Lipoma of the parotid gland.

We describe three cases of parotid gland lipoma, a relatively rare, asymptomatic, slow growing, freely movable, soft tissue mass. Preoperative clinical diagnosis is generally difficult but MRI using fat saturation techniques provides accurate diagnostic information regarding this benign parotid gland tumor, enabling better treatment planning.

[Orbital MALT lymphomas: clinicopathological correlation]. / Orbitale MALT-Lymphome: Klinisch-pathologische Korrelation.

BACKGROUND: Extranodal MALT lymphomas are slow growing tumors of B-cell origin which may be found in the orbit. They are associated with mucosa and epithelial structures. PATIENTS AND METHODS: We present eight patients with biopsy confirmed orbital MALT Lymphomas. The diagnostic imaging techniques are described. Histopathological and immunohistological analysis showed typical findings of MALT lymphomas. RESULTS: After staging six patients had radiation therapy. Two patients refused treatment due to lack of discomfort. CONCLUSIONS: MALT lymphomas should be considered in the differential diagnosis of orbital tumors. While ultrasonography and MRI are needed to determine the extension of these tumors, their identification requires excision or biopsy with histological/immunohistochemical analysis, especially in view of new treatment options.

Corneal calcification following intensified treatment with sodium hyaluronate artificial tears.

AIM: To report a potential adverse effect of intensified treatment with sodium hyaluronate artificial tears. METHODS: Five cases of deep calcium deposition in the cornea associated with ocular surface disease and frequent use of hyaluronic acid artificial tears are described. All patients used one formulation of phosphate buffered hyaluronate eye drops when rapid calcification developed. All eyes required corneal graft surgery for visual rehabilitation. Specimens at keratoplasty were available for light microscopy and investigation by dispersive x ray analysis. The phosphate concentration in the medication used for topical treatment was measured and compared to alternative hyaluronate preparations. RESULTS: Light microscopy showed dense mineralisation of the entire stroma. The crystalline deposits consisted of hydroxyapatite, Ca5(PO4)3OH. A 50-fold higher concentration of phosphate was measured in the sodium hyaluronate eye drops used for treatment (50.9 mmol/l) when compared with normal serum. The other hyaluronate formulations showed phosphate concentrations from <0.1 mmol/l to 10.9 mmol/l. CONCLUSIONS: The hyaluronate artificial tear formulation "Hylo-Comod" favours the formation of insoluble crystalline calcium phosphate deposits in presence of epithelial keratopathy. This is because of its high phosphate concentration and typically frequent instillation. Manufacturers and prescribers should be aware that topical preparations may contain considerable amounts of phosphate which may lead to sight threatening corneal complications.

[Incidental finding: left sided solid adrenal mass]. / Zufallsbefund: Linksseitige solide adrenale Raumforderung.

In a 49 year old male patient diagnostic evaluation of pneumonia performed by computed tomography revealed a left sided adrenal mass. The results of laboratory examination and MR-imaging of the adrenal glands suggested a hormonal inactive adrenal adenoma. Two years later, due to an increase in size, a surgical procedure was performed which revealed a gastrointestinal stromal tumor of the posterior gastric wall, rather than the suspected adrenal mass. Radiologic evaluation of adrenal masses and the clinical and pathologic characteristics of stromal tumors are discussed.

Dual role of the IL-12/IFN-gamma axis in the development of autoimmune myocarditis: induction by IL-12 and protection by IFN-gamma.

IL-12 and IFN-gamma positively regulate each other and type 1 inflammatory responses, which are believed to cause tissue damage in autoimmune diseases. We investigated the role of the IL-12/IFN-gamma (Th1) axis in the development of autoimmune myocarditis. IL-12p40-deficient mice on a susceptible background resisted myocarditis. In the absence of IL-12, autospecific CD4(+) T cells proliferated poorly and showed increased Th2 cytokine responses. However, IFN-gamma-deficient mice developed fatal autoimmune disease, and blockade of IL-4R signaling did not confer susceptibility to myocarditis in IL-12p40-deficient mice, demonstrating that IL-12 triggers autoimmunity by a mechanism independent of the effector cytokines IFN-gamma and IL-4. In conclusion, our results suggest that the IL-12/IFN-gamma axis is a double-edged sword for the development of autoimmune myocarditis. Although IL-12 mediates disease by induction/expansion of Th1-type cells, IFN-gamma production from these cells limits disease progression.

