Follicular dendritic cell tumor of the mesentery

Follicular dendritic cell (FDC) tumor is an exceedingly rare malignant neoplasm and occurs mainly in the cervical lymph nodes. We report a mesenteric FDC tumor occurring in a 66-year-old female, that manifested with intraabdominal multifocal recurrence 7 years after resection of the primary tumor. Histologically, both primary and recurrent tumors were composed of oval to spindle cells with paley eosinophilic cytoplasms, indistinct cell borders, round to elongated nuclei with clear or finely dispersed chromatin, and medium to large nucleoli. Characteristically, the tumor cells were growing in sheets, fascicles, and sometimes in whorls and a storiform pattern. In addition, focal necrosis, nuclear pleomorphism and abnormal mitoses were also observed. The neoplastic cells were intimately admixed with small lymphocytes. The diagnosis was confirmed by positive immunoreactivity with CD21 and CD35 antibodies and by ultrastructural demonstration of convoluted interdigitating cell processes connected by scattered desmosome-like junctions. Although our case showed a low proliferative activity evaluated by MIB-1, multifocal recurrence has occurred. The clinicopathologic features and differential diagnosis of FDC tumors are discussed with the review of the literature.     

Epidemiology of oral cavity tumors

In this study we aimed at evaluating the modifications in the pharmacokinetic profile of cyclosporin A (CyA) after conversion from standard formulation (CyA-ST) to a new formulation (CyA-NF, Sandimmun Neoral) in patients with rheumatoid arthritis (RA). It was an open, crossover study that involved 15 RA patients who were on stabilized treatment with CyA-ST. The patient continued receiving CyA-ST (mean dose of 3.0 +/- 0.7 mg/kg per day) for 3 weeks and then converted 1:1 to CyA-NF for a further 3 weeks. CyA pharmacokinetics were established on day 1 (CyA-ST evaluation) and +21 (CyA-NF evaluation). The results showed that the bioavailability of CyA-NF was greater than that of CyA-ST (AUC tau, bss: 3335 +/- 1300 vs 2667 +/- 1155 ng.h/ml, P = 0.0073; AUC tau, bss ratio 1.26 +/- 0.40 vs 1.0 as reference, P < 0.05), with higher and earlier peak blood concentrations (Cmax: 677 +/- 256 vs 475 +/- 213 ng/ml, P = 0.0329; tmax: 1.5 +/- 0.7 vs 2.6 +/- 1.6 h, P = 0.0720). The pharmacokinetic profile of CyA-NF showed greater between-patient reproducibility (lower CV% for all of the considered parameters). In conclusion, when using CyA-NF instead of CyA-ST, greater and more constant exposure to CyA should be expected.     

Follicular dendritic cells in non-Hodgkin's lymphomas

Follicular dendritic cells (FDC) are restricted to the B-cell regions of secondary lymphoid tissue and to non-Hodgkin's lymphomas derived from the follicular center or the mantle zone. With their cytoplasmic ramifications they form a dense network which contains the B-lymphocytes. In situ, FDC are only detectable at the ultrastructural level or when stained with anti FDC-reagents. On the surface of their dendritic extensions they express transferrin receptors (CD71), the B-cell epitope CD20, class II antigens, the myelomonocytic molecule CD14, the glycoprotein gp50 (CD40), and several receptors for components of the complement system (CD11b, CD21, CD35). Subsequent to an antigen challenge, FDC trap and retain immune-complexes for a long period of time. In vitro FDC and neoplastic lymphocytes spontaneously form small cellular aggregates. This adhesion is mediated by the LFA-1-alpha/beta = ICAM-1, the VLA-4 = VCAM-1, and the ICAM-1 = C3bi- receptor ligand pathways on B-cells and on FDC, respectively. The loss of LFA-1- alpha/beta and ICAM-1 molecules may enable neoplastic lymphocytes to detach from FDC. The monoclonal B-cells now invade new compartments. In vitro, FDC have the capacity to activate resting B-cells and to save them from dying by apoptosis. Signals involved in this activation include cell-surface immunoglobulin and CD40. Immunocytochemistry and autoradiography with single cell suspensions of neoplastic B cells suggest that FDC also provide signals leading to the continued stimulation of lymphoma lymphocytes. During the early stage of HIV infection lymph nodes show an immense follicular hyperplasia, with a massive increase of the dendritic network of FDC. In the later stage of the disease, the continuous involution of the germinal centers is associated with a progressive destruction of FDC.     

Clear cell tumors of the alimentary tract and abdominal cavity

In a population of male workers in two ship maintenance companies (n = 32), a workplace survey was conducted in order to quantify their physical load. Postural load was measured by using the Ovako Working posture Analyzing System. During 7480 observations, working postures, exertion of force and working activities were recorded. Awkward postures of the back occurred in 38% of the worktime, stress on the neck/shoulder region due to one or both arms above shoulder level was present in 25% of the worktime. Forceful exertions during lifting, pushing and pulling activities sometimes exceeded published guidelines for manual material handling. Determinants of physical load could be identified and a hazard evaluation procedure was designed by applying rating schemes to weight various patterns of physical load. Ship maintenance work compared well with other strenuous occupations. Considering the high prevalence of back pain (80%) and neck/shoulder pain (60%), as well as the results of the observation method ergonomic improvements are warranted. Physical load can be reduced by several technical adaptations and applications, and by enlarging task rotation.     

