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K Scheidhauer

Publications and source records attributed to K Scheidhauer.

At least 19 recordsLinked to original sources
PubMed2006

Radio-guided surgery for persistent differentiated papillary thyroid cancer: case presentations and review of the literature.

BACKGROUND AND AIMS: Persistent differentiated papillary thyroid cancer following radical locoregional surgery with metastases is an indication for limited reoperation or radioiodine therapy. Following injection of radioiodine, radio-guided surgery with application of an intraoperative gamma probe offers detection of metastases not seen by conventional imaging and control of completeness of resection. PATIENTS/METHODS: We demonstrate four patients with locoregional metastases, two of them with additional distant metastases of papillary thyroid cancer following radical neck surgery. Postoperative radioiodine scans demonstrated persistent ipsilateral or contralateral cervical and mediastinal lymph node and isolated rib metastases. RESULTS: Radio-guided surgery (RGS) leads to complete clearance of persistent lymph node metastases by limited recurrent neck surgery, resection of metastases not seen by conventional imaging and control of complete mediastinal lymph node dissection. Post-RGS scans allowed early diagnosis of occult diffuse or nodal pulmonary metastases in two patients. At last follow-up, 23 to 48 months following RGS and radioiodine therapy, there was no evidence of disease. CONCLUSIONS: Radio-guided surgery is an additive surgical technique with low morbidity in selected patients with persistent thyroid cancer individualizing tumor therapy options in multimode oncological therapy.

Adolescent↗
PubMed2005

[Scintigraphic procedures in internal medicine--indications, limits, possibilities].

Scintigraphy continues to play an important diagnostic role in internal medicine. Many diagnostic questions can only be answered with scintigraphic methods. The application of specific radiopharmaceutical tracers offers the unique possibility to visualize ongoing functional changes, associated with diseases concerning internal medicine. The diagnostic potential of modern scintigraphic procedures such as PET for internal medicine is not yet sufficiently used and will continue to grow with hybrid systems, such as PET-CT and SPECT-CT.

Adolescent↗
PubMed2005

[Reoperation for thyroid cancer].

Reoperation for thyroid cancer needs to consider patient-, tumor- and therapy-related aspects as well as present diagnostic results. Reoperation because of thyroid remnants, persistence of the primary tumor and lymph node metastasis (completion surgery) has to be distinguished from reoperation due to locoregional recurrence (primary tumor, lymph nodes). The primary surgical strategy should avoid the need for reoperation. The extent of reoperation is related to the extent of primary surgery, stage, and distant metastasis. The timing and indication of reoperation for differentiated thyroid carcinoma in an interdisciplinary multimodal treatment setting depends on diagnostic radioiodine scans and radioiodine therapy. Long-term, recurrence-free survival is achieved by sufficiently radical surgery with acceptable morbidity, including all additive or adjuvant treatment options.

Disease Progression↗
PubMed2004

FDG PET and other imaging modalities in the primary diagnosis of suspicious breast lesions.

Mammography is the primary imaging modality for screening of breast cancer and evaluation of breast lesions (T staging). Ultrasonography is an adjunctive tool for mammographically suspicious lesions, in patients with mastopathy and as guidance for reliable histological diagnosis with percutaneous biopsy. Dynamic enhanced magnetic resonance mammography (MRM) has a high sensitivity for the detection of breast cancer, but also a high false positive diagnosis rate. In the literature, MRM is reported to have a sensitivity of 86-96%, a specificity of 64-91%, an accuracy of 79-93%, a positive predictive value (PPV) of 77-92% and a negative predictive value (NPV) of 75-94%. In unclarified cases, metabolic imaging using fluorine-18 fluorodeoxyglucose positron emission tomography (FDG PET) can be performed. In the literature, FDG PET is reported to have a sensitivity of 64-96%, a specificity of 73-100%, an accuracy of 70-97%, a PPV of 81-100% and an NPV of 52-89%. Furthermore, PET or PET/CT using FDG has an important role in the assessment of N and M staging of breast cancer, the prediction of tumour response in patients with locally advanced breast cancer receiving neoadjuvant chemotherapy, and the differentiation of scar and cancer recurrence. Other functional radionuclide-based diagnostic tools, such as scintimammography with sestamibi, peptide scintigraphy or immunoscintigraphy, have a lower accuracy than FDG PET and, therefore, are appropriate only for exceptional indications.