Human leukocyte antigen G up-regulation in lung cancer associates with high-grade histology, human leukocyte antigen class I loss and interleukin-10 production.

Immune evasion in lung cancer results from both structural and functional alterations of human leukocyte antigen (HLA) class I molecules and the local release of immunosuppressive cytokines. Recent data suggest that HLA-G, a nonclassical class Ib molecule, is involved in immune evasion by tumor cells. We sought to determine whether HLA-G could contribute to immunescape in lung cancer. All of 19 tumor specimens examined demonstrated detectable membrane-bound (HLA-G1), as well as soluble (HLA-G5) isoform transcription. Nine of 34 (26%) tumors were positive by immunohistochemistry using monoclonal antibody (mAb) 4H84, recognizing all denatured HLA-G isoforms, of which six were positive using mAb 16G1, recognizing soluble HLA-G. HLA-G immunoreactivity correlated with high-grade histology, with HLA-G being preferentially expressed on large-cell carcinomas. In these patients, loss of classical HLA class I molecules was observed to associate with HLA-G protein up-regulation. Moreover, we found interleukin-10 expressed in 15 of 34 (44%) tumors, and in most of the HLA-G-positive cases (7 of 9), suggesting up-modulation of HLA-G by interleukin-10. It is conceivable that HLA-G expression in lung cancer might be one of the ways how the tumor down-regulates host immune response, in addition to interleukin-10 production and HLA class I loss.

Lethal autoimmune myocarditis in interferon-gamma receptor-deficient mice: enhanced disease severity by impaired inducible nitric oxide synthase induction.

BACKGROUND: Interferon-gamma (IFN-gamma) is an essential cytokine in the regulation of inflammatory responses in autoimmune diseases. Little is known about its role in inflammatory heart disease. METHODS AND RESULTS: We showed that IFN-gamma receptor-deficient mice (IFN-gammaR(-/-)) on a BALB/c background immunized with a peptide derived from cardiac alpha-myosin heavy chain develop severe myocarditis with high mortality. Although myocarditis subsided in wild-type mice after 3 weeks, IFN-gammaR(-/-) mice showed persistent disease. The persistent inflammation was accompanied by vigorous in vitro CD4 T-cell responses and impaired inducible nitric oxide synthase expression, together with evidence of impaired nitric oxide production in IFN-gammaR(-/-) hearts. Treatment of wild-type mice with the nitric oxide synthetase inhibitor N:-nitro-l-arginine-methyl-ester enhanced in vitro CD4 T-cell proliferation and prevented healing of myocarditis. CONCLUSIONS: Our data provide evidence that IFN-gamma protects mice from lethal autoimmune myocarditis by inducing the expression of inducible nitric oxide synthase followed by the downregulation of T-cell responses.

[Malignant lymphoma of the larynx: a case report and review of the literature]. / Das maligne Lymphom des Larynx: Fallbericht und Literaturübersicht.

BACKGROUND: Malignant lymphoma of the larynx are rare tumors and represent less than 1% of primary malignant laryngeal tumors. CASE REPORT: In this case report we present a case of a diffuse large B-cell lymphoma of the larynx. Clinical presentation, diagnostic approach, staging and differential diagnosis as well as therapy and prognosis are discussed in relation to the available literature. CONCLUSIONS: Lymphomas primary to the larynx are non-Hodgkin-lymphomas and are predominantly located in the supraglottic larynx. The presenting symptoms and signs include dysphagia, dysphonia, dyspnea which on occasion can be severe, and enlarged cervical lymphoma. B-symptoms are mostly not present. Indirect laryngoscopy reveals a globoid submucosal faintly pink tumor mass. The diagnosis rests on histological examination of a biopsy specimen. Benign tumors, squamous cell carcinoma and other lymphoproliferative diseases have to be excluded from the differential diagnosis. Extensive tumor staging is necessary before radiotherapy or chemotherapy. Surgery is not indicated, even in localized disease. Prognosis is good in the most often localized laryngeal non-Hodgkin-lymphomas (stage IE and IIE) and generalization is rare. Hence, supraglottic submucosal laryngeal tumors can represent non-Hodgkin-lymphomas. Biopsy and subsequent histological examination are essential for correct diagnosis.

