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S Lang

Publications and source records attributed to S Lang.

At least 55 records · Page 3Linked to original sources
PubMed2002

[Value of secondary coronal reconstructions in computed tomography of the paranasal sinuses].

INTRODUCTION: Before sinus surgery, computed tomography (CT) of the paranasal sinuses and anterior skull base is a standard procedure in the diagnostic evaluation. However, coronal sections necessary for the analysis of the complex anatomy of this region are often not applicable in multiple injured or elderly patients due to the impossibility to maintain the required position for the coronal scans. Secondary coronal reconstruction of primary axially acquired scans could help to overcome this problem. This technique was, however, hampered so far by an insufficient resolution in case of conventional CT. We therefore compared the quality of primary coronally acquired conventional CT images with the resolution of multiplanar reformatted coronal images of primary axially acquired scans by means of a new CT generation, the Multidetector Computed Tomography (MDCT). MATERIAL AND METHODS: 10 patients were each examined with conventional CT or MDCT respectively. The quality of primary coronally acquired conventional scans (CT) versus secondary coronal reconstructions (MDCT) was compared by evaluating typical anatomic landmarks. RESULTS: As compared to conventional CT, the coronal reconstruction of primary axially acquired scans by means of MDCT revealed an equal resolution and additionally no essential impairment by amalgam artefacts. CONCLUSION: Our results demonstrate the excellent quality of secondary coronal reconstructions by means of MDCT in the CT evaluation of the paranasal sinuses and the anterior skull base as compared to primary coronally acquired images via conventional CT.

Artifacts↗
PubMed2002

[Correlation of FDG-PET and MRI/CT with histopathology in primary diagnosis, lymph node staging and diagnosis of recurrency of head and neck cancer].

AIM: Correct staging of head and neck cancer is important for the patient's prognosis and further therapeutic strategies. Aim of the present study was to investigate the diagnostic value of FDG-PET regarding the pre-surgical diagnosis of primary tumor and cervical lymph node metastases, the diagnosis of tumour recurrence, and the localisation of unknown primary, further to compare the results to those of morphological imaging modalities (CT/MRI) and to correlate the results of both methods with histopathological findings. PATIENTS/METHODS: 115 patients (pts) (72 x primary diagnosis, 37 x recurrence, and 6 x unknown primary) underwent FDG-PET (ECAT EXACT HR+) and CT or MRI. Results were correlated with histopathological findings in terms of detection of primary and recurrent tumors as well as lymph node metastases. RESULTS: Regarding the pre-surgical diagnosis, sensitivity and specificity for identifying primary tumors were 85 % and 100 % for PET and 88 % and 75 % for CT/MRI, respectively. Accuracy was 86 % for PET and 87 % for CT/MRI. Sensitivity and specificity for detecting primary lymph node involvement were 71 %/86 % for PET and 74 %/57 % for CT/MRI, resulting in an accuracy of 77 % with PET and 68 % with morphological imaging. In 23 pts histopathology revealed pT1 stages with tumor diameters < 12 mm. In 8 pts CT/MRI and in 10 pts PET failed to identify these small primary lesions. Detecting tumor recurrence (n = 37) PET showed a higher sensitivity (83 %), specificity (76 %) and accuracy (78 %) compared to CT/MRI (sensitivity: 67 %; specificity: 52 %; accuracy: 57 %). In 4/6 pts with unknown primary, imaging was able to identify a primary lesion (3/4 in FDG-PET, 2/4 in CT/MRI), in 2/6 patients even in the follow-up no primary tumor was found. CONCLUSIONS: FDG-PET provides only minor additional information to morphological imaging concerning diagnosis of primary tumors. At a similar level of sensitivity, however, it seems to be more specific regarding the lymph node involvement. PET seems to be superior to CT/MRI in detecting tumor recurrence as well as occult primary tumors in pts with known cervical lymph node metastases.

Adult↗
PubMed2002

[Clinical and epidemiological data of patients with malignomas of the head and neck].