Tenosynovial giant cell tumors: evidence for a desmin-positive dendritic cell subpopulation

Diffuse tenosynovial giant cell tumor (DGCT) could present as a large intra-articular mass (pigmented villonodular synovitis, or PVNS) or as an extraarticular mass, which might be confused with a sarcoma, particularly when growth is destructive and giant cells are few. Prompted by a DGCT in which a subpopulation of cells was desmin positive and in which an erroneous diagnosis of myosarcoma was made, we analyzed the frequency of desmin, myogenin, MyoD1, and muscle-specific actin immunoreactivity in 45 well-characterized GCTs. We also analyzed a subset of these cases with antibodies to smooth muscle actin, as well as macrophage, follicular dendritic cell, extrafollicular dendritic cell, and dermal dendrocyte-associated antigens. Sections from 45 cases of formalin-fixed GCTs (22 DGCTs, 13 cases of PVNS, and 10 localized GCTs) were immunostained for desmin, myogenin, MyoD1, and muscle-specific actin. The eight cases that showed the largest number of desmin-positive cells were immunostained for smooth muscle actin, CD45, CD68, CD21, CD35, cytokeratin 8, and Factor XIIIa. Desmin-positive cells were seen in 20 (43%) of 45 cases: 10 (43%) of 22 DGCTs, 5 (38%) of 13 cases of PVNS, and 5 (50%) of 10 localized GCTs. In contrast, none were positive for any of the other muscle-associated proteins. In almost all of the cases, the desmin-positive cells were large and dendriform, with long processes that interdigitated between adjacent round cells. Desmin immunoreactivity was found in almost 50% of all GCTs, in the absence of positivity for other muscle markers. Desmin immunoreactivity in GCT seemed to be confined to a variably sized subpopulation of large dendritic cells whose exact identity remains uncertain.     

Dermoid cysts of the oral cavity

The authors describe ethiology, clinical picture, diagnosis and treatment of the dermoid cyst of oral cavity floor. They show the advantages after using ultrasonography and computer tomography in treatment of these cysts.     

Coaggregation of oral lactobacilli with streptococci from the oral cavity

The ability of oral lactobacilli to coaggregate with streptococci and actinomycetes was investigated. Of the 7 species of lactobacilli studied, only two were capable of coaggregation and the coaggregation was restricted to streptococci. Lactobacillus salivarius strains (2/4) coaggregated with Streptococcus salivarius, Streptococcus gordonii, Streptococcus crista and tufted Streptococcus sanguis II strains. Lactobacillus fermentum (2/3) coaggregated with S. gordonii and S. sanguis. The coaggregation between L. salivarius and S. salivarius, S. gordonii or tufted S. sanguis II strains was mediated by a protein on the surface of the lactobacilli and was not inhibited by lactose. The coaggregation between L. fermentum and the streptococci was mediated by protein on the surface of the streptococci and was inhibited by lactose.     

Markers for macrophage and osteoclast lineages in giant cell lesions of the oral cavity

PURPOSE: Giant cell lesions of the oral cavity are a well recognized entity. However, the histogenesis of these lesions is still the subject of controversy, with support for both histiocyte/macrophage and osteoclast origins being found in the literature. This study evaluated a set of peripheral giant cell lesions (PGCLs) and central giant cell lesions (CGCLs) for characteristics of both cell types to address this dilemma. MATERIALS AND METHODS: Detection of histiocyte/macrophage characteristics was accomplished immunohistochemically by evaluating for markers specific for this cell type, namely alpha-1 -antichymotrypsin (1 -ACT) and factor XIIIa antibodies. Detection of osteoclast characteristics made use of the fact that osteoclasts possess a unique enzyme, tartrate-resistant acid phosphatase, which can be appreciated by histochemical procedures. RESULTS: A large percentage of the multinucleated cells stained with the 1-ACT (38.08% in PGCLs and 15.84% in CGCLs), while only isolated cells stained for factor XIIIa (1.20% PGCLs, 0.99% CGCLs). Isolated stromal cells also were stained. Virtually all multinucleated cells reacted with the tartrate-resistant acid phosphatase stain (99.26% PGCLs, 98.34% CGCLs), as did a number of the mononuclear stromal cells. CONCLUSIONS: This study supports the contention that GCLs of the oral cavity may arise from precursor cells related to the granulocyte/macrophage line, and may originate from mononuclear cells that express markers for both macrophages and osteoclasts.     

