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Biomedical subjects

R Sciot

Publications and source records attributed to R Sciot.

At least 163 records · Page 9Linked to original sources
PubMed1995

Giant cell rich parosteal osteosarcoma.

A parosteal osteosarcoma of the distal femur with a typical radiographic and macroscopic appearance is reported. On histology the tumour was dominated by large numbers of osteoclast-like giant cells in a fibro-osseous background and islands of immature bone. Most of the neoplastic bone lacked osteoblastic rimming. There was no spatial relationship between the giant cells and areas of haemorrhage. Signs of 'dedifferentiation' were lacking. Cytogenetic a analysis revealed telomeric associations which are frequently found in giant cell tumours of bone. Parosteal osteosarcoma may, on histological appearances, hardly be recognizable as malignant. In addition, unusual changes such as abundant giant cells may be misleading in the absence of clinico-pathological correlation.

Adult↗
PubMed1995

Angiosarcoma of the larynx.

The morphological and immunohistochemical features of a laryngeal angiosarcoma are described. Initially, the tumour was interpreted as a poorly differentiated squamous cell carcinoma. The laryngectomy specimen contained an extensive and haemorrhagic tumour consisting of irregular and dissecting vascular spaces delineated by pleomorphic endothelial cells. In addition to these obvious angiosarcomatous areas, islands of more compact growing tumour cells were present, reminiscent of a poorly differentiated squamous cell carcinoma. On immunohistochemistry, the tumour cells expressed factor VIII, Ulex europaeus I lectin, CD31 and vimentin. There was no expression of cytokeratin or epithelial membrane antigen. Angiosarcoma of the larynx is very rare and should be differentiated from a pseudo-angiosarcomatous carcinoma.

Antigens, Differentiation, Myelomonocytic↗
PubMed1995

Monosomy 22 in a malignant peripheral nerve sheath tumour of the kidney in childhood: a genetic link with other malignant paediatric renal neoplasms?

A recurrent malignant spindle cell neoplasm of the kidney, occurring in a 11-year-old girl and corresponding to a malignant peripheral nerve sheath tumour is reported. The neurogenic differentiation was substantiated by the presence of PGP 9.5 neurofilament and S-100 protein positivity and by the ultrastructural features. Cytogenetic analysis revealed monosomy of chromosome 22 in the tumour while the constitutional karyotype was normal. Primary malignant peripheral nerve sheath tumour of the kidney is extremely rare and should, on morphology, be differentiated from stromal predominant Wilms' tumour and clear cell sarcoma of kidney. Involvement of chromosome 22 has been described in a number of malignant renal tumours of childhood, such as Wilms' tumour (deletion), clear cell sarcoma (translocation), and rhabdoid tumour (deletion and translocation), thus suggesting common molecular mechanisms in pediatric malignant renal tumours.

Child↗
PubMed1995

Two categories of synovial sarcoma defined by divergent chromosome translocation breakpoints in Xp11.2, with implications for the histologic sub-classification of synovial sarcoma.

Molecular analysis of a new series of synovial sarcomas confirms that t(X;18)(p11.2;q11.2) breakpoints occur at two distinct regions on Xp designated SS1 and SS2. Breakpoint position correlates with tumor phenotype. Monophasic tumors with no evidence of glandular components have breakpoints within the SS2 region in Xp11.21, and biphasic tumors with a focal poorly differentiated or extensive glandular structure have breakpoints within the SS1 region in Xp11.23.

Adolescent↗
PubMed1995

t(9;22)(q22-31;q11-12) is a consistent marker of extraskeletal myxoid chondrosarcoma: evaluation of three cases.

