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S Ihrler

Publications and source records attributed to S Ihrler.

At least 19 recordsLinked to original sources
PubMed2006

[Sinonasal undifferentiated carcinoma. A rare and aggressive neoplasm of the nasal cavity and paranasal sinuses].

Sinonasal undifferentiated carcinoma (SNUC) is a rare tumor of the nasal cavity and paranasal sinuses first described in 1986. Olfactory neuroblastoma and SNUC may appear quite similar on histological examination. Due to the fact that olfactory neuroblastoma has a much better prognosis, a distinction with SNUC has to be drawn. We report a case of SNUC and describe the role of immunohistochemistry in making an accurate histological diagnosis. In addition, potential factors influencing the development of SNUC described in the literature and current treatment modalities are discussed. Despite aggressive and multimodal treatment regimens, the outcomes of patients suffering from SNUC have remained dismal. A randomized controlled clinical study could be the basis for determining the optimal treatment for SNUC.

Biomarkers, Tumor↗
PubMed2006

[Craniofacial augmentation with porous polyethylene implants (Medpor: first clinical results].

SUBJECT: Porous polyethylene (Medpor) is an alloplastic material commonly used in craniofacial reconstruction. We report about our first clinical experiences with Medpor for facial augmentation procedures. PATIENTS AND METHODS: We treated 27 patients between 2001 and 2005 (11 female, 16 male) with 48 Medpor-implants. The indications for application of porous polyethylene implants in our clinic were congenital malformations (15), post-traumatic defects (10), and reconstructions after tumor resection (2). The implants were used for nasal/paranasal augmentations (16), for zygomatico-orbital augmentations (18), and for augmentations of the chin and malar region (11). The procedures were performed in a standardized manner. We used prefabricated, self-contoured implants and fixed them subperiosteally with titanium osteosynthesis screws. All operations were performed under general anesthesia. We evaluated the aesthetic results and the ingrowth behavior clinically and histologically. RESULTS: We achieved good aesthetic results and the patients showed no signs of discomfort or rejection. Four patients required a second intervention. These revision surgeries included two cases of local infections and two for aesthetic contouring. The necessary reduction of the implants allowed the harvesting of tissue and implant samples for microscopy. CONCLUSION: Porous polyethylene implants showed a good fibrovascular integration without encapsulation under the light microscope. Giant cells were detected on the surface of the implants. Besides this there was evidence for resorption of the implant material. Fixation with titanium screws is very effective. No implant dislocation or implant fracture occurred. The implants showed high volume stability and were easily handled and contoured. It is not possible to visualize Medpor implants with current imaging techniques, because polyethylene shows no contrast.

Adolescent↗
PubMed2005

[A rare cause of subacute parotitis. The pathogenetic role of crystals from an infarcted Whartin's tumour?].

The etiology of a subacute inflammatory swelling in the area of the right parotid gland in a 62-years old man could not be resolved clinically. The histomorphological examination of the surgical specimen showed an intraglandular area of predominantly chronic histiocytic inflammation with foreign body reaction in the intimate neighbourhood of a small, subtotally infarcted Warthin's tumour. Not birefringent spindle-shaped crystals could be demonstrated both within the parotitis or intraluminally in vital parts of the Warthin's tumour. In terms of the possible causes of the severe intraglandular inflammation, all arguments favour a primary infarction of the Warthin's tumour with the release of intraluminal preformed crystals which secondarily induce a massive inflammation with foreign body reaction, corresponding to the clinical presentation of a subacute parotitis.

Acute Disease↗
PubMed2005

[Salivary gland carcinomas. 1. Epidemiology, etiology, malignancy criteria, prognostic parameters and classification].

