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Biomedical subjects

J A Werner

Publications and source records attributed to J A Werner.

At least 37 records · Page 2Linked to original sources
PubMed2005

[Analysis of cost effectiveness of photodynamic therapy with Foscan (Foscan-PDT) in comparison with palliative chemotherapy in patients with advanced head-neck tumors in Germany].

BACKGROUND: The purpose of this manuscript is to give a cost-effectiveness analysis of the photodynamic therapy by means of Foscan (Foscan-PDT) in Germany. The basis for this paper is provided by a study performed in Great Britain which analyses the costs of Foscan-PDT compared to the costs of palliative chemotherapy and to the option of no treatment in patients with advanced head and neck cancer. METHOD: In order to calculate the cost-effectiveness, an already published model developed on the base of English data was fed with German cost-data. For consideration of the different characteristics of cost-parameters as well as to minimize the over- or underestimation of the costs, sensitivity analyses were performed. RESULTS: The Foscan-PDT revealed the highest health-related effectiveness compared to all other above-mentioned options -- 129 additional days of life in comparison to no treatment or 48 days in comparison to four cycles of palliative chemotherapy. The costs per therapy of Foscan-PDT ( 8,761 euros) were lower than those of four cycles of palliative chemotherapy (11,600 euros). CONCLUSION: Foscan-PDT is a cost-effective treatment option for patients suffering from advanced head and neck cancer. For patients who up to now had only very limited treatment possibilities at their disposition, Foscan-PDT offers a chance for reduction of the tumor, remission, and a prolonged expectancy of life.

Ambulatory Care↗
PubMed2005

Lymphocyte subsets in irradiation-induced sialadenitis of the submandibular gland.

AIMS: Irradiation-induced sialadenitis is a significant cause of morbidity in head and neck cancer patients receiving radiotherapy. Neither the exact aetiopathology of chronic irradiation-induced sialadenitis nor the mechanisms leading to atrophy of the glandular cells associated with an increase in extracellular matrix are understood. The aim of our study was to determine the phenotype of the inflammatory infiltrate and to study its distribution in the affected submandibular glands. METHODS AND RESULTS: Paraffin-embedded submandibular glands from a homogeneous group of 19 patients with advanced oropharyngeal cancer who received conventional radiotherapy to the primary site and upper neck were analysed. In all patients the radiation dose and field were approximately equal. The submandibular glands were obtained during neck dissection. To characterize the lymphoid infiltrate, all tissue sections were immunostained for T cells (CD3, CD4, CD8), cytotoxic T cells (granzyme B), B cells (CD20), and macrophages (Ki-M1p). A histopathological classification into four grades was established based on the degree of glandular atrophy, fibrosis and lymphocytic infiltration. Phenotypic analysis of submandibular gland sections revealed that the great majority of lymphocytic infiltrates were cytotoxic T cells associated with acinar cell destruction. CONCLUSIONS: The significantly elevated frequencies of cytotoxic cells in the submandibular glands of patients with irradiation-induced sialadenitis suggest that cell-mediated immune mechanisms may play a part in the pathogenesis of this disease.

Adult↗
PubMed2005

Characterization of feline immunoglobulin heavy chain variable region genes for the molecular diagnosis of B-cell neoplasia.

To develop a molecular-based assay so that the diagnosis of feline B-cell neoplasia can be facilitated, we have characterized 24 feline immunoglobulin heavy chain variable region (IGH V) complementary DNA (cDNA) transcripts. Structural homology with rearranged human IGH V genes was found, and the sequence information was used to design a feline-specific polymerase chain reaction (PCR)-based assay to amplify the complementarity determining region 3 as a marker for B-cell clonality. Conserved primers derived from the second and third framework regions of V gene segments were used in conjunction with 2 sequence-specific primers and 1 degenerate primer derived from the J gene segments. Each PCR reaction was run in duplicate, and both native and denatured PCR products were evaluated using polyacrylamide gel electrophoresis. Formalin-fixed, paraffin-embedded (FFPE) tissue sections from cats with confirmed B-cell neoplasia (diffuse large B-cell lymphoma, plasmacytoma, and myeloma) were examined, and 15/22 (68.2%) cats produced results indicative of the presence of a monoclonal population of B cells. The evaluation of denatured PCR products (heteroduplex analysis) facilitated a more accurate interpretation in 3/15 (20%) cats. Pseudoclonality was a major reason for the failure to detect monoclonality. Poor DNA quality is a significant concern and was responsible for the removal of 2 cats from the study. Using this assay, FFPE normal feline lymphoid tissues and unfixed peripheral blood mononuclear cells were determined to be composed of polyclonal populations of B cells. This assay represents a useful adjunctive diagnostic tool for the diagnosis and investigation of feline B-cell lymphoproliferative disorders.