Use of the laser in the oral cavity

Literature on head and neck oncology continues to support the use of lasers in surgery of malignant and premalignant lesions of the oral cavity. This article explores the indications, techniques, results, and complications of laser use for surgery involving these lesions. Highlighted is the carbon dioxide laser, which is well suited for transoral resections of premalignant lesions and early carcinomas in the oral cavity. In this study the local control, the 5-year survival rates, and the postoperative function with the carbon dioxide laser are at least comparable with those obtained using other surgical methods. The neodymium:yttrium-aluminum-garnet laser, which has specific advantages in the treatment of large vascular malformations of the oral cavity because of its unique characteristics, is also discussed.     

Malignant tumors of the oral cavity. Epidemiologic study of 294 cases observed during the decade 1984-1994

MATERIALS AND METHODS: The research has been carried out with the cooperation of Department of Otorhinolaryngology of the "Ospedale S.S. Trinita" in Cagliari, on 294 patients suffering from oral malignant tumours between 1984 and 1994. This kind of disease was studied in relation to age, sex, histological type, and afterwards the examination results were compared to other researchers' studies. All the 294 patients were recorded in the operating theatre's registers. Oral malignant tumours amount to about 45% of the neoplastic systemic pathology. Use and misuse of alcohol, smoking, repeated blows resulting in pre-cancerous lesions including leukoplakia, might be considered the main causes of the origin of oral tumours. RESULTS: Male patients (237) amount to 80.7% of the examined sample, while female ones (57) reach only 19.3%. The part most frequently involved is the tongue (97 cases, 33%), then the area of the lower lip (69 cases, 23.5%), and finally the lower part of the oral space (47 cases, 15.58%). CONCLUSIONS: From the histological point of view, the squamous carcinoma is found more often in the tongue, in the lower oral space and in the lips, while the basal carcinoma in the lower lip rather then in the upper one. A remarkable increase in the squamous carcinoma and a grow in the areas of the tongue has been observed.     

p53 antibodies in the saliva of patients with squamous cell carcinoma of the oral cavity

A significant age dependence of the risk of complete heart block complicating radiofrequency ablation of the AV nodal slow pathway was noticed, with no patients <45 years of age experiencing this complication.     

Bone harvesting from the oral cavity]

BACKGROUND AND METHODS: We examined the effect on health perceptions of a diagnostic workup in 172 patients with suspected multiple sclerosis (MS) using two questionnaires (Mishel, Rand Medical Outcome Study) and three visual analogue scales measuring distress. Patients were categorized into "MS," "not MS," or "still uncertain" groups. RESULTS: Patients with a definitive diagnosis reported a significant decrease in uncertainty (analysis of variance [ANOVA] P = .0004). The Medical Outcome Study showed a slightly worsened perceived current health status (ANOVA P = .02) and future health outlook (ANOVA P = .001) in the MS group compared with the other two groups. Distress over physical symptoms decreased in all three groups and anxiety was more likely to decrease than increase even in those with MS. Prognostic uncertainty distress decreased in the not MS group and still uncertain groups, whereas it remained unchanged in the MS group (P = .9156). CONCLUSION: Significant and generally beneficial changes in patient health perceptions are seen associated with a neurologic workup in suspected MS, irrespective of the final diagnosis.     

Precancerous and cancerous lesions of the oral cavity

The purpose of this article is to provide the clinician with the clinicopathologic characteristics of oral cancer and its precursors. As can be seen by the previous discussion, numerous variables influence the formation of these lesions, and as yet we are unable to predict the progression of any single, premalignant lesion with certainty. Because of this, only astute clinicians, armed with a healthy level of suspicion, will be able to affect the prognosis of oral malignancies by recognizing these conditions at the earliest possible stage.     

Aphthosis of the oral cavity: therapeutic prospectives

After analysing of recurrent aphthous stomatitis the clinical and morphological aspects, the authors consider various therapeutic possibilities. They underline the relationship between therapy and clinical aspects of the pathology.     

Using fluorescence-based human androgen receptor gene assay to analyze the clonality of microdissected dendritic cell tumors

The AGT1 permease is a alpha-glucoside-H+ symporter responsible for the active transport of maltose, trehalose, maltotriose, alpha-methylglucoside, melezitose and sucrose. In wild-type as well as in MAL constitutive strains, alpha-methylglucoside seemed to be the best inducer of transport activity, while trehalose had no inducing effect. Based on the initial rates of transport it seems that the sugar preferentially transported by this permease is trehalose, followed by sucrose.     

Melanoma of the oral cavity. Review of the literature

The location of melanoma in the oral cavity is extremely rare: its frequency varies between 0.2 and 8%. Oral melanoma strikes mainly male subjects and is more frequently seen at the level of the hard palate and gingiva. Today the clinicopathological classification of oral melanoma is not yet clearly outlined, and that is why the skin form is often taken as a reference. The acral lentiginous subtype proves to be the most common in this seat. In many cases (up to 50%) the diagnosis of melanoma is made on lesions which have evolved from the pre-existing pigmented lesions: as a consequence, every pigmented lesion of undetermined origin must be biopsied as a routine. The prognosis often proves poor and the surgical approach, combined with the chemotherapeutic one, is the first choice treatment. Lymph node dissection is not routinely practiced.