Breast Neoplasms↗
PubMed2003

Clinical and diagnostic value of preoperative MR mammography and FDG-PET in suspicious breast lesions.

Dynamic enhanced magnetic resonance (MR) mammography and fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) of the breast were directly compared preoperatively in suspicious breast lesions. Forty-two breast lesions in 40 patients were examined with a three-dimensional dynamic MR imaging series and FDG-PET. The MR and PET examinations were evaluated separately and the results were compared with the histological findings. The sensitivity and specificity of each method were calculated. The diagnostic value of both modalities as single diagnostic tool and in combination was investigated. Nineteen malignant and 23 benign breast lesions were proven histologically. Magnetic resonance mammography and FDG-PET showed a sensitivity of 89 and 63%, respectively. The specificity was 74 and 91%, respectively. The combination of both imaging methods decreased the not-required biopsies from 55 to 17%. Only one false-negative finding-a patient pre-treated with chemotherapy-was observed in both methods. The combination of MR mammography and FDG-PET can help to decrease biopsies of benign breast lesions. Because of their high cost, these modalities should only be used in problematic cases to either rule out or to demonstrate malignancy. The best diagnostic strategy is achieved using MR mammography first. If the diagnosis is still questionable, FDG-PET can be performed.

Breast↗
PubMed2002

PET imaging of somatostatin receptors: design, synthesis and preclinical evaluation of a novel 18F-labelled, carbohydrated analogue of octreotide.

Because of the excellent nuclear properties of fluorine-18 and the growing interest in somatostatin receptor (sst) scintigraphy with PET, a novel carbohydrated (18)F-labelled sst ligand was developed and preclinically evaluated. Synthesis of N(alpha)-(1-deoxy- D-fructosyl)- N(epsilon)-(2-[(18)F]fluoropropionyl)-Lys(0)-Tyr(3)-octreotate ([(18)F]FP-Gluc-TOCA) was completed in approximately 3 h (20%-30% yield). [(19)F]FP-Gluc-TOCA showed no affinity to hsst1 and hsst3, moderate affinity to hsst4 (IC(50): 437+/-84 n M) and hsst5 (IC(50): 123+/-8.8 n M) and very high affinity to hsst2 (IC(50): 2.8+/-0.4 n M). As a result of carbohydration, lipophilicity of [(18)F]FP-Gluc-TOCA was found to be low (lg P(OW)=-1.70+/-0.02). In mice, the tracer was rapidly cleared via renal excretion (kidneys: 8.69%+/-1.09%ID/g) and showed low uptake in liver (0.72%+/-0.14%ID/g) and intestine (1.88%+/-0.52%ID/g) and high tumour uptake (13.54%+/-1.47%ID/g) (all data at 1 h p.i.). Tumour to non-tumour ratios at 60 min p.i. reached 25, 19, 7, 1.6 and 56 for blood, liver, intestine, kidney and muscle, respectively. A similar biodistribution pattern was observed in pancreatic tumour-bearing rats. Tumour uptake in rats was reduced to 36% and 18% of control (30 and 60 min) by co-injection of 500 microg Tyr(3)-octreotide, demonstrating sst-specific uptake. In a first [(18)F]FP-Gluc-TOCA-PET study of a patient with a metastatic carcinoid in the liver the tracer showed superior pharmacokinetics, e.g. rapid urinary excretion and low uptake in liver, kidney and spleen. Multiple liver lesions (SUVs ranging from 21.4 to 38.0) and previously unknown focal uptake in the abdomen (SUV 10.0) were clearly visible. This is the first report on PET imaging using an (18)F-labelled sst binding peptide; it indicates that [(18)F]FP-Gluc-TOCA offers excellent imaging characteristics and allows sst imaging with high tumour to non-tumour contrast.

