Aggressive maxillary squamous odontogenic tumour in a child: histological dilemma and adaptative surgical behaviour.

A case of a maxillary osteolytic tumour is described in a 9-year-old boy. Histological analysis led to an initial diagnosis of benign squamous odontogenic tumour, although this was not straightforward due to swelling, and cellular pseudo-malignant and non-specific signs. Because of the young age of the patient, a local surgical tumourectomy was first chosen with respect to the mixed dentition. For 10 months, the evolution was satisfactory. Then, a very aggressive tumoural recurrence with lip and palate infiltration led to doubts as to the histologic nature of the tumour. Efficient collaboration between several specialized pathologist teams finally confirmed that this was a squamous odontogenic tumour but in a very aggressive form. Radical surgery was then carried out.

Facial malignant peripheral nerve sheath tumors.

BACKGROUND/PURPOSE: Malignant peripheral nerve sheath tumors (MPNSTs) are rare neoplasms, only sporadically reported involving the maxillo-mandibular region (ten cases with CT or MR data). We present here five additional cases with CT and MR findings along with an extensive review of the literature. RESULTS: Accurate diagnosis of MPNSTs is difficult because pathological like radiological criteria are often non specific. Radiological features display a large spectrum of abnormalities from a well-delineated heterogeneous appearance simulating benign schwannoma to extensive erosive patterns. Their development along the mandibular nerve, the absence of any target or central dot sign, their strong predominant peripheral enhancement must suggest the diagnosis of MPNSTs while irregular bone destruction or the detection of poorly defined margins with muscular infiltration are the most reliable criteria of malignancy. Unfortunately, MPNSTs also display a considerably varied histology. Careful clinical and radiological correlation should bring pathologists to examining large samples of the lesion to better evaluate the overall organisation of the lesion and detect some evocative criteria often only present in some areas of the sample as the peculiar curlicue or whorled arrangement of the spindle cells or the alternation of densely cellular fascicles with hypocellular, myxoid zones. Focal, limited immunostaining for S-100 protein is one of the most important additional criterion. CONCLUSION: If accurate early diagnosis often remains difficult, careful correlation of clinical, pathological and radiological data should in most cases suggest a diagnosis of MPNSTs which display a poor prognosis and requires early and adapted treatment.

Design strategy for a simultaneous nitrification/denitrification of a slaughterhouse wastewater in a Sequencing Batch Reactor: ASM2d modeling and verification.

Sequencing Batch Reactor (SBR) was used to treat slaughterhouse wastewater which contains average Chemical Oxygen Demand (COD) concentration of 5000 mg l(-1) and ammonium of 360 mgN l(-1). Nitrification/denitrification process was conducted for nitrogen removal. The influent wastewater as internal carbon source and sodium acetate as an external one was used for completing denitrification to achieve the simultaneous organic matter removal (95-96%) and nitrogen removal (95-97%). In addition, the dynamic SBR simulation model for biological nitrogen removal based on the Activated Sludge Model No. 2d (ASM2d) and GPS-X software is presented. The experimental study for the calibration and validation of the model was carried out using laboratory SBR. The study showed that the model provides a powerful tool to reduce the experimental expenditure and time to find the optimum strategy.

Event-related auditory evoked potentials and amyotrophic lateral sclerosis.

