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Biomedical subjects

Michael Landthaler

Publications and source records attributed to Michael Landthaler.

At least 73 records · Page 4Linked to original sources
PubMed2003

Spindle cell hemangioma.

BACKGROUND: Spindle cell hemangioma (SCH) is an uncommon benign vascular tumor. OBJECTIVE: To report and discuss a case of SCH in an 11-year-old boy. METHODS: A case report and discussion of the rare entity of SCH are given. RESULTS: The excision of a vascular tumor showed a vascular connection to the great saphenous vein. Histologic examination was consistent with SCH. CONCLUSION: The diagnosis of SCH is supported by typical histologic and immunohistochemical features and by the intraoperative finding of an association with a large vessel.

Child↗
PubMed2003

Dermoscopy of pigmented skin lesions: results of a consensus meeting via the Internet.

BACKGROUND: There is a need for better standardization of the dermoscopic terminology in assessing pigmented skin lesions. OBJECTIVE: The virtual Consensus Net Meeting on Dermoscopy was organized to investigate reproducibility and validity of the various features and diagnostic algorithms. METHODS: Dermoscopic images of 108 lesions were evaluated via the Internet by 40 experienced dermoscopists using a 2-step diagnostic procedure. The first-step algorithm distinguished melanocytic versus nonmelanocytic lesions. The second step in the diagnostic procedure used 4 algorithms (pattern analysis, ABCD rule, Menzies method, and 7-point checklist) to distinguish melanoma versus benign melanocytic lesions. kappa Values, log odds ratios, sensitivity, specificity, and positive likelihood ratios were estimated for all diagnostic algorithms and dermoscopic features. RESULTS: Interobserver agreement was fair to good for all diagnostic methods, but it was poor for the majority of dermoscopic criteria. Intraobserver agreement was good to excellent for all algorithms and features considered. Pattern analysis allowed the best diagnostic performance (positive likelihood ratio: 5.1), whereas alternative algorithms revealed comparable sensitivity but less specificity. Interobserver agreement on management decisions made by dermoscopy was fairly good (mean kappa value: 0.53). CONCLUSION: The virtual Consensus Net Meeting on Dermoscopy represents a valid tool for better standardization of the dermoscopic terminology and, moreover, opens up a new territory for diagnosing and managing pigmented skin lesions.

Algorithms↗
PubMed2003

Branched filaments no fungus, ovoid bodies no bacteria: Two unusual cases of mycetoma.

We describe a 58-year-old man presenting with necrotizing panniculitis of the lower right leg and a 64-year-old woman with a clinically similar lesion combined with pustular eruptions and subsequent ulceration on the forehead. In the first patient, Giemsa staining showed small ovoid bodies and Grocott staining revealed hyphae. Histology from the process on the forehead showed branched filaments in the periodic acid-Schiff (PAS) staining. In the first case, Madurella mycetomatis, a fungus, was the pathogenic agent, whereas in the other case white colonies of filamentous organisms resembling fungi could be cultivated that turned out to be the bacterium Nocardia brasiliensis. Since the initial clinical appearance of these two forms of mycetoma were almost identical and histopathologic findings were inconclusive, only sophisticated microbiologic work-up of material from lesional skin led to the correct diagnosis. In times of global tourism, these unusual cases impressively document the necessity to become more familiar with mycetoma to make accurate therapeutic decisions with effective results, possibly saving a limb.

Antifungal Agents↗
PubMed2003

Variable pulse frequency-doubled Nd:YAG laser versus flashlamp-pumped pulsed dye laser in the treatment of port wine stains.

The flashlamp-pumped pulsed dye laser (FPDL) is regarded as the gold standard in the treatment of port wine stains. The purpose of this prospective, intra-individual, comparative clinical study was to investigate whether a frequency-doubled variable pulsed Nd:YAG laser (frequency-doubled Nd:YAG) is equally as safe and effective as established lasers. Forty-three patients with port wine stains were included in the study. Test treatments were performed using the frequency-doubled Nd:YAG laser (532 nm; 4 mm psi; 5-50 ms; 5.5 to 15 J/cm2) versus the FPDL (585 nm; 450 micros; 7 mm psi; 6 J/cm2). After 6 weeks, a full lesional treatment was performed using the device and the parameters showing the best clearance and the fewest side effects. The clearance of the lesions was generally good to fair. With the exception of poor results at 5 ms and 5.5 J/cm2 with the frequency-doubled Nd:YAG laser, there were no significant differences between the two laser devices. Scar formation, nevertheless, occurred in only 3% of the FPDL-treated sites versus up to 18% of the frequency-doubled Nd:YAG sites, increasing with pulse duration. In port wine stains, the FPDL remains the therapy of choice because of the somewhat better results and a lower frequency of side effects, especially scarring.

