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Dive into the research topics where Helmut Kerl is active.

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Featured researches published by Helmut Kerl.


Journal of Cutaneous Pathology | 1997

Infection by Borrelia burgdorferi and cutaneous B-cell lymphoma.

Lorenzo Cerroni; Natalie Zöchling; Barbara Pütz; Helmut Kerl

In past years, association of primary cutaneous B‐cell lymphoma (CBCL) with infection by Borrelia burgdorferi has been reported in a few patients. The evidence for a pathogenetic role was based on clinical grounds or raised titre of antibodies in serum. Both methods, however, do not prove the association between the micro‐organism and the CBCL, especially in countries where infection by Borrelia burgdorferi is endemic. Moreover, the exact percentage of Borrelia burgdorferi‐positive CBCL is not known. We retrieved from our files 50 cases of CBCL to perform PCR analysis of Borrelia burgdorferi DNA on paraffin‐embedded tissue sections. Only patients with primary CBCL were selected. In all cases, monoclonality of the infiltrate was confirmed by immunohistological pattern of immunoglobulin light chains or molecular analysis of Jh gene rearrangement, or both. Specific DNA sequences of Borrelia burgdorferi‐were identified in cutaneous lesions from 9 patients (follicle center lymphoma: 3/20; immunocytoma: 3/4; marginal zone B‐cell lymphoma: 2/20; diffuse large B‐cell lymphoma: 1/6). Specificity was confirmed by Southern blot hybridisation in all positive cases. We could show that Borrelia burgdorferi, DNA is present in skin lesions from a small proportion of patients (18%) with various types of CBCL. Our results may have therapeutic implications. In analogy to Helicobacter pylori‐associated MALT‐lymphomas, which in some cases can be cured by eradication of Helicobacter pylori infection, a proportion of CBCL may be cured with antibiotic therapy against Borrelia burgdorferi. Although yet speculative, adequate antibiotic treatment for patients with primary CBCL should be considered before more aggressive therapeutic options are applied, particularly in countries where infection by Borrelia burgdorferi is endemic. PCR analysis of Borrelia burgdorferi DNA is a fast test that should be performed in all patients with CBCL to identify those who more likely could benefit from an early antibiotic treatment.


Journal of The American Academy of Dermatology | 1993

Topical photodynamic therapy with endogenous porphyrins after application of 5-aminolevulinic acid: An alternative treatment modality for solar keratoses, superficial squamous cell carcinomas, and basal cell carcinomas?

Peter Wolf; Edgar Rieger; Helmut Kerl

BACKGROUND Topical photodynamic therapy with endogenous porphyrins consists of irradiation of a tumor with visible light after the application of exogenous 5-aminolevulinic acid. OBJECTIVE To assess the effectiveness of this modality, patients with precancerous conditions and various skin cancers were treated. METHODS Thirteen patients with 70 skin lesions were enrolled. Standard treatment involved the topical application of 20% 5-aminolevulinic acid in an oil-in-water emulsion. The emulsion was applied under an occlusive dressing for 4 to 8 hours before exposure to photoactivating light. RESULTS We observed a complete response after a single treatment for all 9 solar keratoses, 5 of 6 early invasive squamous cell carcinomas, and 36 of 37 superficial basal cell carcinomas. Only 1 of 10 nodulo-ulcerative basal cell carcinomas completely resolved. Eight cutaneous metastases of malignant melanoma were therapeutic failures. CONCLUSION Topical photodynamic therapy with endogenous porphyrins is effective for superficial epithelial skin tumors.


Journal of Cutaneous Pathology | 2005

WHO/EORTC classification of cutaneous lymphomas 2005: histological and molecular aspects.

Günter Burg; Werner Kempf; Antonio Cozzio; Josef Feit; Rein Willemze; Elaine S. Jaffe; Reinhard Dummer; Emilio Berti; Lorenzo Cerroni; Sergio Chimenti; José Luis Diaz-Perez; F. Grange; Nancy Lee Harris; Dmitry V. Kazakov; Helmut Kerl; Michael O. Kurrer; Robert Knobler; Chris J. L. M. Meijer; Nicola Pimpinelli; Elisabeth Ralfkiaer; Robin Russell-Jones; Christian A. Sander; Marco Santucci; Wolfram Sterry; Steven H. Swerdlow; Maarten H. Vermeer; Janine Wechsler; Sean Whittaker

Abstract:  The new WHO/EORTC classification for cutaneous lymphomas comprises mature T‐cell and natural killer (NK)‐cell neoplasms, mature B‐cell neoplasms, and immature hematopoietic malignancies. It reflects the unique features of lymphoproliferative diseases of the skin, and at the same time it is as compatible as possible with the concepts underlying the WHO classification for nodal lymphomas and the EORTC classification of cutaneous lymphomas. This article reviews the histological, phenotypical, and molecular genetic features of the various nosological entities included in this new classification. These findings always have to be interpreted in the context of the clinical features and biologic behavior.