Salivary gland carcinomas comprise a rare group of malignant tumors which are difficult to diagnose and treat due to their histopathologic diversity, variable clinical course and anatomic location, particularly with respect to the facial nerve. The present paper summarizes important features of these tumors, including recent advances in their management, i.e., diagnosis, surgery of the primary tumor, neck dissection, radiation therapy, and updates risk factors, criteria of malignancy, and prognostic variables, taking into account the relevant literature. Additionally, the present paper highlights briefly the survival rates of patients suffering from salivary gland carcinomas. The present overview is divided into two parts: the first is focused on epidemiology, etiology, criteria of malignancy, prognostic factors, and tumor classification, while part II discusses the diagnosis and therapy of salivary gland carcinomas.

Carcinoma↗
PubMed2005

[Salivary gland carcinomas Part II. Diagnosis and therapy].

Salivary gland carcinomas comprise a rare group of malignant tumors which are difficult to diagnose and treat due to their histopathologic diversity, variable clinical course and anatomic location, particularly with respect to the facial nerve. The present paper summarizes important features of these tumors, including recent advances in their management, i.e., diagnosis, surgery of the primary tumor, neck dissection, radiation therapy, and updates risk factors, criteria of malignancy, and prognostic variables, taking into account the relevant literature. Additionally, the present paper highlights briefly the survival rates of patients suffering from salivary gland carcinomas. The present overview is divided into two parts: the first is focused on epidemiology, etiology, criteria of malignancy, prognostic factors, and tumor classification, while part II discusses the diagnosis and therapy of salivary gland carcinomas.

Humans↗
PubMed2004

[Chronic circumferential aortic dissection with intimo-intimal intussusception].

A circumferential aortic dissection with so-called intimo-intimal intussusception is a very rare complication of a dissecting aneurysm, in which the sock-like intimal flap is upended in the true lumen by the blood stream. The few cases reported thus far are based on radiological or intraoperative findings in acute dissections. The present postmortem study documents the very rare case of long-term survival of a chronic circumferential dissection with intimo-intimal intussusception.

Aortic Dissection↗
PubMed2000

[Differential diagnosis of lymphoepithelial lesions of salivary glands. With particular reference to characteristic duct lesions].

Several salivary gland diseases present with the histomorphological features of a lymphoepithelial lesion with or without cyst formation. Some of the most important differential diagnoses (Sjögren's syndrome, marginal zone B-cell lymphoma, HIV-associated cystic lymphoepithelial lesion) are systemic diseases and require further investigation and therapy. However, in small biopsy specimens and in cases without relevant clinical information an exact diagnosis may be difficult to obtain. We have recently determined that the characteristic lymphoepithelial duct lesions develop by proliferation of basal cells of striated ducts, while we could not confirm the previously postulated participation of myoepithelial cells ("epimyoepithelial lesion/sialadenitis"). Although these duct lesions are typical of Sjögren's syndrome, they manifest in several diseases of salivary glands, exhibiting characteristic patterns concerning frequency and localization. This review discusses the most important lymphoepithelial diseases of salivary glands with respect to clinical presentation and histomorphology. Particular emphasis is placed on the lymphoepithelial duct lesions.

Diagnosis, Differential↗
PubMed2000

Sjögren's syndrome and MALT lymphomas of salivary glands: a DNA-cytometric and interphase-cytogenetic study.