Aged↗
PubMed2002

[Body weight gain after radioiodine therapy in hyperthyroidism].

AIM: Analysis and follow up of body weight after radioiodine therapy (RITh) of hyperthyroidism, since excessive weight gain is a common complaint among these patients. METHODS: Therapy and body weight related data of 100 consecutive RITh-patients were retrospectively analysed from the time before up to three years after RITh. All patients suffered from hyperthyroidism (Graves' disease or autonomy), but were adjusted to euthyroid levels after RITh. Patients' data were compared to a control group of 48 euthyroid patients out of the same ambulance and during the same time scale. RESULTS: All patients (RITh and controls) gained weight over the time. There was no statistically significant difference in BMI development over three years between RITh-patients and controls (5.5% resp. 4.9% increase). In the first year after RITh, weight gain of the RITh patients was higher indeed, but lower in the follow up, resulting in the same range of weight gain after three years as the controls. Besides that women showed a slightly higher increase of BMI than men, and so did younger patients compared to elder as well as patients with overweight already before RITh. CONCLUSIONS: An initially distinct increase of body weight after RITh of hyperthyroidism is mainly a compensation of pretherapeutic weight loss due to hyperthyroidism. Presupposing adequate euthyroid adjustment of thyroid metabolism after therapy, RITh is not responsible for later weight gain and adipositas.

Adult↗
PubMed2001

Whole-body positron emission tomography using 18F-fluorodeoxyglucose for initial staging of patients with Hodgkin's disease.

An accurate initial staging of patients with Hodgkin's disease (HD) is important for the evaluation of clinical stage and risk factors, which are crucial for the choice of an appropriate treatment. 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) is useful for detecting active tumor tissue in patients with lymphoproliferative diseases and may contribute to conventional staging methods in patients with HD. Twenty-two patients who presented with newly diagnosed HD underwent conventional staging methods including computed tomography (CT) as well as FDG PET. Lesions apparent in FDG PET and CT were correlated to each other. Seventy-seven lesions were observed either in PET or CT or in both. In 48 (62%) lesions PET and CT were both positive. In 20 (26%) sites, PET was positive and CT negative. Of 22 patients (18%) 4 were upstaged due to these positive PET findings, and as a result one patient received a different therapeutic regimen. PET failed to detect nine (12%) CT-positive sites in six patients. Statistically, these data are reflected by a sensitivity for PET and CT of 88% and 74%, respectively. Specificity of both imaging modalities was 100%. PET can contribute valuable information as an additional staging examination and led to an upstaging in some patients with primary HD. However, PET should not be used as the only imaging modality as it failed to detect CT-positive, active tumor regions in some cases.

Adult↗
PubMed2001

Thoracic positron emission tomography using 18F-fluorodeoxyglucose for the evaluation of residual mediastinal Hodgkin disease.

Residual mediastinal masses are frequently observed in patients with Hodgkin disease (HD) after completed therapy, and the discrimination between active tumor tissue and fibrotic residues remains a clinical challenge. We studied the diagnostic value of metabolic imaging by 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in detecting active mediastinal disease and predicting relapse. Twenty-eight HD patients with a residual mediastinal mass of at least 2 cm after initial therapy or after salvage chemotherapy were prospectively assigned to 29 examinations with FDG PET and were evaluated as 29 "subjects." Patients were monitored for at least 1 year after examination and observed for signs of relapse. Median follow-up was 28 months (range, 16 to 68 months). A PET-negative mediastinal tumor was observed in 19 subjects, of whom 16 stayed in remission and 3 relapsed. Progression or relapse occurred in 6 of 10 subjects with a positive PET, whereas 4 subjects remained in remission. The negative predictive value (negative PET result and remission) at 1 year was 95%, and the positive predictive value (positive PET result and relapse) was 60%. The disease-free survival for PET-negative and PET-positive patients at 1 year was 95% and 40%, respectively. The difference was statistically significant. A negative FDG PET indicates that an HD patient with a residual mediastinal mass is unlikely to relapse before 1 year, if ever. On the other hand, a positive PET result indicates a significantly higher risk of relapse and demands further diagnostic procedures and a closer follow-up.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2001

Metabolic activity and clinical features of primary ganglioneuromas.

