it seems inconsistently used in daily practice. HYPOTHESIS: Diagnostic differentiation into various biological types is necessary for an adequate treatment of gastric neuroendocrine tumors. DESIGN: Retrospective study. SETTING: University hospital department of surgery. PATIENTS: Twenty-seven patients with a histologically verified gastric neuroendocrine tumor. MAIN OUTCOME MEASURES: A univariate analysis of survival rates with respect to tumor type, tumor biological parameters, and treatment performed was accomplished by applying the Kaplan-Meier estimation method. The log-rank test was used to evaluate the level of significance. RESULTS: The 16 type 1 (59%) and 11 type 3 (41%) gastric neuroendocrine tumors differ in tumor size, histopathologic characteristics, and biological behavior. Nine (56%) of 16 type 1 gastric neuroendocrine tumors were treated by local excision, 8 of these (89%) had persistent atrophic gastropathy during the follow-up period. Five-year cumulative survival of patients with type 1 gastric neuroendocrine tumor was 100% without any progression into malignant phenotype. In contrast, 4 (44%) of 9 locally advanced type 3 gastric neuroendocrine tumors were treated radically by extended resection with a 5-year cumulative survival of 75%. CONCLUSIONS: Differentiation into 3 biologically distinct tumor types for gastric neuroendocrine tumors is important with respect to therapeutic strategy and prognostic consideration. Correct diagnosis is attainable by using endoscopy, histopathologic characteristics, and laboratory chemical analysis and should precede any treatment. Extended radical surgery of high-risk type 3 tumors is indicated when definitive healing is achievable, whereas type 1 tumors are best treated by endoscopic removal and long-term follow-up.

Carcinoid Tumor↗
PubMed2001

Minimally invasive open parathyroidectomy in an endemic goiter area: a prospective study.

HYPOTHESIS: Single-gland disease identified by preoperative localization studies in combination with rapid intraoperative parathyroid hormone monitoring seems to allow a limited exploration of the neck in sporadic primary hyperparathyroidism. Minimally invasive open parathyroidectomy by lateral approach (oMIP) in sporadic primary hyperparathyroidism seems feasible in an endemic goiter region. DESIGN: One hundred consecutive patients with sporadic primary hyperparathyroidism underwent preoperative double-phase technetium Tc 99m sestamibi scanning with single-photon emission computed tomography and high-resolution ultrasonography with color Doppler imaging of the cervical region. All patients were operated on with the use of quick parathyroid hormone assay to confirm the surgical success "on-line." Patients with localized single-gland disease, irrespective of additional ipsilateral thyroid disease requiring surgery, were selected for oMIP. Success of the preoperative localization studies, postoperative (at least 6 months) serum calcium levels, and operating time were analyzed. SETTING: University hospital, section of endocrine surgery. RESULTS: Of 100 patients, 83 (83%) were considered suitable for oMIP. In 69 patients, oMIP was finished successfully. Nine of these had had previous neck surgery, and another 24 underwent additional ipsilateral thyroid resection. Permanent normocalcemia was achieved in 67 (97.1%) of 69 patients and 98 (98%) of 100 patients. CONCLUSION: The oMIP in combination with quick parathyroid hormone assay may become the treatment of choice for sporadic primary hyperparathyroidism in an endemic goiter region in centers with high experience in thyroid and parathyroid surgery. It allows treatment of concomitant ipsilateral thyroid disease and is feasible in reoperations.

Adolescent↗
PubMed2001

Sporadic versus familial medullary thyroid microcarcinoma: a histopathologic study of 50 consecutive patients.