Few and conflicting cytogenetic data are available concerning the chromosomal constitution of (mainly gastric) extranodal marginal zone B-cell non-Hodgkin's lymphoma arising from mucosa-associated lymphoid tissue (MALT)-type lymphoma. The majority of salivary gland MALT lymphomas are thought to develop from longstanding Sjögren's syndrome/benign lymphoepithelial lesion (BLEL). We tried to achieve a better comprehension of related cytogenetic alterations by comparing DNA-ploidy and numerical chromosomal (#) aberrations, assessed by different techniques of DNA cytometry (image cytometry) and interphase cytogenetics using nonradiographic in situ hybridization (centromere specific probes for #3, 7, 12, 18) on 12 cases of BLEL, 13 low-grade MALT lymphomas (LG-MALT-L) and 4 high-grade MALT lymphomas (HG-MALT-L) of salivary gland. Both techniques were applied on tissue sections preferentially, enabling a reliable measurement of histomorphologically identified areas. No case of BLEL showed cytogenetic abnormalities. Three of 4 HG- and 2 of 13 LG-MALT-L exhibited complex chromosomal gains in nonisotopic in situ hybridization, which were reflected by DNA nondiploidy in image cytometry. In 6 of 13 LG- and lof 4 HG-MALT-L, one or two numerical chromosomal aberrations were demonstrated by nonisotopic in situ hybridization, which could not be resolved by image cytometry. In the 11 DNA-diploid LG-MALT-L, trisomies 18, 3, and 12 were found in 36, 12, and 9%, respectively. In conclusion, comparing BLEL, which showed no chromosomal aberrations, with LG- and HG-MALT-L, an increase in frequency and number of numerical aberrations and DNA nondiploidy was seen. Peritetraploid DNA nondiploidy might be characteristic for HG-MALT-L of salivary gland as it is a rare finding in MALT lymphomas of other sites. It is unclear whether the documented chromosomal aberrations in LG-MALT-L, especially increased rate of trisomy 18, indicate a pathogenic impact or merely reflect genetic instability.

Adult↗
PubMed1999

Gene therapy--phase I trial for primary untreated head and neck squamous cell cancer (HNSCC) UICC stage II-IV with a single intratumoral injection of hIL-2 plasmids formulated in DOTMA/Chol.

Recombinant IL-2 protein has shown many immunostimulatory effects in a variety of human tumors. However, the clinical use of rIL-2 is limited by common and serious side effects after systemic administration. IL-2 expression plasmids may circumvent these drawbacks, producing high local IL-2 concentrations that cause limited or no systemic side effects. Due to the superficial growth of squamous cell carcinoma of the head and neck (HNSCC) are readily accessible for direct intratumoral injection and therefore an optimal target for such a gene therapy approach. There has been evidence for local and systemic activation of immune cells by peritumoral injections of IL-2 in patients with advanced HNSCC (Whiteside et al. 1993; Cortesina et al. 1994; De Stefani et al. 1996). We now perform a placebo-controlled, dose-rising study of the safety and tolerability of a single intratumoral injection of hIL-2 plasmid at four dose levels formulated in DOTMA/Chol in patients with primary untreated head and neck squamous cell cancer (HNSCC) TNM stage II-IV. The patients will be monitored for the occurrence of any adverse reactions to the given medication. In addition, we will determine whether the intratumoral administration of the plasmid induces and or enhances tumor-specific host responses at the immunological and or clinical level.

Carcinoma, Squamous Cell↗
PubMed1999

Lymphoepithelial duct lesions in Sjögren-type sialadenitis.

It is not clear, whether the so-called basal cells of the salivary striated ducts are an independent cell-type distinct from myoepithelial cells, making characterization of the cell proliferation typical of the duct lesions in Sjögren-type sialadenitis/benign lymphoepithelial lesion (BLEL) difficult. An immunohistochemical investigation including different cytokeratin subtypes, alpha-actin, Ki-67 and Bcl-2 was directed at the epithelial cytoskeleton in normal parotid parenchyma (n=8), BLEL (n=12), HIV-associated lymphoepithelial cysts (n=8) and palatine tonsils (n=8). There are profound morphological and functional differences between basal and myoepithelial cells in the normal salivary duct. Development of duct lesions in BLEL arises from basal cell hyperplasia of striated ducts with aberrant differentiation into a multi-layered and reticulated epithelium, characterized by profound alteration of the cytokeratin pattern. This functionally inferior, metaplastic epithelium is similar to the lymphoepithelial crypt epithelium of palatine tonsils. The often postulated participation of myoepithelial cells in duct lesions of Sjögren disease/BLEL cannot be supported. We regard the designations lymphoepithelial lesion and lymphoepithelial metaplasia as the most appropriate.

Adolescent↗
PubMed1996

HIV-related parotid lymphoepithelial cysts. Immunohistochemistry and 3-D reconstruction of surgical and autopsy material with special reference to formal pathogenesis.