OBJECTIVE: To study event-related potentials and particularly the P300 wave in a group of patients with amyotrophic lateral sclerosis (ALS), as changes in the P300 wave have been observed in many cases of brain damage-inducing cognitive impairment. DESIGN: Case series. SETTING: University hospital. PATIENTS: Twenty patients with ALS were compared with 20 healthy control subjects, with no significant age range and no significant difference in their education level. MAIN OUTCOME MEASURES: Amplitudes and latencies of long-latency auditory evoked potentials for the N100, P200, N200, and P300 waves were measured in the "odd-ball paradigm." Mental status was assessed by the Similarities subtest of the Wechsler Adult Intelligence Scale and by the Rapid Evaluation of Cognitive Function that allows for a mini-neuropsychological testing. The degree of disability was scored on the ALS Severity Scale, which rates bulbar and spinal functions. RESULTS: The latencies of the N100 and P200 waves did not appear to differ between normal and affected subjects; in contrast, the N200 and P300 latencies were significantly longer in the group with ALS. Sixty percent of the patients had a P300 latency more than 2 SDs above the theoretical norm that was established by the linear curve for control subjects. The N100, P200, N200, and P300 amplitudes showed no significant difference between the control subjects and the group of patients with ALS. There was no significant correlation between the N200 and P300 latencies and the disease duration or between the N200 and P300 latencies and the degree of motor impairment. The scores from the Rapid Evaluation of Cognitive Function were significantly lower in the group of patients with ALS than in the group of control subjects. CONCLUSIONS: A subtle cortical cognitive dysfunction is frequently observed in patients with ALS. These findings point also in the same direction as did previous neuropsychological, histological, and positron emission tomographic studies of ALS. Limb motor deficits and speech difficulties make it difficult to study the time course of changes in intellectual function in patients with ALS by using psychometric methods; thus, in the future, cognitive evoked potentials should constitute a fruitful method of testing cognitive function in patients with ALS to follow up their development over time.

Proteoglycans detected by monoclonal antibodies in adenoid cystic carcinoma of salivary glands.

Thirty-two cases of adenoid cystic carcinoma (ACC) of the salivary glands were examined immunohistochemically by monoclonal antibodies to proteoglycans (PG) such as chondroitin 6 sulfate (C6SPG), chondrotin 4 sulfate (C4SPG), dermatan sulfate (DSPG), heparan sulfate (HSPG) and keratan sulfate (KSPG) in conjunction with specific enzymatic digestion. The cribriform structure of ACC consisted of basaloid, myoepithelium-derived, and luminal tumor cells. The myoepithelial tumor cells were positive for PG, whereas luminal tumor cells were unstained. Occasional pseudocysts also gave positive staining for PG. Tubular structures consisting of modified myoepithelial cells indicated a high intensity reaction for C6SPG and C4SPG, and a slight one for DSPG, HSPG, and KSPG. Immunodepositions in solid and cluster structures were comparatively light in terms of PG. Basement membrane in ACC stained strongly for C4SPG, slightly for C6SPG, and very slightly for DSPG, HSPG, and KSPG. In ACC, immunohistochemical staining of PG was regularly positive in myoepithelium-derived tumor cells, but was irregular in other types of tumor cells.

[Lethal midline granuloma of unknown cause: 6 new cases and review of the literature]. / Granulome malin centro-facial de cause inconnue: six nouvelles observations et revue de la littérature.

The term of "lethal midline granuloma" has been used to apply to a number of diseases. In this paper, it is argued that this term should be only a clinical description of a relentlessly progressive destructive lesion of the nose and face. A list of all the possible causes is presented. There is a group of patients who do not correspond to any specific etiology. Reviewing the observations in the literature and our own, we think that such cases are best classified according to their histological appearance. Those without atypical cells (20% of cases) are always localized to the upper respiratory tract, while those with atypical cells (histiocytes?), 80% of cases, may become generalized and/or may evolve to a malignant lymphoma. When localized, both forms (with and without atypical cells) respond very well to high-dose radiation therapy (40 to 60 Gy). In disseminated forms or relapses following radiotherapy treatment, chemotherapy, the only available alternative treatment, has met with little success. We present the clinical and pathological features of six such patients, of whom one had no atypical cells. Radiotherapy produced a clinical remission in five of five cases, but of shorter duration than that reported in the literature. No treatment other than radiotherapy has yet proven to be regularly efficient in this rare and mutilating disease.

Ameloblastic fibrosarcoma of the jaws--report of three cases. Clinico-pathologic, histoenzymological and ultrastructural study.

The ameloblastic fibrosarcoma is a rare variety of neoplasm. Three new cases reported here occurred within preexistent benign odontogenic tumors (ameloblastic fibroma or fibro-odontoma). These large, osteolytic tumors, spreading to adjacent soft parts, recurred after surgical treatment in two cases. One of them had a lethal course, with pleuro-pulmonary, mediastinal lymph node and hepatic metastases. Histologically, these sarcomas show a malignant mesenchymal component and few benign ameloblastic islands, which often disappear after one or several recurrences. Histoenzymologically, a high level of alkaline phosphatase and ATPase activities is always present, a feature not present in common fibrosarcomas. The ultrastructural study demonstrates, in analogy with odontogenic myxomas, clear cells provided with numerous microfilaments, secretory cells and also some fibroblasts and myofibroblast-like cells. In addition to these pleomorphic cells, a great number of peculiar granular cells with numerous lysosomal bodies were also found. The histogenesis of these tumors in unknown. Perhaps the epithelial component, being unable to assume its functions of organization, may initiate the malignant transformation of its odontogenic mesenchyme.