Adolescent↗
PubMed2003

Heat shock protein 70 membrane expression and melanoma-associated marker phenotype in primary and metastatic melanoma.

Cell membrane localization of the 72 kDa heat shock protein 70 (Hsp70) has been found on different tumour cell lines, on biopsy material from solid tumours and metastases and on leukaemic blasts from acute myelogenous leukaemia patients, but not on the corresponding normal tissues, as determined by flow cytometry using the Hsp70-specific monoclonal antibody C92F3B1. In the present study Hsp70 membrane expression was studied on primary malignant melanomas, melanoma metastases, melanocytes, human skin fibroblasts and peripheral blood lymphocytes, together with expression of the melanoma-associated markers Mel-1, Mel-2 and Mel-5, major histocompatibility complex class I and the fibroblast-specific marker ASO2. As previously shown, fibroblasts and peripheral blood lymphocytes from healthy human volunteers were found to be negative for Hsp70 and for the melanoma-associated markers Mel-1, Mel-2 and Mel-5. Human melanocytes from healthy human donors were also negative for Hsp70, but were positive for Mel-1 and Mel-5. Independent of the Clark's level, all the malignant melanomas (n = 9) and metastases (n = 11) exhibited were positive for both Mel-1 and Mel-2. The primary melanomas could be divided into two groups according to their Hsp70 and Mel-5 expression pattern: those with an Hsp70-negative and a Mel-5-positive phenotype (-/+) (five out of nine), and those with an Hsp70-positive and a Mel-5-negative phenotype (+/-) (four out of nine). All the melanoma metastases (n = 11) had an Hsp70-positive, Mel-5-negative phenotype (+/-). These data provide the first hint that the marker combination Hsp70 positive/Mel-5 negative might be useful in estimating the metastatic potential of a melanoma. Investigations on changes in the marker combination Hsp70/Mel-5 during onset of melanoma disease and progression will clarify its potential as a prognostic risk factor.

Adult↗
PubMed2003

Discrimination between gene expression patterns in the invasive margin and the tumour core of malignant melanomas.

Genes that determine the invasive capacity of the invasive front of malignant melanomas (MM) have not yet been systematically investigated in vivo. Therefore, we combined laser pressure catapulting (LPC) microdissection with cDNA microarray technology (DermArray, Research Genetics, representing about 5700 genes) to systematically analyse differences in gene expression profiles between the invasive margin and the tumour centre in nine cases of vertical growth phase MM. Signal-to-noise statistical algorithms combined with hierarchical clustering were performed to determine class-separating genes. The gene encoding phosphoenolpyruvate carboxykinase 1 (PEPCK), the Homo sapiens gene similar to Saccharomyces cerevisiae SSM4 (TEB4), the gene encoding ribosomal protein L19, the Homo sapiens gene similar to the Aspergillus nidulans SudD (a suppressor of the bimD6 homologue), the gene encoding the interleukin-3 receptor alpha subunit, the gene encoding the inositol 1,4,5-triphosphate 3-kinase isoenzyme, and three anonymous expressed sequence tags were identified as class-separating genes. These genes significantly discriminate between the invasive front and the tumour centre. Using this set of genes, 15 out of 18 LPC-dissected MM regions could be grouped correctly. We conclude that the candidate genes identified could spark further research on MM progression and may provide novel prognostic parameters.

Algorithms↗
PubMed2003

Treatment of Old World cutaneous leishmaniasis with intralesionally injected meglumine antimoniate using a Dermojet device.

Pentavalent antimonial compounds, the mainstay in the treatment of the various forms of leishmaniasis, have considerable toxicity, are difficult to administer and expensive. We describe a safe and efficient therapeutic modality using a spring-loaded and air-powered device for the intralesional injection of a high-velocity meglumine antimoniate microspray in a patient with cutaneous leishmaniasis.

Adolescent↗
PubMed2003

Orofacial granulomatosis as the initial presentation of Crohn's disease in an adolescent.