BACKGROUND: The present study describes clinical and epidemiological data of patients with malignomas of the head and neck documented in the Munich Cancer Register. PATIENTS AND METHODS: Data of head and neck cancer patients treated at four departments of head and neck surgery and one of oral-maxillo-facial surgery in the area of Munich from 1978 up to now are reported. RESULTS: Incidence and mortality as a function of age, sex, and tumor localization are described in comparison to clinical and epidemiological data as specified in tumor registers of the Saarland and the USA. Moreover, TNM stages, survival, recurrence, and metastasis rates are presented. CONCLUSION: Based on the documentation of the Munich Cancer Register our study is the first to present a detailed description of clinical and epidemiological data of patients suffering from head and neck malignomas.

Adult↗
PubMed2002

[The expression of zeta-chain of the T cell receptor as prognostic marker for patients with head and neck cancer].

INTRODUCTION: The zeta-chain as an important component of the T cell receptor (TCR) is involved in the transduction of intracellular signals and is therefore critical for T cell activation and subsequent induction of an anti-tumor response. In patients with squamous cell carcinoma of the head and neck (SCCHN) several mechanisms of immune suppression have been described. The expression of the TCR zeta-chain of both peripheral blood lymphocytes (PBLs) and tumor infiltrating lymphocytes (TILs) has been analysed in patients with SCCHN and correlated to clinical data. METHODS: TIL and PBL from 47 patients with SCCHN were obtained. To determine expression of the zeta-chain in both PBLs and TILs, double immunostaining with mAbs and flow cytometric analysis was performed. The technique combined an intracellular staining with a surface staining. RESULTS: As compared to healthy controls (n = 23), zeta-chain expression was significantly reduced (p < 0.002) in patients with SCCHN (n = 23) with lowest expression in those with UICC VI disease. Our results show a tight correlation between the loss of zeta-chain expression and the clinical aggressiveness of the tumor. Higher tumor stages frequently show a higher loss of the zeta-chain. In 11 patients zeta-chain expression of the PBL could be compared with TIL. Independent of the tumor stage the loss of the zeta-chain expression is much higher in TIL than in PBL. The loss of the zeta-chain expression also correlates with the progression of the disease. Patients with a high loss of the zeta-chain expression develop a recurrence more frequently. CONCLUSION: The loss of the zeta-chain documents a systemic immune defect, which even occurs in early tumor stages. Additionally to locoregional approaches future therapeutic strategies should also focus on systemic immunomodulation.

Biomarkers, Tumor↗
PubMed2002

The expression of bone morphogenetic proteins in osteosarcoma and its relevance as a prognostic parameter.

AIMS: The expression of bone morphogenetic proteins (BMPs) was analysed in 47 osteosarcomas to determine differences in the expression of BMP subtypes and to correlate expression with response to chemotherapy, in addition to the disease free and overall survival of patients. METHODS: The expression of BMPs was examined immunohistochemically in 47 biopsy specimens of osteosarcoma using commercially available antibodies against different subtypes (BMP-2/4 (A-20), BMP-3 (N-19), BMP-4 (N-19), BMP-5 (N-19), BMP-6 (N-19), BMP-7 (N-19), BMP-8 (N-19)). The avidin-biotin-immunoperoxidase method was used for all antibodies. RESULTS: The expression of BMP subtypes varied considerably: 28 of the 47 tumours expressed BMP-2/4, 24 expressed BMP-3, 41 expressed BMP-5, 31 expressed BMP-6, 43 expressed BMP-7, and 42 expressed BMP-8. High expression of BMP-6 was found in those parts of the osteosarcoma with a chondroid differentiation (p = 0.016, Mann-Whitney test). No correlation was observed between the response to chemotherapy and the expression of BMPs (p > 0.05, Mann-Whitney test). Univariate analysis showed no correlation between overall survival or progression free survival and the expression of BMPs (p > 0.05, log rank test). CONCLUSIONS: BMP-7 and BMP-8 are highly expressed in osteosarcoma. Moreover, high expression of BMP-6 correlates with a chondroid differentiation. In contrast to conclusions derived from previous studies in which small numbers of tumours were investigated, these results indicate that the expression of BMPs does not help to predict the outcome of patients.

Adolescent↗
PubMed2001

Event-related potentials in an auditory semantic oddball task in humans.