BACKGROUND: Ganglioneuroma (GN) is considered by most to be a benign tumor of neural crest origin. It may evolve from differentiating neuroblastoma or may be diagnosed as primary ganglioneuroma. The rarity of this tumor and the lack of understanding of its biology often lead to inaccurate diagnosis and treatment. METHODS: The authors analyzed clinical features and biologic behavior of primary ganglioneuroma in 49 patients who were registered with but were not part of the national neuroblastoma trials. Data included age and symptoms at diagnosis, gender, tumor localization and size, (123)I-metaiodobenzylguanidine (mIBG) scintigraphy, secretion of catecholamines, histology, treatment, and outcome, whenever available. RESULTS: Patients with primary ganglioneuroma were significantly older than patients with neuroblastoma. Median age at diagnosis was 79 months compared with 16 months (P < 0.0001). Ganglioneuroma were equally distributed between males and females (1.13:1). A preference of thoracic (41.5%) and abdominal, nonadrenal tumors (37.5%) was observed compared with adrenal GN (21%). At diagnosis, thoracic tumors appeared larger than nonthoracic ones. Local lymph node metastases occurred in two patients. One ganglioneuroma had metastasized to soft tissues. (123)I-mIBG scintigraphy detected mIBG uptake at tumor site in 57% of the GN tumors. Levels of catecholamines in plasma and/or urine were increased in 39%. Slight immaturity of ganglion cells was observed in 93% of all ganglioneuroma tumors. None of the 22 tumors analyzed exhibited MYCN gene alterations. Although 12 patients had macroscopic residuals, no tumor progression or recurrence was observed in a median follow-up of 25 months. CONCLUSIONS: Ganglioneuroma may present with metabolic activity such as increased secretion of catecholamines and/or mIBG uptake. There are no specific diagnostic signs or symptoms discriminating ganglioneuroma and neuroblastoma tumors. Therefore, ganglioneuroma requires tissue investigation for diagnosis. Prognosis after surgical resection without further therapy seems to be excellent.

3-Iodobenzylguanidine↗
PubMed2000

2[F]-fluoro-2-deoxy-D-glucose positron emission tomography is a sensitive tool for the detection of occult primary cancer (carcinoma of unknown primary syndrome) with head and neck lymph node manifestation.

BACKGROUND: The neck lymph nodes are a common site of metastases from carcinoma of unknown primary (CUP syndrome). 2[(18) F]-fluoro-2-deoxy-D-glucose positron emission tomography (18-FDG-PET) has been shown to be a sensitive tool for detecting primary malignant lesions as well as metastatic spread. We have prospectively investigated the sensitivity of 18-FDG-PET in detecting occult primary carcinomas with manifestation in the head and neck lymph nodes. METHODS: From May 1994 to July 1998, in 723 patients a cancer of the head and neck was diagnosed at the University of Cologne ENT outpatient clinic. The routinely performed staging procedures were chest radiography; full blood count; cervical and liver ultrasound; endoscopy of the nasopharynx, oropharynx, hypopharynx, larynx, and esophagus; and laboratory analyses. After the staging workup, in 27 of 723 patients (3.7%) CUP syndrome had to be presumed because the primary cancer could not be detected. In these patients 18-FDG-PET was performed, and images were reconstructed with a transmission-emission fusion technique. RESULTS: In 7 of 27 patients (26%) 18-FDG-PET revealed an unknown primary: in 2 a bronchial carcinoma, in 2 a nasopharyngeal carcinoma, in 1 a squamous cell carcinoma of the parotid gland, in 1 a squamous cell carcinoma of the hypopharynx, and in 1 a carcinoma of the tonsil. In 4 of 7 patients the occult primary tumor was removed surgically. In 8 of 27 patients therapeutic strategy was changed as a result of the 18-FDG-PET findings. CONCLUSION: 18-FDG-PET should be performed in all patients with CUP syndrome after conventional diagnostic workup fails to identify the primary.