Linking immune-mediated arterial inflammation and cholesterol-induced atherosclerosis in a transgenic mouse model.

Arterial inflammatory responses are thought to be a significant component of atherosclerotic disease. We describe here, using a transgenic approach, the mutual perpetuation of immune-mediated arterial inflammation and cholesterol-induced atherosclerosis. Mice expressing the bacterial transgene beta-galactosidase exclusively in cardiomyocytes and in smooth muscle cells in lung arteries and the aorta (SM-LacZ), and hypercholesterolemic apolipoprotein E-deficient SM-LacZ mice (SM-LacZ/apoE(-/-)) developed myocarditis and arteritis after immunization with dendritic cells presenting a beta-galactosidase-derived immunogenic peptide. Hypercholesterolemia amplified acute arteritis and perpetuated chronic arterial inflammation in SM-LacZ/apoE(-/-) mice, but had no major impact on acute myocarditis or the subsequent development of dilated cardiomyopathy. Conversely, arteritis significantly accelerated cholesterol-induced atherosclerosis. Taken together, these data demonstrate that the linkage of immune-mediated arteritis and hypercholesterolemia favors initiation and maintenance of atherosclerotic lesion formation. Therapeutic strategies to prevent or disrupt such self-perpetuating vicious circles may be crucial for the successful treatment of atherosclerosis.

[Diagnosis and course of myocarditis: a survey in the medical clinics of Zurich University Hospital 1980 to 1998]. / Diagnose und Verlauf bei Myokarditis: eine Erhebung in den Medizinischen Kliniken des Universitätsspitals Zürich im Zeitraum von 1980 bis 1998.

The clinical picture of myocarditis/myopericarditis is of importance in differential diagnosis, especially in younger patients with suspected myocardial infarction. Myocarditis/myopericarditis commonly presents with chest pain, and the diagnosis is usually established on clinical grounds. However, endomyocardial biopsy is necessary to confirm the diagnosis. We evaluated the characteristics of acute myocarditis over the years 1980-1998 in 54 patients of the Department of Medicine of the University Hospital, Zurich. Two to 6 patients per year were hospitalised with this diagnosis. In most cases the diagnosis was established by a combination of criteria, such as a preceding infection of the upper respiratory tract, thoracic pain, ST segment elevations in different precordial leads followed by T wave inversions, arrhythmias, elevation of cardiac enzymes, reversible hypokinesia by echocardiography and normal coronary arteries. At least 3 of 5 criteria were requested. In a first step we analysed retrospectively all patients with acute myocarditis/myopericarditis in the years 1980-1993. Among 30 cases of acute myocarditis/myopericarditis the following causes could be identified: one influenza B, one Toxoplasma gondii infection, 2 Epstein-Barr infections and one bacterial myocarditis with gram-negative rods. The aetiology of the other 25 cases remained unknown. The majority of myocarditis/myopericarditis healed without complications. One patient with Epstein-Barr myocarditis and one with Toxoplasma gondii infection died. Two patients developed dilated cardiomyopathy. In a second phase we analysed prospectively all cases with acute myocarditis/myopericarditis over the period 1994-1998: 24 patients with acute myocarditis/myopericarditis were hospitalised. At that time coronary angiography and endomyocardial biopsies were performed more frequently. We found 2 patients with giant cell myocarditis and 2 with Toxoplasma gondii infection and HIV, all of whom died. In addition, there were 2 patients with eosinophilic myocarditis, one with Lyme carditis, one with Epstein-Barr myocarditis, one with myopericarditis after Campylobacter enteritis and one histologically proven myocarditis after pneumonia with Haemophilus influenzae. The aetiology of the remaining 13 cases with myocarditis/myopericarditis could not be established. Three patients with probable viral myocarditis developed cardiogenic shock requiring intraaortic balloon pump, and fully recovered. The patient with Lyme carditis manifested with total atrioventricular block and was treated with a temporary pacemaker. One patient with lymphocytic myocarditis required heart transplantation because of terminal heart failure and one female patient with histologically proven diffuse lympho-monocytic myocarditis died of cardiogenic shock. All the other cases healed without complications. Serologies are of little diagnostic value and should be restricted to serologies with therapeutic implications. We believe that the apparent increase in myocarditis/myopericarditis in recent years is a result of better diagnostic tools, such as more specific cardiac enzyme tests, coronary angiography and endomyocardial biopsies. In most cases the therapy remains symptomatic. In elected, severe cases steroids and other immunosuppressive drugs are sometimes used.