Orofacial granulomatosis (OFG) is a rare and heterogeneous clinical condition that presents with chronic swelling of the oral or facial tissues due to granulomatous inflammation. It is histologically characterized by noncaseating giant cell granulomata and epithelioid histiocytes. OFG includes the previously recognized clinical entities of Melkersson-Rosenthal syndrome and cheilitis granulomatosa (Miescher's cheilitis). A consistently effective medical treatment is not currently available. We describe an adolescent patient with a history of recurrent orofacial swelling preceding gastrointestinal symptoms by several years. He exhibited clinical and histological changes consistent with the diagnosis of OFG. It was resistant to standard therapies such as topical corticosteroids. Thorough history taking and clinical examination suggested Crohn's disease (CD), and further tests confirmed the diagnosis. The patient improved promptly after initiating oral treatment for CD with mesalazine and prednisolone. We conclude that OFG may be under- or misdiagnosed since the clinical manifestation may be misleading and its course is independent of or even preceding CD. Thus, patients with OFG should be asked about gastrointestinal symptoms consistent with CD. Those with suspicious symptoms should undergo a careful gastrointestinal evaluation, possibly including enteroclysis and complete gastrointestinal endoscopic examination, especially when the patient's history is conspicuous.

Adolescent↗
PubMed2003

Treatment of atopic dermatitis and impact on quality of life: a review with emphasis on topical non-corticosteroids.

Atopic dermatitis (AD) is a chronic skin disease with increasing prevalence and rising costs. Stigmatisation and pruritus are only some aspects of potential quality-of-life (QOL) impairments. AD is not curable and repeated treatments are often necessary. At present, treatment with topically-applied corticosteroids is state-of-the-art for mild to moderate flare-ups. However, many patients are worried about the use of corticosteroids due to the widespread fear of adverse effects. In this review the present literature is analysed concerning impact on quality of life for topically-applicable alternatives to the state-of-the-art treatment. For comparison reasons, data from other treatment modalities are additionally given. Characteristics of studies were analysed using 'general' (year and mode of publication, type and aim of study, number of patients, and clinical measurement) and 'QOL specific' criteria (type and number of QOL measurements including relevance for study aim and age group, validation in used language, sensitivity to change, and improvement at end of study). QOL data are published only in the minority of studies evaluating treatment efficacy and do not cover the variety of possible therapies. Data are available for tacrolimus, pimecrolimus, UVA/UVB combination and UVB narrowband (topical non-corticosteroidal treatments), as well as for topical corticosteroids, cyclosporin, and inpatient treatment. All studies provided a marked improvement in quality of life after therapy. One study assessed quality of life after a treatment-free follow-up period obtaining a clear increase in impact on quality of life. Since studies used different QOL measurements and vary in inclusion criteria, treatment schedules and presentation of results, a comparison of QOL improvement is not recommended. A single randomised study compared topically applied non-corticosteroidal treatment (UVA/UVB combination) with another treatment modality (cyclosporin) and found no difference in QOL improvement. At present, there is a clear lack of controlled randomised studies evaluating different active treatment modalities and their impact on quality of life. Consensus meetings are desirable to formulate guidelines for the selection and correct use of QOL measurements. Patients' fear of side effects (e.g. concerning corticosteroids) should be integrated in QOL questionnaires for evaluation of possible compliance problems and real costs. Since relapse after treatment is frequent in AD, QOL measurements should also be performed after a treatment-free follow-up period. At present, we can not answer the question 'which treatment best improves quality of life in AD?'.

Administration, Topical↗
PubMed2003

Molecular genetic analysis excludes implantation metastasis of basal cell carcinomas.

Basal cell carcinoma (BCC) of the skin is the most common tumor in the white population. A 66-year-old man developed 2 BCCs at the left parietal region of the head and at the helix of the left ear. The 2 lesions matched exactly when pressing the ear against the head, suggesting an implantation metastasis mechanism. Molecular genetic techniques were used to confirm or exclude such a mechanism in this rare clinical constellation. Tumor tissues were precisely microdissected for DNA isolation. Exons 5-9 of the p53 tumor suppressor gene were directly sequenced. In addition, loss of heterozygosity analysis of chromosome 9q was performed using 5 polymorphic microsatellite markers. The BCC of the ear revealed a p53 mutation at codon 273, whereas the other one lacked this mutation. In addition, the smaller BCC of the ear showed loss of heterozygosity at 9q33.3, in contrast with the larger BCC. Interestingly, histologically normal skin of the ear distant from the small BCC had the same deletion, indicating a field defect of this skin patch at 9q33.3. Molecular genetic analysis clearly demonstrated different genetic alterations of the two BCCs and therefore most likely excludes a mechanism of implantation metastasis.

Aged↗
PubMed2003

Loss of EphB6 expression in metastatic melanoma.