By means of calcitonin screening programs, sporadic and hereditary medullary thyroid carcinoma (MTC) can be detected at an early stage. We investigated the histopathologic findings of 16 familial (mean age 32 +/- 21 years, female/male ratio 1.6:1) and 34 sporadic (mean age 58 +/- 15 years; female/male ratio 2.4:1) MTCs with stage T1 comparatively. Patients with hereditary tumors were younger. Hereditary tumors were more often found multifocal (13 of 16 vs 3 of 34; p < 0.001), bilateral (11 of 16 vs 3 of 34; p < 0.001), displaying desmoplastic stroma (14 of 16 vs 19 of 34; p = 0.02), and accompanied by C cell hyperplasia (16 of 16 vs 24 of 34; p = 0.01), but all of these factors were present in some sporadic patients. Only tumors with desmoplastic stroma showed lymph node metastasis, which was observed in eight of the 50 patients. After surgery all patients showed permanent normalization of calcitonin levels. We conclude that 1) morphologic parameters considered to indicate familial MTC risk are of no value in the individual patient, 2) many sporadic MTCs develop on the background of CCH, 3) tumors with desmoplastic stroma are more likely to develop lymph node metastasis, and 4) early detection of MTC permits curative surgery in the majority of patients.

Adolescent↗
PubMed2001

FDG positron emission tomographic, radioiodine, and MIBI imaging in a patient with poorly differentiated insular thyroid carcinoma.

Poorly differentiated insular thyroid carcinoma is now classified as a separate entity among other tumors of the thyroid gland. Its histologic pattern and its clinical course are regarded as intermediate between well differentiated and anaplastic thyroid cancer. Insular carcinoma accumulates I-131, but no data exist regarding its fluorodeoxyglucose (FDG) positron emission tomographic (PET) uptake. The authors report F-18 FDG PET, Tc-99m MIBI, and radioiodine imaging features in a 63-year-old patient with metastatic insular thyroid carcinoma. After total thyroidectomy (for poorly differentiated insular carcinoma pT3a), the patient was referred for radioiodine ablation. No signs of recurrence were present until 16 months later, when thyroglobulin levels increased. An I-131 scan showed a single lesion in the right lung, and further radioiodine treatment was administered (cumulative dose [530 mCi], 19,610 MBq I-131). Three years after the initial diagnosis, FDG-PET and Tc-99m MIBI scans were performed within 5 days during thyroxine treatment. After that, thyroxine substitution was withdrawn; 6 weeks later, an I-131 whole-body scan was performed. Both radioiodine and MIBI images showed increased tracer uptake in the known lung lesion. However, FDG PET showed a normal tracer distribution. Magnetic resonance and computed tomographic imaging confirmed a 12-mm lesion in the right upper lobe. These findings support the concept of the "flip-flop phenomenon" in insular thyroid carcinoma, an alternating pattern of metastases with either I-131 or FDG-uptake. Despite poorly differentiated histologic findings, glucose metabolism was not increased in this patient with an insular tumor.

Carcinoma↗
PubMed2001

Quantification of unconjugated metanephrines in human plasma without interference by acetaminophen.

BACKGROUND: Pheochromocytoma is a rare cause of hypertension resulting from increased catecholamine secretion. We aimed to develop a method to measure unconjugated plasma normetanephrine (NMN) and metanephrine (MN) without interference from acetaminophen, a widely prescribed drug for headaches. METHODS: Plasma samples were obtained from 48 subjects (23 males, 25 females; mean age, 49 +/- 14 years; hypertension, n = 37) under resting conditions. Following extraction on solid-phase cation-exchange columns, unconjugated metanephrines were analyzed by HPLC with electrochemical detection and with 4-hydroxy-3-methoxybenzylamine as an internal standard. Catecholamines were measured by HPLC. RESULTS: The assays were linear up to 2000 pg for NMN and for MN. Intraassay imprecisions (CVs) were 4.7% for NMN and 7.0% for MN, and the interassay CV was 12% for both NMN and MN. The limit of detection was 11 fmol for NMN and 17 fmol for MN. Ingestion of acetaminophen or its addition to plasma did not interfere with the MN peaks. Plasma NMN and MN were positively correlated (r = 0.52 and 0.49, respectively; P <0.01 for both) with the respective catecholamines. Plasma NMN (r = 0.27; P = 0.02) but not MN positively correlated with age, whereas only plasma catecholamines (and not metanephrines) were positively correlated (P <0.05) with diastolic blood pressure. CONCLUSIONS: This sensitive MN assay is not affected by simultaneous acetaminophen medication, and reveals a correlation of metanephrines with plasma and urinary catecholamines and age but not with blood pressure.