The American Journal of Surgical Pathology | 1997

Primary cutaneous marginal zone B-cell lymphoma : A recently described entity of low-grade malignant cutaneous B-cell lymphoma

Lorenzo Cerroni; Sabina Signoretti; Gerald Höfler; Giorgio Annessi; Barbara Pütz; E. Lackinger; Dieter Metze; Alberto Giannetti; Helmut Kerl

Recently a new classification of primary cutaneous B-cell lymphomas (PCBCLs) has been proposed by the European Organization for Research and Treatment of Cancer (EORTC)--Cutaneous Lymphoma Project Group. The marginal zone B-cell lymphomas (MZLs) were not included as a distinct entity because of insufficient experience and controversial opinions. We have studied 32 patients (M:F ratio 1.5:1; age range 25-93 years; mean age 49.6 years; median age 50 years) to determine the diagnostic criteria of primary cutaneous MZL and the relationship with other low-grade malignant PCBCLs. For comparison, three patients with immunocytoma were included in the study. Clinically, patients presented with solitary or clustered reddish or red-brown papules, nodules, and plaques, sometimes surrounded by an erythematous halo. Histopathologic sections showed nodular or diffuse infiltrates involving the dermis and subcutaneous fat. Cytomorphologically small to medium-sized cells with indented nuclei and abundant pale cytoplasm (marginal zone cells, centrocyte-like cells) predominated. In addition, scattered blasts, lymphoplasmacytoid cells, and plasma cells were observed below the epidermis and at the periphery of the infiltrates. Reactive germinal centers were present in 75% of the cases. The three cases of immunocytoma showed a more monomorphous pattern with predominance of lymphoplasmacytoid cells. The marginal zone cells showed a CD20+, CD79a+, CD5- and Bcl-2+ immunophenotype. They expressed immunoglobulin G in the majority of the cases. Staining with the monocytoid B cell-related antibody KiM1p gave positive results in all specimens with a typical intracytoplasmic granular pattern. A monoclonal distribution of immunoglobulin light chains was observed in marginal zone cells in 75% of the cases. Germinal centers, when present, were either polyclonal or negative for both kappa and lambda light chains. Monoclonal rearrangement of the JH gene was detected via polymerase chain reaction (PCR) in 18 of 26 investigated specimens. Analysis in 12 patients of the bcl-2/immunoglobulin heavy chain gene rearrangement using PCR yielded negative results. Lesions were treated by surgical excision followed in some patients by local radiotherapy. Systemic antibiotic therapy was administered to three patients, with good response in two. The prognosis is excellent. After a mean follow-up of 47.9 months (range 6-252; median 24) all patients are alive without signs of systemic lymphoma. Primary cutaneous MZL represents a distinct clinicopathologic subtype of low-grade malignant PCBCL.


American Journal of Dermatopathology | 1989

Surface Microscopy - a New Approach to the Diagnosis of Cutaneous Pigmented Tumors

Hp Soyer; Josef Smolle; S Hodl; H Pachernegg; Helmut Kerl

Clinical guidelines for the diagnosis of pigmented lesions of the skin are not always reliable. Surface microscopy (SM) represents an interesting approach to this problem. For this in vivo investigation, a stereomicroscope, a glass slide, and immersion oil are used. In the present study, the various criteria of SM that cannot be discerned by the naked eye are correlated with the histopathological structures in step-sectioned specimens. Characteristic SM features such as the pigment network, “black dots,” or “irregular extensions” were found to correspond to particular histological findings. SM opens a new dimension of clinical morphology for the diagnosis and differential diagnosis of malignant melanomas, dysplastic nevi, or nonmelanocytic pigmented neoplasms, and facilitates a more reliable preoperative assessment of these lesions.


British Journal of Dermatology | 2007

Epidemiology and aetiology of basal cell carcinoma.

Joachim Roewert-Huber; B. Lange-Asschenfeldt; Eggert Stockfleth; Helmut Kerl

Basal cell carcinoma (BCC) is a malignant epithelial neoplasm of the skin preferentially affecting male caucasians and is rarely observed in patients with more intense skin pigmentation. A characteristic feature of BCCs are their extremely low risk to metastasize. Epidemiological data indicate that the overall incidence is increasing worldwide significantly by about 3–10% per annum. 1–3 Based on the increasing incidence of this usually not life‐threatening tumour BCC appears to develop into a growing public health problem. This review elucidates the risk factors for the development and for the progression of BCC leading to an improved understanding of this tumour.


Journal of The American Academy of Dermatology | 1999

Specific cutaneous infiltrates in patients with myelogenous leukemia: a clinicopathologic study of 26 patients with assessment of diagnostic criteria.