Whether lymphoepithelial cysts in the parotid glands in HIV-infected patients develop from pre-existing salivary gland inclusions in intraparotid lymph nodes or from a lymphoepithelial lesion of salivary parenchyma is unclear. To examine their pathogenesis we performed a histological and immunohistochemical study of salivary specimens from 100 AIDS patients in different disease stages. There is a continuous morphological spectrum of changes within the salivary parenchyma, starting with lymphoid stroma infiltration and evolving to characteristic lymphoepithelial duct lesions with a immunohistochemically proven basal cell proliferation and to fully developed ductal cysts. Involvement of myoepithelial cells-postulated in comparable Sjögren-associated duct lesions-is excluded immunohistochemically. Computer-assisted 3-D reconstructions confirm an association of the cysts with the intralobular duct system. Our study disproves the prevailing hypothesis, which suggests that the lymphoid cell compartment of HIV-associated lymphoepithelial cysts stems from pre-existing intraparotid lymph nodes. The results demonstrate that a secondary lymphatic infiltration of salivary parenchyma provokes a lymphoepithelial lesion of striated ducts with basal cell hyperplasia. The frequent progression to a multifocal cystic lymphoepithelial lesion may be supported by ductal compression through a high degree of lymphofollicular hyperplasia in early disease.

Adult↗
PubMed1996

[HIV-associated cysts of the parotid glands. An histomorphologic and magnetic resonance tomography study of formal pathogenesis].

BACKGROUND: Multiple and bilateral parotid Lymphoepithelial cysts (LEC) are encountered in 3-6% of HIV-infected patients. The formal pathogenesis of LEC is controversial. They are thought to develop from embryological salivary gland inclusions in intraparotid lymphnodes. METHODS: Seventeen operative parotid specimens from HIV-infected patients were examined histologically and immunohistologically. Findings of magnetic resonance imaging (MRI) were correlated with the histological results. RESULTS: A continuous spectrum of a lymphoepithelial salivary gland lesion is found, developing initially from a lymphoid infiltration of salivary lobules to lymphoepithelial duct lesions with cystic dilatation up to large ductal cysts (diameter up to 3.5 cm) with highgrade parenchymal atrophy. The ductal and cystic lesions demonstrate an intense basal cell hyperplasia without participation of myoepithelial cells. The MRI findings indicate involvement of the entire tissue of both parotid glands. CONCLUSIONS: The preferred hypothesis of a development of HIV-associated Lymphoepithelial cysts from preexisting salivary lymphnode inclusions cannot be verified. Our results demonstrate a continuous development of the cysts from a Sjögren-like cystic lymphoepithelial lesion of parotid glands. The enormous cystic dilatation of the duct lesions presumably is a consequence of ductal obstruction through basal cell hyperplasia of striated ducts and intense intraglandular lymphofollicular hyperplasia.

Adolescent↗
PubMed1994

A comparison of clinical, pathological and radiological findings with magnetic resonance imaging studies of lymphomas in patients with Sjögren's syndrome.

In the past few years a variety of papers on magnetic resonance imaging (MRI) of the salivary glands have been published, mainly focusing on the evaluation of salivary gland tumors. More recently, non-tumorous lesions have also been examined with this imaging technique. In Sjögren's syndrome (SS) a characteristic inhomogeneous pattern with a "honeycomb-like" appearance of the parotid gland tissue has been shown in the T2-weighted sequence. This study shows MRI findings in four cases of intraglandular lymphoma occurring in patients with SS. Four patients with suspected lymphomas were examined with MRI, following which all lesions were either biopsied or removed. This enabled us to correlate clinical, radiological and pathological findings. Results indicate that MRI is a useful imaging tool in the detection of intraglandular lymphatic infiltrates, although it is not possible to distinguish morphologically between a localized lymphatic infiltrate and an early stage malignant lymphoma. Nevertheless, MRI is considered to be a valuable non-invasive method for deciding whether or not to perform a biopsy. Due to the excellent soft tissue differentiation obtained, it is also helpful for the surgeon to plan and perform a successful biopsy with minimal risk to the facial nerve.