Acetaminophen↗
PubMed2000

Diagnostic efficacy of unconjugated plasma metanephrines for the detection of pheochromocytoma.

BACKGROUND: Recently, measurement of plasma metanephrines was suggested to improve the detection of pheochromocytoma compared with the other common biochemical tests. OBJECTIVE: To examine the diagnostic precision of measurements of plasma metanephrines, plasma catecholamines, and urinary catecholamines and to assess their variability. METHODS: Plasma metanephrine as well as plasma and urinary catecholamine concentrations were measured by high-performance liquid chromatography with electrochemical detection. Before surgery, responses of plasma metanephrines and catecholamines to change of posture were determined. Intraoperatively, metanephrines and catecholamines were measured before skin incision, during maximal mechanical tumor manipulation, and repetitively after the tumor was separated from the circulation. Patients were reexamined 1 and 3 months after surgery. Patients with pheochromocytoma (n = 17) and with histologically proved other adrenal tumors (n = 14) were studied before, during, and after surgery. RESULTS: Measurement of plasma metanephrines and plasma and urinary catecholamines provided 100% and 82% sensitivity, respectively, for the detection of pheochromocytoma (P<.001). Levels of plasma catecholamines but not metanephrines increased in response to change of posture (norepinephrine, P =.03; epinephrine, P =.07) and intraoperative stress (norepinephrine, P =.002; epinephrine, P =.009). CONCLUSIONS: Plasma metanephrines offer improved efficacy for the diagnosis of pheochromocytoma. Less variability in response to external factors may favor plasma metanephrines in the screening for this disease. Arch Intern Med. 2000;160:2957-2963

Adrenal Gland Neoplasms↗
PubMed2000

[Focal proliferation in reactive hyperplastic parathyroid tissue in end-stage renal failure--implication for autotransplantation after total parathyroidectomy].

Total parathyroidectomy with simultaneous autotransplantation may be associated with recurrence of graft-dependent hyperfunction due to excessive proliferation. We performed macroscopic tissue selection with a stereomicroscope prior to autotransplantation, which resulted in very low recurrence rates. As this technique greatly depends on experience, we investigated the possibility of additionally using proliferation staining (PCNA, MIB-1) for the detection of dysfunctional tissue. Selected tissue from 26 patients was investigated. Serial sections of freshly removed parathyroid tissue were correlated with their macroscopic appearance, HE and immunohistochemically stained paraffin sections, and with semithin Epon sections. The asymptotic growth mode of clonal proliferating regions was reflected by highest staining intensity (1-5%) in small to medium sized foci (diffuse, up to 3 mm in diameter) and very low staining in large areas (diffuse or nodular, 5-15 mm in diameter, from 0.03 to 0.003% positive cells). Thus, very large dysfunctional regions with (almost) no proliferation could not be detected by this method. However, they were very evident on macroscopic investigation. In conclusion, multiple fulminant recurrence after parathyroidectomy can be prevented by selecting tissue after proliferation staining. This may allow a delayed autotransplantation after total parathyoidectomy for those surgeons lacking experience in macroscopic tissue classification.

Adult↗
PubMed2000

[Glomus caroticum chemodectoma. Review on current diagnosis and therapy].