Malakoplakia of the colon in an infant with severe combined immunodeficiency (SCID) and charge association.

We report on malakoplakia of the colon observed in a six month old girl in a setting of severe combined immunodeficiency (SCID) and a malformational syndrome termed CHARGE association. By the age of six months, hemorrhagic diarrhea had developed, and multiple ulcers were seen at colonoscopy. The biopsy specimen showed ulcerating malakoplakia. Immunodeficiency was primarily reflected by deprivation of CD4 cells in the peripheral blood, and CT scans failed to detect structures consistent with a normal thymus. There were also polylymphadenopathy and chronic erythroderma. The lymph node showed extreme hypoplasia of the follicular cortex and marked expansion of the paracortex. B cell counts progressively declined, and plasma cells were absent both in intact mucosa of the colon and in a lymph node. The patient died at eighteen months of respiratory failure following recurrent airway infections. Pediatric malakoplakia of the colon, though rare, may be regarded as an example of opportunistic bacterial infection in an immunocompromised host. Combined immunodeficiency (CID) has to be considered in such instances, in particular when malformational syndromes coexist affecting the development of the thymus.

Primary cutaneous T-cell-rich B-cell lymphoma and Hodgkin's disease in a patient with Gardner's syndrome.

A 50-year-old patient, suffering from familial polyposis (Gardner's syndrome), initially presented with several nodules on his left arm. Histological examination revealed primary cutaneous T-cell-rich B-cell lymphoma (TCRBCL). Staging procedures failed to detect any systemic involvement. Three years after total excision of the tumours, the patient presented with a non-specific dermatitis, enlarged axillary lymph nodes and splenomegaly. Histological and immunohistochemical examination of lymph node and spleen biopsy specimens resulted in the diagnosis of Hodgkin's disease (HD) of the nodular sclerosis type. Sequence analysis of single cells micromanipulated from skin and from lymph node lesions indicated that both lymphoma infiltrates were derived from the same precursor germinal centre B-cell clone. This is a case showing a clonal relationship between TCRBCL and HD, providing support to the B-cell origin of Hodgkin and Reed-Sternberg cells.

Gene expression profiling of low-grade diffuse astrocytomas by cDNA arrays.

Diffuse astrocytoma WHO grade II is a well-differentiated, slowly growing tumor that has an inherent tendency to progress to anaplastic astrocytoma (WHO grade III) and, eventually, to glioblastoma (WHO grade IV). Little is known about its molecular basis, except for p53 mutations that are found in >60% of cases. In a search for additional genetic alterations, we carried out gene expression profiling of 11 diffuse astrocytomas using cDNA expression arrays. Expression of six genes (TIMP3, c-myc, EGFR, DR-nm23, nm23-H4, and GDNPF) was detected in 64-100% of diffuse astrocytomas, but not in nontumorous brain tissue. Seven genes (AAD14, SPARC, LRP, PDGFR-alpha, 60S ribosomal protein L5, PTN, and hBAP) were found to be up-regulated more than 2-fold in 20-60% of cases, whereas 11 genes (IFI 9-27, protein kinase CLK, TDGF1, BIN1, GAB1, TYRO3, LDH-A, adducin 3, GUK1, CDC10, and KRT8) were down-regulated to less than 50% of normal levels in 64-100% of cases. Semiquantitative conventional reverse transcription-PCR was performed for 11 genes, 9 of which showed an expression profile similar to that obtained with cDNA expression arrays. Immunohistochemical staining for SPARC showed cytoplasmic immunoreactivity of neoplastic cells in all diffuse astrocytomas analyzed. These results indicate significant changes in gene expression in diffuse astrocytomas, but it remains to be shown which of these are causally related to the transformation of glial cells.