Stromal changes in early invasive breast carcinoma. An immunohistochemical, histoenzymological and ultrastructural study.

The purpose of this work was to detect in periductal connective tissue of breast carcinoma in situ changes induced by intraductal tumor cells before any dehiscence in basement membrane. Histological, electron microscopic, immunohistochemical and histoenzymological methods were used in 3 carcinomas in situ, 4 microinvasive carcinomas and 13 control invasive carcinomas. We could demonstrate a high functional activity of fibroblasts with secretion of mucopolysaccharides and type III collagen around intraductal carcinomas. These changes occurred simultaneously to those of the basement membrane which was either thinning or thickening. Any dehiscence in basement membrane secondarily induced in this periductal stroma the usual changes seen in invasive stroma, peculiarly numerous vascular pedicles, myofibroblasts, elastic material. These periductal stromal changes are interpreted according to recent concepts about the possible influence of tumor cells upon their environment: stimulation of mitotic and metabolic activity of fibroblasts: stimulation of angiogenesis by means of an angiogenic factor.

Scanning electron microscopy of normal, malignant and post radiotherapeutic oral mucosal cells.

A scanning electron microscopic study of 40 oral mucosal smears from healthy controls or patients with cancer of the mouth has enabled a comparison of the "external" characteristics of normal, malignant and dysplastic (post-radiotherapeutic) cells. Normal cells, particularly the cells of the superficial epithelial layers, were characterized by well-defined polarized external protrusions with ridges on the upper surface and microvilli on the under surface. In cancer cells, both the shape and arrangement of these formations were profoundly altered. Dysplastic cells presented an intermediate appearance which was sufficiently characteristic to allow them to be distinguished from neoplastic cells.

An immunohistochemical study of the distribution of lysozyme, lactoferrin, alpha 1-antitrypsin and alpha 1-antichymotrypsin in salivary adenoid cystic carcinoma.

The immunohistochemical expression of lysozyme (Ly), lactoferrin (La), alpha 1-antitrypsin (alpha 1-AT), and alpha 1-antichymotrypsin (alpha 1-Ach) was described, and their distributions were compared to each other in 28 cases of adenoid cystic carcinoma (ACC) of the salivary glands. ACC materials were obtained from the parotid gland (7), the submandibular gland (4), the sublingual gland (8), and minor oral salivary glands (9). Histopathologically, ACC was classified into cribriform (14), tubular (3), and basaloid or solid patterns (11). Positive staining for Ly was found in 1 case of solid ACC in the sublingual gland; La was found in 4 cases (2 cribriform, 1 tubular, 1 basaloid) in the sublinguals (3) and parotid glands (1); alpha 1-AT was found in 6 cases and alpha 1-Ach in 17 cases. The immunohistochemical localization of Ly and La was usually confined to luminal tumor cells of tubulo-ductal structures, irrespective of the pathologic types. Positive staining for alpha 1-AT and alpha 1-Ach appeared in tumor cells of cribriform, tubular and solid ACC. Tumor cells with positive La staining coincided with a positive reaction to alpha 1-AT and alpha 1-Ach, and tumor cells with alpha 1-AT positive deposition were also positive for alpha 1-Ach. The contents of pseudocysts in the cribriform pattern showed a positive reaction to La, alpha 1-AT, and alpha 1-Ach. Of the 28 cases of ACC, positive expressions for Ly, La, alpha 1-AT and alpha 1-Ach were found with a high frequency of alpha 1-Ach staining (17 in 28 cases were positive). In sublingual ACC (8), 7 cases were positive for immunohistochemical reactions. Co-expression or simultaneous expression for Ly, La, alpha 1-AT, and alpha 1-Ach in ACC suggest that tumor cells are protected from proteolysis or degradation.

Effects of estradiol and promegestone on human breast cell cultures. An ultrastructural study.