Overexpression of various members of the Eph receptor tyrosine kinases and their ephrin ligands has been frequently reported in cancer. In contrast, a loss of EphB6 gene expression has been correlated with a poor prognosis in human neuroblastoma, suggesting a distinct role for this receptor compared to other family members. More recently, an important role of EphB6 signalling in T-cells has been described, suggesting possibly deleterious immunologic effects of a loss of EphB6 in cancer progression. We investigated the expression of EphB6 in melanocytic tumors. EphB6 mRNA of 22 microdissected tissues (7 benign nevi, 7 melanomas, 8 metastases) and 10 different cell lines (normal melanocytes, non-metastatic/metastatic melanoma cell lines) were measured by quantitative real-time RT-PCR. For visualization of EphB6 protein expression, immunohistochemistry of 32 melanocytic lesions were performed. On the mRNA level, the benign nevi revealed the highest EphB6 expression (mean = 1.43), while melanomas (mean = 0.63) and metastases (mean = 0.08; p=0.001) displayed a progressive and significant reduction of EphB6 expression. Accordingly, established melanoma cell lines with metastatic potential showed low EphB6 expression in comparison to normal melanocytes and to most of the melanoma cell lines. Immunohistochemistry revealed homogeneous staining in common nevi, whereas in malignant melanomas and metastases a heterogeneously positive to completely negative EphB6 staining was observed. Remarkably, Spitz nevi stained similarly to ordinary melanocytic nevi. Taken together, we show that melanoma progression to metastatic disease is associated with a significant reduction of EphB6 gene expression which may have considerable consequences for the prognosis of malignant melanoma patients and possible gene-therapeutic approaches.

Adolescent↗
PubMed2002

Hair removal with the long pulsed Nd:YAG laser: a prospective study with one year follow-up.

BACKGROUND AND OBJECTIVE: The aim was to investigate the efficacy, side effects, and the long-term results of a long pulsed Nd:YAG-Laser for hair removal in different hair colors and skin types. STUDY DESIGN/MATERIALS AND METHODS: We performed a prospective clinical study with 29 volunteers. Treatment was performed on the lower leg with a long pulsed Nd:YAG-Laser. Five test areas were treated 1-5 times in monthly intervals; one served as control. Follow-up investigations were performed at each session, and 3, 6, and 12 months after the last therapy. No depilatory treatment except shaving was allowed during the time of follow-up. Percentual hair loss, short- and long-term side effects, and pain during the treatment were evaluated. RESULTS: After one month, a hair loss of greater than 50% was found in 44.9% of the areas treated once. With up to five treatments, this percentage increased up to 71.5%. One year after therapy, a greater than 50% hair reduction was still present in 40% of the five-treatment-areas and in 0% of the areas treated only once. There were no permanent side effects despite one small scar after a folliculitis. CONCLUSIONS: The long pulsed Nd:YAG is suitable to remove hair for more than 12 months effectively, although 4-5 sessions are necessary for these results. Blond hair can also be removed, although much less effective. No lasting side effects could be seen. Darker skin types or tanned skin can also be treated without side effects. A cooling may be advisable due to the pain reported by the volunteers.

Adult↗
PubMed2002

Evaluation of the long pulsed high fluence alexandrite laser therapy of leg telangiectasia.

BACKGROUND AND OBJECTIVES: The treatment of larger leg veins with laser or intense pulsed light often shows varying degrees of success and inconsistent clinical response rates. Aim of this study was to evaluate the effectiveness and safety of the 755 nm long pulsed high fluence alexandrite laser in the treatment of larger leg veins. STUDY DESIGN/MATERIALS AND METHODS: Twenty female volunteers aged 25-51 years (mean 39) with 0.3-1.3 mm leg telangiectasias received laser treatment, 10 of them with an additional pass done right after the first pass. Their skin type ranged from 1 to 3 (five type 1, seven type 2, eight type 3). After test spots with increasing fluences (40-90 J/cm(2)) to determine the individual safe fluence, the maximum fluence of 90 J/cm(2) could be used in all 20 subjects. The spot size was 3 x 10 mm, a spray cooling system was used with 80 milliseconds spray and delay time, respectively. The number of pulses administered ranged from 30 to 467 per subject (mean 139). The treated area was controlled 1 day, 1 month, and 3 months post-treatment and the side effects were quantified. At each visit, the treatment area was photographed. The percent clearance in the treated areas was scored by two observers. Subject satisfaction was evaluated at the 3 months post-treatment visit. RESULTS: After 3 months, in all 20 test subjects some clearance was visible. It ranged from low-grade to complete clearance. Most subjects (15 of 20) had a clearance between 26 and 75%. Hyperpigmentation was observed in 15 subjects. Hypopigmentation was seen in two subjects. No edema, no purpura, no erythema, no scarring, no blistering, and no crusts were observed. Mean subject satisfaction score was assessed and all volunteers reported to be "satisfied." CONCLUSIONS: The long pulsed high fluence alexandrite laser is effective and safe in the treatment of leg veins 0.3-1.3 mm in diameter.

Adult↗