Amino Acid Sequence↗
PubMed2004

Photodynamic effects of anthracyclin derivatives on squamous cell carcinoma cell lines of the head and neck.

BACKGROUND AND OBJECTIVE: In the last years, photodynamic therapy, performed with hematoporphyrin derivatives, gained in importance for the treatment of superficially situated malignomas. The use of hematoporphyrin as photosensitizer is limited especially by the low depth of penetration and its side effects. The aim of the present study was to evaluate the effectiveness of photodynamic therapy with anthracyclin derivates in squamous cell carcinoma cell lines. STUDY DESIGN/MATERIALS AND METHODS: The photodynamic effects of the anthracyclin derivates adriamycin and epirubicin as well as the effects of the hematoporphyrin derivatives photofrin-II and photosan-3 were examined and compared in 10 squamous cell carcinoma cell lines derived from head and neck tumors. RESULTS: Beside their cytostatic effect, the applied cytostatics revealed a marked photodynamic effect. A statistically significant difference for photodynamic effects of both cytostatic agents and the hematoporphyrin derivates could not be shown. CONCLUSIONS: These results revealed that the above mentioned cytostatics could be considered as possible alternative photosensitizer for photodynamic therapy.

Antineoplastic Agents↗
PubMed2004

[Embolization of pulmonary arteriovenous malformations with electrolytically detachable coils in patients with hereditary hemorrhagic telangiectasia].

BACKGROUND: Pulmonary arteriovenous malformations (PAVM) can be found in approximately 20 % to 35 % of patients with hereditary hemorrhagic telangiectasia (HHT). PAVM should be treated since they are a source of paradoxical embolization, potentially resulting in severe neurologic complications. The treatment of choice is the endovascular embolization with coils. PATIENTS AND METHODS: Seven patients with HHT underwent superselective embolization of PAVM detected during screening for PAVM. Four patients had a single PAVM and one patient 3, 4 and 5 PAVMs, respectively. Electrolytically detachable coils were used for embolization. In addition, coils with synthetic fibers were used during 6 embolizations for completion of embolization. RESULTS: Embolization was technically successful in all patients. Complete primary occlusion was achieved in all PAVM. No coil migration or occlusion of unaffected pulmonary arteries was observed. After embolization, one patient developed a small pleural effusion, which was treated symptomatically. CONCLUSION: As a minimally invasive procedure, superselective embolization is the treatment of choice in treating PAVM in patients with HHT. With the use of electrolytically detachable coils, the ideal coil size can be chosen and exact placement achieved without the risk of coil migration or occlusion of unaffected pulmonary arteries.

Adolescent↗
PubMed2004

Lipoic acid is 10 times more toxic in cats than reported in humans, dogs or rats.

The antioxidant lipoic acid (LA) is administered to humans and pets. We described acute toxicity and maximum tolerated dose (MTD) of LA in cats. In progression, 10 healthy adult male cats received orally 60 (high), 30 (low), or 0 mg LA/kg (control). Serum enzyme activities and concentrations of bile acids, ammonia, amino acids (AA), LA and dihydrolipoic acid (DHLA) were measured, and tissues examined microscopically. Significant clinical toxicity with changes in ammonia and AA concentrations occurred in all high-dose cats. Oral LA produced hepatocellular toxicity and MTD was < 30 mg/kg in cats.

Administration, Oral↗
PubMed2004

Is there a role for chemosensitivity tests in head and neck cancer?

Despite many advances in predictive testing of human malignancies, we are far from using it routinely in clinical practice. Investigating the responsiveness of solid tumors to cytostatic drugs is particularly challenging. Nevertheless, for head and neck cancer, chemosensitivity testing is an increasingly attractive option, since chemotherapy has proven to have curative potential in the therapy of head and neck cancer, in particular in combination with radiation. The significant need for predictive methods to identify patients responsive to therapy, first of all in organ preservation programs, which is an alternative to first-line surgery, had recently renewed the discussion on a possible role of chemosensitivity testing in head and neck cancer. In this review, we discuss the current state of chemosensitivity testing in head and neck cancer. Recent methodological developments, in particular elimination of photochemical artifacts and inclusion of stromal cell response studies, may soon augment the value of ex vivo chemosensitivity testing for the management of head and neck cancer.

Antineoplastic Agents↗
PubMed2004

Management of N0 neck in head and neck cancer: current controversies.