Effects of estradiol (E2) and promegestone (R 5020) were tested on primary cultures of epithelial human breast cells prepared from surgical specimens of reduction mammoplasty. Comparative morphological studies were performed by means of transmission and scanning electron microscopy in cells without any hormonal adjunction and in those previously treated with E2 or E2 + R 5020. The results were as follows: In basal medium used as control the majority of epithelial cells, although well-differentiated, remained flat with few microvilli, well-developed Golgi apparatus and rough endoplasmic reticulum, was obvious. R 5020 added with E2 increased differentiation of epithelial cells covered with scarce long and branched microvilli, but reduced the turn-over of young cells. E2 seemed to generate more active proliferation of cells. R 5020 inhibited this effect and induced a higher differentiation of mammary epithelial cells.

Evaluation of combinations of titanium, zirconia, and alumina implants with 2 bone fillers in the dog.

The quality of the tissue-implant interface was evaluated using light and scanning electron microscopy with morphometric analysis. Nine dogs were implanted with 3 types of dental implants (titanium, zirconia, or alumina). A total of 24 dental implants was placed in mandibular bone previously filled with coral carbonate calcium (corail) or hydroxyapatite. The study results in breaking the concept of osseointegration into 2 phases: "osseocoaptation," which concerns only the interface (physical contact between the implants and the bone without interpenetration process), and "osseocoalescence," which relies on an interpenetration of the bioactive material, which almost entirely disappears, being substituted by newly formed bone. There was no significant statistical difference between the 3 types of implants. Both fillings showed good ossecoalescence properties. However, hydroxyapatite led to fibrous encystment, preventing osseocoaptation of implants. In contrast with calcium carbonate filling.

Cherubism. Histo-enzymological and ultrastructural study.

The 3 cases of cherubism reported affected the mandible. They were all studied by means of histo-enzymological and ultrastructural methods. This study demonstrated 3 stages in the morphological evolution of the disease, corroborated by clinical data. The 1st stage was characterized by an osteolytic granuloma with round, fusiform and giant-cells and a high level of activity of acid phosphatase. The 2nd stage showed repair with proliferation of highly active fibroblasts (increase in activity of leucine aminopeptidase). The 3rd stage exhibited an osteogenesis with high activity of alkaline phosphatase and ATPase. The pathogenesis of this rare osteodysplasia is discussed.

Mesenchymal chondrosarcoma of the jaws. Report of four cases.

Mesenchymal chondrosarcoma (MCS), described in 1959 by Lichtenstein & Bernstein, is a very rare malignant tumour. Only 46 cases have been previously reported in the jaws. Over a period of 30 years, four chondrosarcomas of mesenchymal type (of which one has already been published in 1987 with a three-month follow up) were treated in our department. Two patients have been followed for more than 17 years, of whom one has died of an intracranial extension and the other is still alive after surgical treatment of numerous recurrences and metastases. The two others are tumour-free with a follow up of 18 months and 11 years respectively. Histological, epidemiological and clinical features and treatment of MCS are discussed relevant to the data published in the literature.

Scanning electron microscopy in oral cytology.

Sixty-three cell smears from oral mucosa were studied by scanning electron microscopy. Among them, smears from ten healthy controls showed three kinds of cells: flat (superficial) cells with linear anastomosing microridges and microvilli; polygonal (intermediate) cells with well-defined crests between their faces and numerous microvilli; and round (parabasal) cells entirely covered by microvilli. Twenty-five smears from patients with untreated squamous-cell carcinoma showed enlarged polymorphous cells (round, globular, and elongated); microvilli, variable in their dimensions, were irregularly distributed on their surfaces. Eighteen smears from patients with severe epithelial dysplasia showed polymorphous cells with discontinuous but obvious edges separating their faces and with irregular microvilli and ridges. Nine smears were also performed in patients with various other mucosal lesions (lichen planus, leukoplakia, white sponge naevus, pemphigus vulgaris, and herpes). All of these smears were studied comparatively between examination of smears and biopsies by light microscopy. The smears were truly reliable, particularly for distinguishing between dysplastic and tumoral cells.