Aged↗
PubMed1994

[Cystic lymphoepithelial lesions in the head and neck area in HIV-infected patients].

Benign lymphoepithelial cysts (BLC) are rare disorders of salivary glands (0.6%). In patients infected by HIV, they are seen more often. In comparison to sporadic BLC, the patients are younger, the diameter of the cysts is up to 5 cm and they are often located bilaterally. At the Department of ENT, Head and Neck Surgery of the Ludwig-Maximilians-University, Munich, ten HIV-infected patients (two females) showed lymphoepithelial cysts (six times bilaterally). One of these revealed a metastasis of a small cell neoplasma near the cysts, another patient showed a non-Hodgkin's lymphoma of low grade malignancy (MALT-type), and one patient additionally had bilateral Warthin's tumours. The BLCs were mostly located in the parotid tail. In three cases, the cysts were found on the inferior border of the parotid and once at the submandibular gland. The age ranged from 27 to 71 years (medium 45.7 years). The mode of HIV infection was homosexuality five times, drug abuse twice, heterosexuality once, and blood products once. In two cases, the channel of transmission was unknown. The majority of the patients showed minor HIV illness (CDC II [n = 2]/CDC III [n = 4]); the rest had advanced immunodeficiency (CDC IV [n = 4]). All the cysts were examined by ultrasonography and NMR. According to the clinical findings and the general stage of health, BLCs were either enucleated (n = 8) or a superficial parotidectomy (n = 5) and selective biopsy of lymph nodes (n = 3) suspected to be malignant were performed.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Cystic masses in the floor of the mouth: value of MR imaging in planning surgery.

OBJECTIVE: The purpose of this study was to determine the value of preoperative MR imaging for planning the best surgical approach for excising cystic masses in the floor of the mouth. In addition, different sequences and slice orientations were compared in order to develop a standard MR examination technique for this purpose. SUBJECTS AND METHODS: Eleven patients with cystic masses in the floor of the mouth were prospectively examined with MR imaging after palpation and sonography. The imaging protocol included T1- and T2-weighted spin-echo sequences, both unenhanced and contrast enhanced. The exact topographic relationship of these cysts to the surrounding muscles and the value of different MR techniques were analyzed. RESULTS: The mylohyoid muscle, which serves as a key structure in determining the exact position of a cystic mass, was visualized in all cases. T2-weighted images facilitated the primary diagnosis of cystic lesions, whereas T1-weighted images allowed the best visualization of anatomic details. Use of gadopentetate dimeglumine did not provide significant diagnostic information. Coronal and axial slices provided the best visualization of the topographic relationship of cyst and muscles. Sagittal slices were helpful only for midline lesions. In two cases, the choice between the intraoral and the cervical surgical approach was altered by MR imaging findings. CONCLUSION: MR imaging facilitates exact visualization of the location and extent of cystic lesions in the floor of the mouth and is useful for determining their relationship to the surrounding muscles. We conclude that MR imaging is an important adjunct to palpation and sonography in planning the best surgical approach.

Adult↗
PubMed1992

[Provocable tumor of the cheek as a manifestation of so-called "infiltrating lipoma" of the masseter muscle].

We report on a 29-year-old male patient, who presented at our outpatient clinic with a 6-year history of progressive swelling of the right cheek. Contraction of the masseter muscle increased the swelling. MR-Imaging revealed a tumor measuring 2 x 3 cm, which was located within the masseter muscle. The histological diagnosis was infiltrating lipoma, which to our knowledge has not been described in this area before. This particular type of lipoma is extremely rare in the head and neck. The diagnostic and therapeutic management of infiltrating lipoma is discussed, and guidelines for adequate follow-up suggested. In addition, the authors review other sites of this tumor and describe its histological characteristics and differential diagnosis.

Adult↗