Whenever rare target stimuli are presented interspersed by frequent irrelevant stimuli (standards), the targets elicit a late parieto-central positive wave called P3. Usually standards and targets differ by a simple physical feature (e.g. tone pitch). Less consistent are the data obtained in semantic tasks, in which standards and targets are represented by different word classes. Given an equal number of words in the target and standard categories, each individual standard is more frequent than each target, that is, the frequency of the category is confounded with that of individual stimuli. In the present study participants were presented five semantic classes each being represented by 15 words. Words belonging to one particular class should be counted. Thus targets were rare (20%), although the frequencies of each word and of each semantic class were equal. A highly significant P3 was recorded. Its latency was longer, and the amplitude was smaller, than when standards and targets were two tones. These data indicate that brain waves recorded in semantic tasks are not necessarily manifestations of specific semantic processing.

Adult↗
PubMed2001

Impact of hemoglobin level and use of recombinant erythropoietin on efficacy of preoperative chemoradiation therapy for squamous cell carcinoma of the oral cavity and oropharynx.

PURPOSE: We assessed the influence of hemoglobin level and r-HuEPO administration on response to chemoradiotherapy, locoregional tumor control, and overall survival in patients treated with neoadjuvant chemoradiotherapy and surgery for a squamous cell carcinoma of the oral cavity or oropharynx. METHODS AND MATERIALS: The 191 study patients were treated with mitomycin C (15 mg/m(2) day 1), 5-fluorouracil (750 mg/m(2)/day, days 1-5), and radiotherapy (50 Gy in 25 fractions weeks 1-5), followed by resection of the primary tumor bed and neck dissection at the General Hospital Vienna, Austria, between November 1989 and October 1998 for a T2-4, N0-3, M0 SCC of the oral cavity or oropharynx. Starting in May 1996, patients with a low hemoglobin (Hgb) before or during chemoradiotherapy received r-HuEPO 10,000 IU/kg s.c. 3-6 times/week until the week of surgery. RESULTS: On multivariate analysis, Hgb level and use of r-HuEPO were independent prognostic factors for response to chemoradiotherapy and locoregional tumor control (p < 0.01). Pathologic response to neoadjuvant therapy was also predictive of locoregional control (p < 0.001). Patients with a pretreatment Hgb > or = 14.5 g/dL had significantly higher complete response, locoregional control, and survival rates than the patients with a pretreatment Hgb < 14.5 g/dL who did not receive r-HuEPO (p < 0.05). The response, control, and survival rates in patients with a pretreatment Hgb < 14.5 g/dL given r-HuEPO were significantly higher than in low Hgb patients not given r-HuEPO (p < or = 0.001) and equivalent to patients with a pretreatment Hgb > 14.5 g/dL (p > or = 0.3). CONCLUSION: Low pretreatment Hgb is a negative prognostic factor for oral cavity and oropharyngeal SCCA patients, but was completely abrogated by r-HuEpo administration during neoadjuvant chemoradiotherapy. Randomized trials of radiation and/or chemotherapy with or without r-HuEPO for patients whose Hgb level is either low at the start of therapy or is anticipated to become low during therapy are indicated.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2001

Brain potentials in human patients with extremely severe diffuse brain damage.

To test higher cortical functions of neurological patients, oddball tasks are often used in which a frequent and a rare stimulus are randomly presented and a P3 brain wave is recorded to the rare stimulus. We examined 33 patients with extremely severe brain injury. Three oddball conditions were used: with two sine tones (ST), with two complex tones (CT) and with vowels 'o' and 'i'. Across all patients, CT elicited P3 more often than ST, and the occurrence of the P3 after vowels was intermediate. However, among patients who showed a distinct P3 wave, its amplitude in the subgroup with traumatic brain injury was larger to vowels than to CT. In patients with non-traumatic etiology, CT and vowels elicited a P3 of a nearly equal amplitude. Stimuli of sufficient complexity should be used when the P3 technique is applied for assessment of cortical functions in severely impaired patients.

Adolescent↗
PubMed2001

c-mpl mutations are the cause of congenital amegakaryocytic thrombocytopenia.