Assessment of peritoneal tolerance of a new MR blood pool contrast agent in rabbits.

OBJECTIVE: Fast 3D MR angiography in conjunction with a new blood pool contrast agent (iron oxide crystals) is a recently described method for detection and localization of intra-abdominal bleeding sites with high sensitivity and specificity. However, peritoneal reactions to the contrast agent have not yet been investigated. The purpose of this study was to assess the peritoneal tolerance of the contrast agent in an animal experiment. METHODS: Eleven rabbits were intraperitoneally injected with 5 mL diluted NC100150 Injection; two rabbits were used as the control group. Rabbits injected with NC100150 Injection were imaged in pairs at 12, 24, and 48 hours and 3 weeks, and a single rabbit was imaged at 72 hours and 1 and 2 weeks after the intraperitoneal administration of the agent. Immediately after imaging, the rabbits were killed and an autopsy was performed. Samples of peritoneal surfaces and intra-abdominal organs were harvested for histology. MR imaging, gross pathology, and histology were evaluated. RESULTS: MR imaging and gross pathology demonstrated the presence of intraperitoneal contrast agent up to 24 hours after administration. Histology revealed a considerable amount of iron in the peritoneum, mesenteric fat, and lymph nodes within the first 24 hours. In most cases, iron was rapidly cleared from these sites within 2 days; in one animal, however, iron was detectable up to 1 week. No signs of inflammation or fibrosis were detected. CONCLUSIONS: This study shows no evidence of inflammatory reactions or signs of fibrosis after the intraperitoneal application of NC100150 Injection.

Acquisition of the glioblastoma phenotype during astrocytoma progression is associated with loss of heterozygosity on 10q25-qter.

Loss of heterozygosity on chromosome 10 (LOH#10) is the most frequent genetic alteration in glioblastomas and occurs in more than 80% of cases. We recently reported that PTEN (MMAC1) on 10q23.3 is mutated in approximately 30% of primary (de novo) glioblastomas but rarely in secondary glioblastomas that progressed from low-grade or anaplastic astrocytomas. Because secondary glioblastomas also show LOH#10, tumor suppressor genes other than PTEN are likely to be involved. We analyzed LOH on chromosomes 10 and 19, using polymorphic microsatellite markers in microdissected foci showing histologically an abrupt transition from low-grade or anaplastic astrocytoma to glioblastoma, suggestive of the emergence of a new tumor clone. When compared to the respective low-grade or anaplastic astrocytoma of the same biopsy, deletions were detected in 7 of 8 glioblastoma foci on 10q25-qter distal to D10S597, covering the DMBT1 and FGFR2 loci. Six of 8 foci showed LOH at one or two flanking markers of PTEN but did not contain PTEN mutations. LOH on 10p and 19q was found in only one case each. These data indicate that acquisition of a highly anaplastic glioblastoma phenotype with marked proliferative activity and lack of glial fibrillary acidic protein expression is associated with loss of a putative tumor suppressor gene on 10q25-qter.

Transcaval biopsy of retroperitoneal fibrosis.

An additional use of the transjugular hepatic Tru-cut biopsy needle is reported. A periaortic mass was biopsied with this device inserted through the femoral vein under fluoroscopy guidance. Based on the sampled tissue, a diagnosis of idiopathic retroperitoneal fibrosis was made. The procedure was well tolerated, and long-term follow-up confirmed the diagnosis. Transcaval retroperitoneal biopsy may represent an alternative to surgical biopsy of diffuse retroperitoneal disease in high operative-risk patients.