Squamous cell carcinomas of the upper aerodigestive tract are characterized by a high frequency of lymphogenic metastatic spread. The neck should be included in the treatment concept because almost 25% of all patients develop occult lymph node metastases. The only exception are early carcinomas of the lower lip and the vocal cords. Since currently for high risk patients no prognostic markers or other factors for occult metastatic spread are available, treatment strategies have to include the exact knowledge of direction and extent of regional lymphatic drainage. Based on this prerequisite, concepts for selective cervical lymph node dissection in case of the clinical N0 situation were developed which may also be used for an individually optimized radiotherapy. Intensity modulated radiotherapy (IMRT) bears a high potential for an optimized irradiation in case of potential occult metastatic spread of carcinomas of the upper aerodigestive tract. Without compromising local control rates IMRT allows a considerable reduction of permanent xerostomia by sparing at least one major salivary gland. The significant scientific purpose for the N0 neck, however, will remain the identification of high-risk patients, e.g. by means of tissue and/or serum-related markers, which carry a high risk of local and distant metastases.

Carcinoma, Squamous Cell↗
PubMed2004

Selective high-dose intra-arterial cisplatin as palliative treatment for incurable head and neck cancer.

OBJECTIVE: The purpose of the present study was to evaluate the palliative effect of selective intra-arterial chemotherapy in progressive unresectable head and neck cancer previously treated with radiochemotherapy. PATIENTS AND METHODS: 8 patients with advanced residual or recurrent squamous cell carcinoma of the head and neck were evaluated. These patients were included in the present study particularly because of progredient pain and recurrent bleedings due to tumor progression. In addition 6/8 patients suffered from unpleasant tumor-related smell. All patients received simultaneous infusions of cisplatin (150 mg/m2) intra-arterially to the tumor and sodium thiosulfate intravenously (9 g/m2) for systemic neutralization of cisplatin. The patients were treated by at most 4 cycles of selective intra-arterial chemotherapy via femoral approach. RESULTS: Tumor-associated pain, occurrence of tumor bleeding and tumor-related smell were reduced after at least 2 cycles of intra-arterial chemotherapy in all patients. Clinical and radiological assessment of the primary tumor site revealed a partial response in 4 patients while 4 patients were classified as nonresponders. Intra-arterial cisplatin treatment was well tolerated. CONCLUSION: Selective intra-arterial cisplatin therapy can be delivered safely for palliation of tumor-related symptoms of incurable head and neck cancer.

Antineoplastic Agents↗
PubMed2004

Bilateral congenital dacryocystocele as a cause of respiratory distress in a newborn.

Newborns with respiratory distress and nasal obstruction must be examined for congenital dacryocystocele. This disease is caused by a stenosis in the proximal and distal area of the nasolacrimal duct and leads to a cystic dilatation of this duct. A case of a newborn with bilateral dacryocystocele and dyspnoea is presented. The otorhinolaryngologic as well as the paediatric examination could only reveal in the rhinoscopic examination a tumor of the left nasal cavity that partly obstructed the endonasal space. No other pathologic findings were detected. To clarify the origin and the localization of the tumor as well as to exclude an intracranial relation, a magnetic resonance imaging of the middle face and the frontal skull base was performed. After probe and rinsing of the lacrimal ducts the symptoms improved rapidly. In newborns with nasal obstruction a bilateral rhinoscopy of the lower nasal meatus is required to exclude the existence of a dacryocystocele.

Humans↗
PubMed2004

Significant correlation of matrix metalloproteinase and macrophage colony-stimulating factor serum concentrations in patients with head and neck cancer.

Serum matrix metalloproteinases (MMPs) and the macrophage colony-stimulating factor (M-CSF) are of potential interest as serum tumor markers in various malignancies. There is still a lack of reliable tumor markers in patients with squamous cell carcinoma of the head and neck (SCCHN). Therefore, the tumor marker potential of MMPs and M-CSF was investigated in these malignancies. Serum of 59 patients suffering from SCCHN and of 59 healthy volunteers was obtained. The concentration of MMP-3, MMP-8, MMP-9, and M-CSF was determined by sandwich enzyme immunoassays. The MMP- 3, -8, -9, as well as the M-CSF serum concentrations were significantly elevated in the patient group, compared to the healthy controls (p<0.001, p<0.05, p<0.001, p=0.002). There was significant correlation between the M-CSF and the MMP-3 serum concentration (p<0.0001), and between the M-CSF and the MMP-8 serum concentration (p=0.005). A significant correlation with the tumor stage was found only for MMP-8. MMP and M-CSF serum concentrations are of potential interest as serum tumor markers in SCCHN.

Adult↗
PubMed2003

Extent of surgical intervention in case of N0 neck in head and neck cancer patients: an analysis of data collection of 39 hospitals.