Carotid body tumors are rare neoplasms arising from the small chemoreceptor organ in the adventitia of the common carotid bifurcation. Patients with carotid body tumours usually present with a gradually enlarging non-tender anterolateral neck mass. Differential diagnosis includes metastatic lymph nodes, carotid artery aneurysm, salivary gland tumour, branchial cleft cyst, and neurogenic or thyroid tumours. When such a lesion is suspected, a non-invasive Doppler colour flow ultrasonography enables the clinician to arrive at a definite diagnosis. Subsequent arteriography is mandatory, because the finding of an intensely blushing hypervascular mass spreading into the carotid bifurcation further supports the diagnosis and provides accurate preoperative information concerning arterial blood supply. Computed tomography scanning is appropriate to delineate the relation of the tumour to adherent structures, while magnetic resonance tomography demonstrates the relation of the tumour to the adjacent internal jugular vein and the carotid artery. Selective embolization should be performed for safe surgical removal with less bleeding. Early surgery is the treatment of choice and is recommended in order to minimize major risks. Subadventitial resection is the most established technique. Radical resection prevents local recurrence and has the best long-term results. Removal of the internal or common carotid arteries can become mandatory in selected cases of extensive disease. Surgical treatment by an experienced team is associated with considerably low mortality and morbidity.

Adult↗
PubMed2000

Is the new classification of neuroendocrine pancreatic tumors of clinical help?

A new concept of classifying neuroendocrine pancreatic tumors based on clinicopathologic patterns was summarized recently. To evaluate the clinical reliability and prognostic specificity of this classification system, 100 neuroendocrine pancreatic tumors were retrospectively categorized as "benign," "uncertain," and "malignant" based on tumor risk factors (size, local invasion and angioinvasion, cell atypia, metastases) and were followed for disease recurrence and progression. Altogether, 71 functioning tumors (insulinoma, gastrinoma, glucagonoma, enterochromaffin-like (ECL)oma, somatostatinoma) and 29 nonfunctioning neuroendocrine pancreatic tumors (NETs) were studied. NETs had an increased risk of malignancy (p < 0.05). Tumor size, gross invasion, and metastases correlated significantly with tumor behavior and allowed us to distinguish between "benign" and "malignant" tumors. About 89% of the tumors < or = 20 mm were "benign," whereas 71% > 20 mm were "malignant" (p < 0.05). In patients with "benign" and "uncertain" neuroendocrine pancreatic tumors, neither recurrence nor progression of disease was seen. About 41% of the patients with "malignant" tumors died of the disease. The 5-year estimated cumulative survival of those with "benign" and "uncertain" tumors was 100% and 52 +/- 10% for those with "malignant" tumors (p < 0.05). Histomorphologic details classifying the behavior of an "uncertain" tumor are known only after initial treatment and definitive histopathologic investigation. Thus this information is of limited clinical help for treatment strategies.

Adolescent↗
PubMed2000

Effects of successful parathyroidectomy on altered arterial reactivity in patients with hypercalcaemia: results of a 3-year follow-up study.

OBJECTIVE: Serum calcium was found to be an independent, prospective risk factor for myocardial infarction. We have previously shown that altered arterial reactivity in the course of primary hyperparathyroidism, a disease characterized by hypercalcaemia, may predominantly involve the arterial media and not the endothelium as observed in patients with various stages of atherosclerosis. The present study was performed to test whether successful parathyroidectomy can improve vascular reactivity in patients with primary hyperparathyroidism. SUBJECTS AND DESIGN: Endothelium-dependent, flow-mediated and endothelium-independent, nitroglycerin-induced dilatation were assessed by brachial artery ultrasound (7 MHz) in 18 patients with primary hyperparathyroidism (mean +/- SD; age, 55.1 +/- 12.6) prior to and 3 years after successful parathyroidectomy. RESULTS: Parathyroidectomy resulted in significant decreases of PTH (242 +/- 186 vs. 34 +/- 24 ng/l, P = 0. 0001) and serum calcium levels (2.8 +/- 0.3 vs. 2.4 +/- 0.1 mm/l, P = 0.00001) and in an increase of serum phosphate levels (0.78 +/- 0. 23 vs. 1.17 +/- 0.18 mm/l, P = 0.00001). However, normalization of hormone and electrolyte levels did not lead to an improvement of flow-mediated dilatation (12.1 +/- 3.1 vs. 11.0 +/- 5.4&, P = 0.49) or nitroglycerin-induced dilatation (12.5 +/- 3.1 vs. 13.2 +/- 6.8%, P = 0.68) within the follow-up period. No changes were observed with respect to the risk factor profile, vessel size and blood flow. CONCLUSION: These data suggest that restoration of normocalcaemia by parathyroidectomy cannot improve vascular reactivity in patients with primary hyperparathyroidism but may prevent further progression of vascular disease within this period of time.