[Small cell carcinoma. Incidence, histopathology and anatomical features. Analysis of 465 autopsied bronchopulmonary carcinomas (author's transl)]. / Le cancer bronchique à petites cllules: fréquence, histopathologie et évolution anatomique; analyse d'un recrutement nécropsique de 465 cancers bronchopulmonaires.

465 patients with broncho-pulmonary malignant tumors have been autopsied. Small cell carcinoma was diagnosed in 22.5 per cent of these patients. The histo-cytological variants of these tumors (lymphocytoid, polygonal, fusiform and polymorphic) had the same general characteristics (age, sex, survival) and a similar clinical course. Grossly and histologically, the bronchial tumor, always located in proximal bronchial tree, largely involved the mediastinum. Metastases were peculiarly frequent to the liver (69%), to bone (64.2%) and to the central nervous system (36.2%). Three Schwartz-Bartter syndromes and two Denny Brown sensitive neuropathies were noted in this statistical study.

[Cardiac myxoma. Ultrastructural study of 2 cases]. / Myxome cardiaque. Etude ultrastructurale de deux observations

From amongst a series of eight cardiac myxomas, two were studied by electron microscopy, which enabled us to identify, amongst varous cell types, two main ones. One of these was a secretory cell with Golgi apparatus and secretory vacuoles, and the other was of the expected type, with microfilaments showing signs of progressive differentiation towards either muscle or epithelial structure. A morphological picture of this sort tends to lend support to the concept of a dysgenetic origin for these tumours, arising from pluripotent embryonic cells sequestrated in the region of the fossa ovalis.

[Pathology of degenerative aortic valve insufficiency]. / Anatomie pathologique des insuffisances aortiques dégénératives.

The authors studies 154 cases of degenerative aortic regurgitation which presented macroscopically with atrophic changes of the valve and sometimes with hypertrophy and calcification. Histologically, the essential abnormality was the finding of mucopolysaccharide deposits dissociating the corpus spongiosa from the corpus fibrosa. Depending on the importance of these lesions, three degrees of severity can be defined, the most extensive (84% of our patient population) appearing to be typical of the disease. In addition, mild mitral valve prolapse (5%) and medial necrosis of the aortic wall (80% of patients undergoing aortic biopsy) were observed. These morphological features are on the whole quite different to those of other aortic valve pathologies (rheumatic, endocarditis). However, the border line with other pathologies with a similar anatomopathological substratum is less clearly defined: genetic abnormalities (Marfan's syndrome, Lobstein's disease, etc...) or age-related degenerative disease. The pathogenesis is not clearly understood but could be related to regional disturbances in collagen metabolism with collagenolysis predominating.

[Intermediate and late changes in human cardiac graft]. / Modifications vasculaires semi-tardives et tardives du greffon cardiaque humain.

Chronic rejection, the most serious complication in long-term survivors of cardiac transplantation, was studied in 5 cardiac grafts obtained at retransplantation and in 15 post-mortem studies of patients who had survived 3 months to 10 years after transplantation. The usual clinical presentation was cardiac failure. Coronary angiography was performed in several cases and showed narrowing and non-opacification of small arteries often accompanied by thrombosis. Histology showed three types of vascular rejection: the most characteristic one, usually observed after the 6th month, was a stenosing fibrous endarteritis; another type of rejection, occurring earlier, was associated with acute myocardial rejection and presented as an inflammatory arteritis; the third type of vascular rejection was accompanied by widespread atheromatous lesions. The significance and pathogenesis of these lesions are discussed with respect to the clinical context with electron microscopic and immuno-histochemical data.

[Cells of the conduction pathways of the human bundles of His. Histoenzymologic and ultrastructural study]. / Les cellules des voies de conduction dans le faisceau de His humain. Etude histoenzymologique et ultrastructurale.

A human His bundle was studied two hours after death by histoenzymological techniques and electron microscopy. The pathway had a much higher cholinesterase activity than the working myocardium, due to its richness in nerve endings: this was confirmed by electron microscopy which also distinguished "common" contractile cells (working cells) from P type and "intermediary" cells; those were by far the most common, presenting an ultrastructure identical to that of the Purkinje cells, classically described in the bundle branches alone. These findings and the unique longitudinal architectural organisation of the His bundle, confirm the studies of JAMES and may explain the rapidity of conduction in this structure.