Steven Kaddu; Paul Zenahlik; Christine Beham-Schmid; Helmut Kerl; Lorenzo Cerroni

BACKGROUND Few recent studies have analyzed the clinicopathologic features of specific cutaneous manifestations of myelogenous leukemia in a large number of patients. OBJECTIVE We characterize the clinical and histopathologic spectrum of specific cutaneous manifestations in acute (AML) and chronic (CML) myelogenous leukemia, ascertain further diagnostic criteria, and examine current prognosis. METHODS Thirty-six lesions of specific cutaneous infiltrates from 26 patients with myelogenous leukemia (AML: 17 patients; M:F = 1:2.4; mean age: 52.6 years; AML-French-American-British [FAB] classification subtypes:M1 = 1, M2 = 3, M4 = 8, M5 = 5. CML = 9 patients; M:F = 4.5:1; mean age: 60.6 years) were retrospectively collected for the study. RESULTS Cutaneous manifestations presented as solitary or multiple reddish to violaceous papules, plaques, and nodules (17 lesions), or as a generalized erythematous maculopapular eruption (9 lesions). Concurrent extramedullary involvement in other peripheral sites (eg, gums, pharynx, orbits) was observed in 10 patients. Histopathologically, lesions revealed nodular/diffuse infiltrates, often with perivascular and periadnexal accentuation, sparing of the upper papillary dermis, and prominent single arraying of neoplastic cells between collagen bundles. Extension to the subcutis was noted in all deep biopsy specimens (26 lesions). Cytomorphologically, medium to large-sized mononuclear cells (myeloblasts and atypical myelocytes) predominated in AML-M1 and M2, whereas M4 and M5 mainly showed small, medium-sized, or large mononuclear cells with slightly eosinophilic cytoplasm and indented, bi-lobular, or kidney-shaped nuclei (atypical monocytoid cells). In CML, either a variable mixture of mature and immature cells of the granulocytic series (myelocytes, metamyelocytes, eosinophilic metamyelocytes, and neutrophils) or a rather monomorphous infiltrate of mononuclear cells were found. Staining for naphthol AS-D chloroacetate-esterase (NASD) was positive in 24 of 36 lesions (66.6%; AML: 16; CML: 8). Immunohistochemical analysis on paraffin sections using a large panel of antibodies (16 lesions: AML: 13; CML: 3) showed strong reactivity for LCA (CD45), lysozyme, myeloperoxidase (MPD), LN2 (CD74), HLA-DR, and MT1 (CD43) in the majority of cases, and variable staining for monocyte/macrophage markers (KP1/CD68, PGM1/CD68, Mac387, Ki-M1p). The neuronal cell adhesion molecule (NCAM) marker CD56 was reactive in 2 cases of CML, but negative in all cases of AML. MIB1(Ki67) stained 20% to 80% of neoplastic cells. CD34, CD15, CD20, and CD3 were negative in all cases. No correlation between histochemical/immunohistochemical features with type of leukemia or FAB-subtype of AML was observed. All patients with CML and AML with adequate follow-up died within 24 months after onset of skin lesions (mean survival, AML: 7.6 months; CML: 9.4 months). CONCLUSION Specific cutaneous lesions in AML and CML show distinctive clinicopathologic features that allow diagnosis in most cases. Immunohistochemistry on routinely fixed, paraffin-embedded tissue sections provides useful adjunctive information. Simultaneous expression of lysozyme, MPD, CD45, CD43, and CD74 militates in favor of a diagnosis of specific cutaneous infiltrate of myelogenous leukemia. Pitfalls in immunohistologic diagnosis mainly include lack of expression of some myeloid markers (lysozyme, MPD), and aberrant expression of T-cell markers (eg, CD45RO). Regardless of type of myelogenous leukemia, onset of specific skin manifestations correlates with an aggressive course and short survival.


Journal of Cutaneous Pathology | 2004

Borrelia burgdorferi‐associated lymphocytoma cutis: clinicopathologic, immunophenotypic, and molecular study of 106 cases

Claudia Colli; Bernd Leinweber; Robert R. Müllegger; Andreas Chott; Helmut Kerl; Lorenzo Cerroni