Congenital amegakaryocytic thrombocytopenia (CAMT) is a rare disease presenting with isolated thrombocytopenia in infancy and developing into a pancytopenia in later childhood. Thrombopoietin (TPO) is the main regulator of thrombocytopoiesis and has also been demonstrated to be an important factor in early hematopoiesis. We analyzed 9 patients with CAMT for defects in TPO production and reactivity. We found high levels of TPO in the sera of all patients. However, platelets and hematopoietic progenitor cells of patients with CAMT did not show any reactivity to TPO, as measured by testing TPO-synergism to adenosine diphosphate in platelet activation or by megakaryocyte colony assays. Flow cytometric analysis revealed absent surface expression of the TPO receptor c-Mpl in 3 of 3 patients. Sequence analysis of the c-mpl gene revealed point mutations in 8 of 8 patients: We found frameshift or nonsense mutations that are predicted to result in a complete loss of c-Mpl function in 5 patients. Heterozygous or homozygous missense mutations predicted to lead to amino acid exchanges in the extracellular domain of the receptor were found in 3 other patients. The type of mutations correlated with the clinical course of the disease. We propose a defective c-Mpl expression due to c-mpl mutations as the cause for thrombocytopenia and progression into pancytopenia seen in patients with CAMT.

Adenosine Diphosphate↗
PubMed2001

Adenovirus-based overexpression of tissue inhibitor of metalloproteinases 1 reduces tissue damage in the joints of tumor necrosis factor alpha transgenic mice.

OBJECTIVE: Rheumatoid arthritis is a prototype of a destructive inflammatory disease. Inflammation triggered by the overexpression of tumor necrosis factor alpha (TNFalpha) is a driving force of this disorder and mediates tissue destruction. Since matrix metalloproteinases (MMPs) are among the molecules activated by TNFalpha, we hypothesized that overexpression of their natural inhibitor, tissue inhibitor of metalloproteinases 1 (TIMP-1), in TNFalpha transgenic mice could inhibit the development of destructive arthritis. METHODS: Systemic treatment was carried out by replication-defective adenoviral vectors for TIMP-1, beta-galactosidase, or phosphate buffered saline (PBS), which were applied once at the onset of arthritis. Clinical, serologic, radiologic, and histologic outcomes were assessed 18 days after the treatment. RESULTS: The AdTIMP-1 group showed significantly reduced paw swelling and increased grip strength compared with the 2 control groups, whereas total body weight, TNFalpha, and interleukin-6 levels were similar in all 3 groups. Radiographic assessment revealed a significant reduction of joint destruction in the AdTIMP-1 group; this was confirmed by histologic analyses showing reduced formation of pannus and erosions in the AdTIMP-1 group compared with the AdLacZ and PBS control groups. The formation of arthritis-specific autoantibodies to heterogeneous nuclear RNP A2 was not observed in the AdTIMP-1 group but was present in the 2 control groups. CONCLUSION: These results indicate a central role of MMPs in TNFalpha-mediated tissue damage in vivo and a promising therapeutic role for TIMP-1.

Adenoviridae↗
PubMed2001

Effects of 50 Hz magnetic field on cell cycle kinetics and the colony forming ability of budding yeast exposed to ultraviolet radiation.

To investigate the effects of extremely low frequency magnetic fields on ultraviolet radiation (UV) exposed budding yeast, haploid yeast (Saccharomyces cerevisiae) cells of the strain SEy2101a were exposed to 50 Hz sine wave magnetic field (MF) of 120 microT with simultaneous exposure to UV radiation. Most of the UV energy was in the UVB range (280-320 nm). The biologically weighted (CIE action spectrum) dose level for the UV radiation was 175 J/m2. We examined whether 50 Hz MF affected the ability of UV irradiated yeast cells to form colonies (Colony Forming Units, CFUs). In addition, the effect of coexposure on cell cycle kinetics was investigated. Although the significant effect of MF on the cell cycle phases of UV exposed yeast cells was seen only at one time point, the overall results showed that MF exposure may influence the cell cycle kinetics at the first cycle after UV irradiation. The effect of our particular MF exposure on the colony forming ability of the UV irradiated yeast cells was statistically significant 420 min after UV irradiation. Moreover, at 240, 360, and 420 min after UV irradiation, there were fewer CFUs in every experiment in (UV+MF) exposed populations than in only UV exposed yeast populations. These results could indicate that MF exposure in conjunction with UV may have some effects on yeast cell survival or growth.