Adenocarcinoma↗
PubMed2000

Fluor-18-fluorodeoxyglucose positron emission tomography (FDG-PET) in malignant melanoma. Diagnostic comparison with conventional imaging methods.

PURPOSE: To assess the diagnostic value of fluor-18-fluorodeoxyglucose positron emission tomography (FDG-PET) in screening for melanoma metastases. MATERIAL AND METHODS: The case records of 94 melanoma patients who had been examined by whole-body FDG-PET between 1995 and 1999 were evaluated retrospectively. Forty patients showed evidence of lymphogenous and 42 of hematogenous metastasis. The maximal interval between PET and the diagnostic procedure under comparison was 2 weeks. Confirmation of the findings was based on histology or the clinical or radiological course. RESULTS: In 24 patients, all diagnostic examinations including CT had been performed within 2 weeks from PET. In no case did PET change the staging. In 13 patients, PET agreed with morphological diagnosis in the number of metastatically invaded organs. This included 3 patients without metastases. The estimated number of organs invaded by metastases was higher with PET in 5 patients and higher with morphological imaging techniques in 6 patients. Among the PET findings with higher or equivocal counts of organs with metastases there were 2 confirmed false-positive findings. CONCLUSION: In a selected patient population, FDG-PET was found to be inferior to CT for diagnosing lung and liver metastases. The supplementary use of FDG-PET is not generally of value once metastasis has been established.

Abdomen↗
PubMed2000

Hypothyroidism after therapy for larynx and pharynx carcinoma.

Early detection of local and regional recurrence is the main goal during follow-up of patients with larynx and pharynx cancer. Hypothyroidism occurring in those patients stays frequently undiagnosed as screening for hypothyroidism is not part of the routine follow-up. This study was performed to assess the prevalence of hypothyroidism in these patients. We included 120 patients (106 male, 14 female) with larynx or pharynx cancer treated more than 2 months earlier (mean = 41 months) in the study. Cancer treatment consisted of either surgery (n = 44), radiotherapy (n = 15), or surgery combined with postoperative radiotherapy (n = 61). In all patients, thyroid function studies (thyrotropin [TSH], free triiodothyronine [FT3], and free thyroxine [FT4]) were performed. Twenty-six of all patients (22%) were hypothyroid; in two patients hypothyroidism was diagnosed postoperatively and these two patients were on replacement therapy with thyroid hormones. The highest rate of hypothyroidism (34%) was present in patients treated with surgery combined with radiotherapy, whereas among patients treated with surgery only 7% were hypothyroid (p < 0.001). There was no difference in the duration of follow-up between therapy and inclusion in the study between those two groups. Two of 15 patients treated only with radiotherapy were diagnosed hypothyroid, but in this group the latency was shorter (p < 0.05). The results indicate that thyroid function studies should be routinely performed in the follow-up of head and neck cancer patients, especially if radiotherapy was part of the treatment.

Aged↗
PubMed2000

Follow-up of differentiated thyroid cancer: comparison of multiple diagnostic tests.