Lymphocytoma cutis (LC) is considered as the stereotypical example of the cutaneous B‐cell pseudolymphomas. It can be induced by various antigenic stimuli including arthropod bites, vaccination, and drugs among others. In endemic regions, Borrelia burgdorferi is the principal causative agent for LC. We studied retrospectively 108 biopsies from 106 patients (male : female, 48 : 58; mean age, 44.6; median, 51.5; range, 3–81) with B. burgdorferi‐associated LC retrieved from the files of the Department of Dermatology of the University of Graz (Austria). Only cases with a B. burgdorferi etiology (typical locations, positivity of serologic and/or polymerase chain reaction (PCR) tests, clinical history) were included in the study. Lesions were located on the nipple (63 cases), earlobe (18 cases), genital region (9 cases), and trunk or extremities (16 cases). PCR analysis of B. burgdorferi DNA was positive in 54 of 80 cases tested (67.5%). In 47 cases, we could retrieve data on serologic examination for B. burgdorferi antibodies performed at the time of diagnosis of LC. Positivity was found in 45 patients (IgG+/IgM+, 5 cases; IgG+/IgM–, 37 cases; IgG–/IgM+, 3 cases; IgG–/IgM–, 2 cases). Histology revealed dense lymphoid infiltrates with prominent germinal centers (GCs) in all cases. Atypical morphologic and/or immunophenotypic features of the GCs were commonly observed. In 5 cases, due to confluence of large follicles, the histopathologic pattern simulated that of a large B‐cell lymphoma. PCR analysis of the IgH gene rearrangement performed in 33 cases showed a polyclonal pattern in 31 cases and a monoclonal band in 2. In summary, B. burgdorferi‐associated LC can present with misleading histopathologic, immunophenotypic, and molecular features, and integration of all data is necessary for a correct diagnosis.


Journal of Telemedicine and Telecare | 2000

Teledermoscopy - results of a multicentre study on 43 pigmented skin lesions

Domenico Piccolo; Josef Smolle; Giuseppe Argenziano; Ingrid H. Wolf; Ralph Braun; Lorenzo Cerroni; Angela Ferrari; Rainer Hofmann-Wellenhof; Robert O. Kenet; Fabio Magrini; Giampiero Mazzocchetti; Maria A. Pizzichetta; Wilhelm Stolz; Masaru Tanaka; Helmut Kerl; Sergio Chimenti; H. Peter Soyer

We performed a multicentre study to evaluate the agreement between the direct clinical diagnosis and the telediagnosis of 43 cutaneous pigmented lesions. Digital clinical and dermoscopic images of the 43 pigmented skin lesions (11 melanomas, 23 melanocytic naevi, three basal cell carcinomas, three lentigines, two seborrhoeic keratoses and one angiokeratoma) were sent by email to 11 colleagues (six dermatologists, two residents in dermatology, one oncologist, one specialist in internal medicine and one general practitioner) in 10 centres. These 11 colleagues had different degrees of experience in dermoscopy. With histopathology as the gold standard, an average of 85% of the telediagnoses were correct, with results varying from 77% to 95%, whereas face-to-face diagnosis by an expert dermatologist was correct in 91% of cases. The kappa value for all participants ranged from 0.35 to 0.87. The results confirm that teledermoscopy can be a reliable technique for the diagnosis of pigmented skin lesions but one that will depend on the expertise of the observer.


The American Journal of Surgical Pathology | 2002

Cutaneous lymphomas with prominent granulomatous reaction: a potential pitfall in the histopathologic diagnosis of cutaneous T- and B-cell lymphomas.

Alessandra Scarabello; Bernd Leinweber; Marco Ardigò; Arno Rütten; Alfred C. Feller; Helmut Kerl; Lorenzo Cerroni

The presence of a granulomatous reaction in lesions of cutaneous lymphomas has been described in the past in several cases. Especially in mycosis fungoides, a “granulomatous” variant of the disease has been well characterized. We studied the clinicopathologic features of cutaneous lymphomas with prominent granulomatous reaction, including both cutaneous T-cell lymphomas and B-cell lymphomas (primary cutaneous lymphoma 22, secondary cutaneous lymphoma one). Biopsies of 23 patients with histopathologic features of cutaneous T-cell lymphoma or cutaneous B-cell lymphoma with prominent granulomatous reaction were included in this study. A prominent granulomatous reaction was defined as the presence of a granulomatous component exceeding 25% of the dermal infiltrate. There were 14 cases of mycosis fungoides, two of subcutaneous panniculitis-like T-cell lymphoma, four of small/medium pleomorphic T-cell lymphoma, one of follicle center cell lymphoma, one of large B-cell lymphoma, and one of secondary cutaneous peripheral T-cell lymphoma. Altogether, a prominent granulomatous reaction could be observed in 1.8% of all patients with cutaneous lymphoma (primary or secondary) registered in the files of the Department of Dermatology of the University of Graz (Graz, Austria), demonstrating that there is a distinct, albeit small, proportion of cases revealing this peculiar reaction pattern. In seven cases a misdiagnosis of granulomatous dermatitis preceded the correct diagnosis for a period of 1–216 months, suggesting that sequential biopsies and complete phenotypic and molecular genetic analyses should be carried out in cases of “unusual” granulomatous dermatitis.

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Josef Smolle

Medical University of Graz

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Lorenzo Cerroni

Medical University of Graz

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Peter Wolf

Medical University of Graz

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Ingrid H. Wolf

Medical University of Graz

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Erika Richtig

Medical University of Graz

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