In the discussion on the treatment of the clinical N0 neck in head and neck cancer, the sentinel lymphonodectomy is gaining more and more in significance. Prior to a multicentre study on the value of sentinel lymphonodectomy, it seemed to be desirable to collect data on the current practice of neck dissection in German ENT departments. First a standardised questionnaire was sent to 50 hospitals in Germany. It contained questions on the respective therapeutic concepts (uni- or bilateral modified radical neck dissection versus selective neck dissection, wait-and-see policy) in histologically proven squamous cell carcinoma (G2) and defined localisation of the primary tumour (T1-T2 carcinoma of the oral cavity, the oropharynx and hypopharynx as well as larynx). Summing up the evaluation of 39 anonymously answered questionnaires, it can be stated that no uniform therapeutic concept for the treatment of the cervical lymph nodes in carcinomas of the upper aerodigestive tract based on the stage of lymphatic metastatic disease exists. It seems to be essential to elaborate such a concept in order to be able to compete in the international context. Likewise, a widespread uniform therapeutic strategy would be the basic prerequisite for the initiation and realisation of multicentric therapy studies.

Aged↗
PubMed2003

Wound healing after laser treatment of oral and oropharyngeal cancer.

The wound healing after laser surgery is delayed in contrast to conventional scalpel surgery. There are some animal studies, which investigated the effects of laser surgery upon wound healing, whereas clinical investigations on wound healing of human mucous membrane after laser surgery is missing. A histological study on the laryngeal mucosa of 11 patients after laser incisions who underwent emergent laser debulking surgery for acute airway obstruction and a clinical study of 24 patients with oral or oropharynx cancer who were treated by laser surgery were performed to investigate the course of wound healing. The histological findings showed that the beginning of wound healing was delayed after laser surgery. The duration of wound healing after laser surgical tumour resection revealed a clear dependence on the size of the initial defect. The average duration of wound healing after CO(2) laser surgery (32.8 +/- 9.2 days) was significantly shorter than after Nd:YAG laser surgery (40.4 +/- 9.2). Due to the more pronounced zone of necrosis at the base of the wound ground this effect is more evident using the Nd:YAG laser. However, the different course of wound healing with both laser systems does not seem to have a negative influence on functional results.

Adult↗
PubMed2003

Coagulation and temperature distribution in Nd: YAG interstitial laser thermotherapy: an in vitro animal study.

Interstitial laser thermotherapy (ILTT) was performed increasingly for local destruction of different tumours. The proposal of the present study was the optimisation of the therapy-relevant ILTT parameters and laser application forms which are a prerequisite for the development of an optimal tumour treatment strategy. Laser-induced temperature changes and coagulation patterns with different laser light applicators (bare fibre, ring mode fibre, side fibre, diffuser fibre) were investigated on liver, spleen and tongue tissues of 26 adult pigs after interstitial thermotherapy with Nd: YAG laser. Analysis of experimental results on ILTT and tissue necrosis showed a dependence on laser exposure time, type of laser fibre and applied laser energy. The most homogeneous and extensive coagulation zone was seen after laser treatment with rather low energy over a longer time period.

Animals↗
PubMed2003

Sialolith crystals localized intraglandularly and in the Wharton's duct of the human submandibular gland: an X-ray diffraction analysis.

The exact cause of the formation of sialoliths is unknown. Detailed knowledge of pathogenesis of sialolithiasis and composition of sialoliths is necessary to define new therapeutic procedures. The crystalline components of 23 sialoliths of human submandibular gland were investigated by X-ray powder diffraction analysis. All of the sialoliths localized in the ducts in the submandibular gland consisted of hydroxylapatite. However, in the sialoliths in the Wharton's duct, hydroxylapatite as well as whitlockite and brushite could be found in all except one case. Whitlockite was observed more often in the nucleus of the sialoliths and it was a common co-phase along with hydroxylapatite. The nucleus in one sialolith consisted of brushite and the cortex showed a co-phase of hydroxylapatite and brushite. The occurrence of whitlockite in the sialoliths in Wharton's duct may be due to a higher concentration of calcium and phosphate in saliva in this duct.

Adult↗
PubMed2003

Peritonsillar abscess--critical analysis of abscess tonsillectomy.

The risk of secondary haemorrhage following abscess tonsillectomy is reported in the literature with differing rates. A retro- and prospective analysis of complication rates following abscess tonsillectomy was conducted in 142 patients (54 females, 88 males; mean age: 35 years). In 22% of patients, a secondary haemorrhage occurred. In half of these (11% of total), the haemorrhage had to be treated surgically. Secondary haemorrhage occurred most commonly on the 6th and 8th postoperative days. Reports in the literature are not in unison about the risk of secondary haemorrhage following abscess tonsillectomy and therefore allow no final judgement about an objective risk of this complication. This report strengthens the results of the 'Comparative Audit Service' analysis from 1997, which did show a high risk of secondary haemorrhage following tonsillectomy, as well as following abscess tonsillectomy.

Adolescent↗