Three cases of extraskeletal myxoid chondrosarcoma with typical histologic and ultrastructural features were investigated cytogenetically. All three cases showed a reciprocal chromosome translocation characterized as t(9;22)(q22-31)(q11-12), thus confirming the findings in three previously karyotyped cases of extraskeletal myxoid chondrosarcoma in the literature. These data add significantly to the evidence of t(9;22) being diagnostic for extraskeletal myxoid chondrosarcoma. Other previously published cases with a range of complex karyotypes were less well defined morphologically. In cases with limited diagnostic material this karyotype might facilitate distinction from myxoid liposarcoma, which consistently shows t(12;16). Clear cell sarcoma, Ewing's sarcoma/primitive neuroectodermal tumor, and desmoplastic round cell tumor also show involvement of chromosome 22 with formation of a hybrid gene between the Ewing's sarcoma gene on band q12 and a transcription factor gene. Whether rearrangement of the Ewing's sarcoma gene is also present in extraskeletal myxoid chondrosarcoma is not clear at present. Cloning of the (9;22) translocation might provide important clues to the pathogenesis of this type of chondrosarcoma.

Adult↗
PubMed1994

Chromosome aberrations in fibrous dysplasia.

We report the cytogenetic findings of two cases of fibrous dysplasia, one occurring in the tibia, the other in the sphenoid. Both cases exhibited only one chromosome change: a t(6;11)(q15;p15) in the first case, a derivative chromosome 2 in the second. The previous cytogenetic report on fibrous dysplasia revealed only numerical changes. The significance of these inconsistent chromosomal findings in fibrous dysplasia is unclear.

Adult↗
PubMed1994

Cytogenetic characterization of tenosynovial giant cell tumors (nodular tenosynovitis).

Chromosome investigation in six localized forms of tenosynovial giant cell tumors, also known as modular tenosynovitis, revealed an identical translocation between chromosomes 1 and 2, t(1;2)(p11;q35-36) in three tumors, a variant translocation t(1;5)(p11;q22) in a fourth case, and a t(2;16)(q33;q24) in a fifth case. One case showed a normal karyotype. Although morphologically rather uniform, these benign tumors appear to be cytogenetically heterogeneous, but the chromosome changes seem to cluster in 2 regions, 1p11 and 16q24.

Adult↗
PubMed1994

Some desmoid tumors are characterized by trisomy 8.

Ten desmoid tumors were examined by chromosome banding analysis and by in situ hybridization on short-term cultures and frozen sections. Trisomy 8 was detected in four out of ten tumors, of which only one had shown trisomy 8 by karyotype analysis. Since trisomy 8 has been reported in superficial fibromatoses, which are clinically distinct but histologically similar to desmoid tumors, the occurrence of trisomy 8 in both may be a further indication of a close relationship.

Adolescent↗
PubMed1994

Clinical aspects of incomplete septal cirrhosis in comparison with macronodular cirrhosis.

BACKGROUND/AIMS: Incomplete septal cirrhosis (ISC) is a form of macronodular cirrhosis characterized by slender, incomplete septa that demarcate inconspicuous nodules. Its clinical features have not been investigated in a large series. The aims of this study were to review the clinical symptoms and evolution of ISC in 42 patients. METHODS: Forty-two patients with at least one liver biopsy strongly suggestive of ISC were selected for the study covering a period between 1968 and 1987. Data for these patients were compared with the evolution of 49 patients with classical macronodular cirrhosis after chronic active hepatitis type B or C. RESULTS: Possible etiological factors for ISC were alcohol abuse, arsenic treatment, and hepatitis B infection. In three cases, a genetic factor could not be excluded. Patients with ISC had significantly lower serum concentrations of transaminases and bilirubin at diagnosis. Compared with macronodular cirrhosis, bleeding varices were more frequent (57% vs. 22%) in ISC. Ten-year survivals in the ISC and the macronodular cirrhosis groups were 54% and 57%, respectively. CONCLUSIONS: ISC represents a relatively stable burnt-out form of macronodular cirrhosis with an unusually high incidence of variceal bleeding. This could be explained by a superimposed insufficiency of the portal vascular supply.

Adolescent↗
PubMed1994

New discriminative chromosomal marker in adipose tissue tumors. The chromosome 8q11-q13 region in lipoblastoma.

Specific chromosome abnormalities characterize benign and malignant adipose tissue tumors and are of great diagnostic and clinical importance. Lipoblastoma is a rare benign adipose tumor that mimics myxoid liposarcoma histologically. Although only a few lipoblastomas have been investigated cytogenetically, it is increasingly clear that these adipose tissue tumor generally show rearrangements of 8q11-q13 region but lack the t(12;16) that allows these tumors to be distinguished from myxoid liposarcomas.