Aged↗
PubMed2000

Risk factors for malignancy of thyroid nodules initially identified as follicular neoplasia by fine-needle aspiration: results of a prospective study of one hundred twenty patients.

Indeterminate or suspicious findings on fine-needle aspiration (FNA) of nodular thyroid disease (i.e., findings that neither give immediate indication for surgery nor lead to clear-cut conservative management) have been the key diagnostic problem in thyroid cytology for which the inability to differentiate cytologically benign from malignant follicular growth has been one reason. The aim of this cohort study of 120 consecutive (103 females, 17 males) patients with palpable nodular thyroid disease diagnosed as follicular neoplasia (FN) by FNA (defined by the triad of high numbers of follicular cells, microfollicular arrangement, and scanty or absent colloid) was to identify patients at high risk for malignancy based on the prospective evaluation of clinical features and to characterize the histologic entities of FN. Based on a 100% surgery rate we found an 18% malignancy rate (12 papillary carcinomas, 9 follicular carcinomas). Previously suggested factors with elevated risk for malignancy such as extremes of age, male gender, and large nodule size were not associated with increased risk as were cold nodules by 99mTc-scintigraphy (relative risk: 1.2, 95% confidence interval [CI] 0.4-3.3). However, hard lesions to palpation (relative risk 2.6, 95% CI: 1.2-5.6), solitary (relative risk: 2.6, 95% CI: 1.7-4.0), and hypoechoic FNs (relative risk: 3.4, 95% CI: 2.0-5.7) by ultrasound showed elevated risks of malignancy. In summary, suspicious palpation or ultrasound results may help to define a subgroup of patients with elevated risk of malignancy when FNA indicates the diagnosis of follicular neoplasm of the thyroid.

Adenocarcinoma, Follicular↗
PubMed2000

Prevalence of C-cell hyperplasia in patients with normal basal and pentagastrin-stimulated calcitonin.

The prevalence of thyroid C-cell hyperplasia (CCH) was investigated prospectively in 57 patients with normal preoperative pentagastrin-stimulated plasma concentrations of calcitonin (hCT, range, 1-60 pg/mL; normal, 100 pg/mL) who subsequently underwent total thyroidectomy due to thyrotoxicosis (n = 18) or to nodular thyroid disease in the presence (n = 9) or absence (n = 30) of cytological follicular neoplasia. CCH was seen in 28 of 57 (49%) of all patients. CCH was more common in hyperthyroid (12/18 [66%]) than in euthyroid (16/39 [41%] patients. No age- or gender-related differences in the occurrence of CCH was seen. There was no histological evidence of medullary thyroid carcinoma (MTC) in any patient. CCH classified histologically as neoplastic was encountered in two instances. It was concluded that CCH may be expected in almost 50% of normocalcitonemic patients with various thyroid disorders. Although the potential clinical importance of this histological finding and specifically its neoplastic variety remains unknown, these results are in keeping with the assumption that pentagastrin-stimulated plasma concentrations of hCT within the normal range do not exclude the presence of CCH.

Adult↗
PubMed2000

Advanced insular thyroid carcinoma in a fourteen-year-old girl: twenty-four years of follow-up.