The radioablation of thyroid remnants improves the prognosis of differentiated thyroid cancer. In our prospective study an activity of 3.7 GBq 131I failed to completely ablate the remnants in 46 out of 101 patients, but a 3-year follow-up period was uneventful. One other patient had a recurrence early after thyroidectomy. In view of possible stunning effects of 131I it might be advantageous to visualize such remnants by imaging modalities which do not emit beta-particles. Our data have revealed that neither magnetic resonance imaging (MRI), nor ultrasonography (US), nor 99Tcm-sestamibi scintigraphy, nor positron emission tomography could detect or reliably exclude minimal remnants. Such remnants did not produce thyroglobulin (Tg). A 123I and 131I uptake of> 10% after thyroidectomy was associated with about a 90% probability of persistent remnants. On the other hand, MRI was helpful in the patient group (n = 32) with Tg>4ng x ml(-1) at the second whole-body scintigraphy (TSH>30 mU x l(-1)) for planning the management of lymph node metastases (n = 15 patients): 12 patients had subsequent surgery and three patients radioiodine therapy. We recommend that MRI be used early in follow-up care when Tg is elevated. The decision of whether or not to treat persistent thyroid remnants should not be made on the basis of MRI, US or nonspecific scintigraphic methods. Complete ablation did not appear to have any clinical benefit in our study group.

Adolescent↗
PubMed1999

Fluorine-18 fluorodeoxyglucose positron emission tomography in thyroid cancer: results of a multicentre study.

The aim of this multicentre study was to evaluate the clinical significance of fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) in differentiated thyroid carcinoma and to compare the results with both iodine-131 whole-body scintigraphy (WBS) and technetium-99m 2-methoxyisobutylisonitrile (MIBI) or thallium-201 chloride (Tl) scintigraphy. Whole-body PET imaging using FDG was performed in 222 patients: 134 with papillary tumours, 80 with follicular tumours and 8 with mixed-cell type tumours. Finally, for each case an overall clinical evaluation was done including histology, cytology, thyroglobulin level, ultrasonography, computed tomography and subsequent clinical course, to allow a comparison with functional imaging results. Sensitivity of FDG-PET was 75% and 85% for the whole patient group (n = 222) and the group with negative radioiodine scan (n = 166), respectively. Specificity was 90% in the whole patient group. Sensitivity and specificity of WBS were 50% and 99%, respectively. When the results of FDG-PET and WBS were considered in combination, tumour tissue was missed in only 7%. Sensitivity and specificity of MIBI/Tl were 53% and 92%, respectively (n = 117). We conclude that FDG-PET is a sensitive method in the follow-up of thyroid cancer which should be considered in all patients suffering from differentiated thyroid cancer with suspected recurrence and/or metastases, and particularly in those with elevated thyroglobulin values and negative WBS.

Female↗
PubMed1999

Positron emission tomography using 18F-fluorodeoxyglucose in advanced stages of malignant melanoma: a comparison of ultrasonographic and radiological methods of diagnosis.

The diagnostic and therapeutic impact and the cost-effectiveness of positron emission tomography (PET) using 18F-fluorodeoxyglucose (FDG) will depend on the role for which the tests are used. In 68 patients with advanced malignant melanoma, original sets of FDG-PET images from various institutes were compared with findings obtained by ultrasonography, conventional radiology, computed tomography (CT) and magnetic resonance imaging. In 22 patients, all examinations were undertaken within 2 weeks and strategies of staging were analysed. In 46 patients, only some of these examinations were performed within this time period, and comparison of methods was restricted to the examined organs. The occurrence of metastasis, without specifying the number of foci, was detected by either conventional staging with CT or by PET in 20 of 22 patients. None of these patients were up- or down-staged by FDG-PET compared with CT staging. In the 68 patients as a whole, FDG-PET detected fewer pulmonary and hepatic metastases and fewer cerebral foci, but more lymph node and bone metastases than conventional radiology or CT. For the detection of lymph node or skeletal metastases, false-positive FDG-PET findings were taken into account when compared with follow-up data. In advanced melanoma, FDG-PET did not influence the pattern of subsequent diagnostic testing. Thus, indications for FDG-PET include pre-metastatic melanoma, localized lymph node metastases and monitoring of the response to treatment.

Adolescent↗