Cell Cycle↗
PubMed2001

[Differential diagnostic problems in assessment of benign bone tumors].

The diagnosis of benign bone tumors can cause many problems and a definitive histological diagnosis is often impossible without the knowledge of clinical datas, age of the patient and anatomical location of the tumor. Therefor cooperation between pathologist, orthopedic surgeon and radiologist is necessary, to reduce the risk of misinterpretation of benign and malignant bone tumors. Benign bone tumors often show a heterogenous histology and overlapping morphology between different entities has to be kept in mind, as well as the sampling error in biopsy- and frozen section material. In most cases the pathologist has to rely on conventional stainings because the immunohistochemistry stainings are often not helpful.

Adolescent↗
PubMed2001

[Diagnostic imaging of giant cell tumors].

Although classified as benign neoplasms, giant cell tumors are locally aggressive with a high recurrence rate of 30-50%. The histological appearance include osteoclast-like, multinucleated giant cells and round to spindle-shaped mono-nuclear stromal cells. These neoplasms predominately affect adults in the third and forth decades of life (70-80%). Giant cell tumors predominately arise in long tubular bones (75-95%) with the majority occurring around the knee (50%). The next most common site being the distal radius (10%). The epicenter of giant cell tumors is in the epiphysis. The radiographic signs of giant cell tumors are a geographical radiolucency with no internal mineralization, a thinning of the cortex, eccentric in the epiphysis of long bones. MRI signs of giant cell tumors are high signal intensity in T2-weighted images, high contrast media enhancement, fluid levels, signs according to haemorrhage and haemosiderin deposition. CT shows the expanded and thinned cortex. Plain radiographs remain the mainstay of diagnosis of giant cell tumors. MRI and CT are important for staging and therefore for surgical planning.

Bone Neoplasms↗
PubMed2001

Skeletal cystic angiomatosis with severe hip joint deformation resembling massive osteolysis.

An aggressive destruction pattern resulting in joint deformation has not been described in skeletal cystic angiomatosis (SCA) so far. We present the case of a 6-year-old boy with such findings strongly resembling Gorham's disease (massive osteolysis). Since the prognosis of the latter entity tends to be less favorable than in SCA, particularly SCA without extraskeletal involvement, careful differentiation of both disorders appears to be important.

Angiomatosis↗
PubMed2001

Sequential chemo- and radiochemotherapy with weekly paclitaxel (Taxol) and 3D-conformal radiotherapy of stage III inoperable non-small cell lung cancer. Results of a dose escalation study.

The purpose of this study was the determination of the maximum tolerable dose (MTD) of weekly paclitaxel (PX) in combination with 3D-conformal radiotherapy in non-small cell lung cancer (NSCLC) and the evaluation of side effects, patient outcome and tumor response. Thirty-eight patients with inoperable NSCLC, UICC-stage IIIA (n=14)/IIIB (n=24) received two cycles of induction chemotherapy with PX/carboplatin followed by combined radiochemotherapy (60 Gy/6 weeks) with weekly PX which was escalated in cohorts of four patients until dose limiting toxicity (DLT) was reached. Starting level was 40 mg/m(2). 3D-conformal radiotherapy was applied in all patients. Toxicity was determined by WHO criteria. Patients were followed-up 3-monthly. Thirty eight patients have entered the study, 34 patients are evaluable. DLT was esophagitis III degrees, requiring interruption of radiotherapy and was reached at the PX 70 mg/m(2). Two hypersensitivity reactions (50 mg/m(2)) and one leucopenia III degrees (60 mg/m(2)) were observed. Only one patient (60 mg/m(2), 50 Gy) completely aborted treatment. The pneumonitis rate was between 21 and 36% but showed no clear correlation with PX dose. Tumor response (PR and CR) defined by CT-scan 6 weeks following radiotherapy was 88% (30/34). The 1- and 2-year survival rate is 73% and 34%. We conclude that the MTD of weekly PX with 60 Gy normofractionated radiotherapy is 60 mg/m(2). The DLT is esophagitis. Response and survival data of this sequential/combined approach are promising. A minor increase of pulmonary toxicity of irradiation is suspected.

Antineoplastic Combined Chemotherapy Protocols↗