Insular thyroid carcinoma has become a separate entity among thyroid malignancies. It is regarded as intermediate in aggressiveness between well-differentiated and anaplastic thyroid carcinomas. Reports on the clinical course of children with insular thyroid carcinoma are rare. We report the case of a 14-year-old girl who was admitted to our thyroid outpatient ward in 1975 with a scintigraphic cold thyroid nodule and multiple enlarged cervical lymph nodes. Chest radiography showed metastases in both lungs. After total thyroidectomy and, central and modified unilateral radical neck dissection, the girl was given a dose of 80 mCi 131I. Posttherapeutic scan demonstrated diffuse tracer uptake in both lungs. A second dose of 200 mCi 131I was administered 4 months later and another dose of 150 mCi 131I in July 1976. Subsequently, whole-body scans showed inconspicuous tracer distribution and chest x-rays were normal. The patient was treated with levothyroxine and followed until 1982, when she left Vienna. In 1999, the patient was contacted for reexamination. She has been well and had had two healthy children. The patient was taking 150 microg levothyroxine daily; she had a normal TSH value and her thyroglubulin was 0.3 ng/mL. Chest radiography and sonography of the neck showed no pathological findings. The paraffin sections of the patient's tumor were reexamined in 1999 and demonstrated the histologic characteristics of a poorly differentiated insular thyroid carcinoma (pT4a, pN1a, M1). These findings demonstrate that even in advanced stages, insular thyroid carcinoma treatment can be successful.

Adolescent↗
PubMed2000

Value of peptide receptor scintigraphy using (123)I-vasoactive intestinal peptide and (111)In-DTPA-D-Phe1-octreotide in 194 carcinoid patients: Vienna University Experience, 1993 to 1998.

PURPOSE: To report our experience with both (123)I-vasoactive intestinal peptide (VIP) and (111)In-DTPA-D-Phe(1)-octreotide for imaging to identify primary and metastatic tumor sites in carcinoid patients. PATIENTS AND METHODS: One hundred ninety-four patients with a verified or clinically suspected diagnosis of a carcinoid tumor were injected with (111)In-DTPA-D-Phe(1)-OCT for imaging purposes, while 133 patients underwent scanning with both (123)I-VIP and (111)In-DTPA-D-Phe(1)-OCT in random order. Imaging results were compared with computed tomography scans, results of conventional ultrasound, endosonography, and endoscopy, and results of surgical exploration in case of inconclusive conventional imaging. RESULTS: Primary or recurrent carcinoid tumors could be visualized with (111)In-DTPA-D-Phe(1)-OCT in 95 (91%) of 104 patients; metastatic sites were identified in 110 (95%) of 116 patients. In 11 (51%) of 21 patients with suggestive symptoms but without identified lesions by conventional imaging, focal tracer uptake located the carcinoid tumor. In addition, metastatic disease was demonstrated in three patients after resection. In a direct comparison in the 133 patients who underwent both imaging modalities, (111)In-DTPA-D-Phe(1)-OCT was found to be superior to (123)I-VIP, with 35 (93%) of 38 versus 32 (82%) of 38 scans being positive in primary or recurrent tumors, 58 (90%) of 65 versus 53 (82%) of 65 being positive in patients with metastatic sites, and seven (44%) of 16 versus four (25%) of 16 being positive in patients with symptoms but otherwise negative work-ups. Overall, additional lesions not seen on conventional imaging were imaged in 43 (41%) of 158 versus 25 (25%) of 103 scans with (111)In-DTPA-D-Phe(1)-OCT and (123)I-VIP, respectively. CONCLUSION: Both peptide tracers have a high sensitivity for localizing tumor sites in patients with ascertained or suspected carcinoid tumors, with (111)In-DTPA-D-Phe(1)-OCT scintigraphy being more sensitive than (123)I-VIP receptor scanning. Both, however, had a higher diagnostic yield than conventional imaging, as verified by surgical intervention or long-term follow-up. The combination of both peptide receptor scans does not seem to further enhance diagnostic information.

Adult↗