Chromosomes, Human, Pair 8↗
PubMed1994

Three cases of non-tumoural tight stenosis of the bifurcation of the hilar bile ducts.

Stenosis of the bifurcation of the hepatic bile duct is usually caused by malignant lesion. We report on three different causes of benign stenosis of the hepatic confluence with a similar radiological pattern on direct cholangiography. The first case is considered a spontaneous neuroma, the second a periductal abscess, and the third case a postoperative stricture Bismuth type 4.

Adult↗
PubMed1994

Pulmonary histiocytosis X diagnosed by bone biopsy. Report of a case.

Histiocytosis X of the lung is associated with bone lesions in 4 to 20%. We report a case in which the diagnosis was missed in spite of repeated bronchoscopies with transbronchial lavage. The diagnosis was finally established by isotope bone scan, subsequent skeletal CT-scan and bone biopsy.

Adult↗
PubMed1994

Pleuropulmonary blastoma (pulmonary blastoma of childhood): genetic link with other embryonal malignancies?

A case of pleuropulmonary blastoma (childhood variant of pulmonary blastoma) was examined using histological, immunohistochemical, ultrastructural and cytogenetic methods. The tumour consisted of undifferentiated 'blastematous' areas admixed with zones of rhabdomyoblastic and chondroid differentiation and fascicular areas. Desmin and S-100 protein immunoreactivity confirmed the myogenic and cartilaginous differentiation. Ultrastructurally only undifferentiated mesenchymal cells were present. The cytogenetic analysis revealed abnormalities of 2q. Involvement of 2q has also been described in hepatoblastoma and embryonal rhabdomyosarcoma. Although further confirmation is needed, our cytogenetic findings in pleuropulmonary blastoma suggest common genetic mechanisms in some paediatric embryonal malignancies.

Biopsy↗
PubMed1994

Iron concentration and distribution in the newborn liver.

Recent observations on a correlation between fetal serum ferritin and gestational age, consistent with an increase in fetal iron stores during pregnancy, led us to study liver iron content in 22 human stillborns, newborns and infants of different gestational and postnatal age. At autopsy, a longitudinal liver slice was subdivided into ten blocks. Each sample was analyzed for iron content by atomic absorption spectroscopy. The mean iron concentration in the studied livers was 21.6 microM/g dry tissue (d.t.). A striking interindividual variability in iron content was observed: the hepatic concentration of the metal ranged from 3.3 to 64.4 microM/g d.t. No correlation was found between the hepatic iron concentration and gestational age or other clinical parameters of the patients studied. Moreover, the total storage iron of the liver did not appear to be correlated with the gestational age. The analysis of iron concentration in ten blocks in each liver revealed an irregular distribution of the metal. Lobar differences were observed, with a tendency of the left lobe to accumulate more iron than the right one. Furthermore, striking differences in iron content were found between adjacent liver samples, ranging in one instance from 4.5 up to 109.0 microM/g of dry tissue. Perls' stain for iron was positive in 7 out of the 22 livers examined, showing an irregular acinar distribution, with preferential periportal localization. Our data show that the newborn liver can be considered an interesting model for the study of iron storage.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗
PubMed1993

Cytogenetic and fluorescence in situ hybridization investigation of ring chromosomes characterizing a specific pathologic subgroup of adipose tissue tumors.

Cytogenetic analysis of 184 adipose tissue tumors, 175 lipomas, and nine liposarcomas (LPS) showed the presence of a ring chromosome and/or a long marker chromosome in 10 cases with common histologic features such as atypical stromal cells with or without lipoblasts. In five of the cases, this appeared to be the sole cytogenetic abnormality. Fluorescence in situ hybridization (FISH) analysis with a microclone library specific for chromosome region 12q13-q15 showed extensive staining of the ring and long marker chromosomes, indicating that genetic sequences of this particular region of chromosome 12 are present in these marker chromosomes, most likely in an amplified form.

Adipose Tissue↗