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Biomedical subjects

J Hassoun

Publications and source records attributed to J Hassoun.

At least 91 records · Page 5Linked to original sources
PubMed1990

Detection of five different human papillomavirus types in cervical lesions by in situ hybridization. A study of 110 cases using sulfonated probes.

Several findings suggest an etiologic relationship between genital tract squamous cell carcinoma and certain types of human papillomavirus (HPV). Detection of these HPV types in cervical lesions considered as preneoplastic states (ie, cervical intraepithelial neoplasia or CIN) is extremely important but difficult because the morphology of these states is highly heterogeneous and clinical course is rarely predictable. In situ hybridization (ISH) is the only technique allowing correlation between HPV type and tissue or cell morphology. In this report, 110 biopsy specimens from uterine cervix lesions were studied: 66 CIN, 10 invasive carcinoma, 28 metaplasia, and six condyloma acuminata. A new ISH technique based on direct modification of DNA probes by sulfonation was used. The hybridized DNA was revealed first by a specific monoclonal antibody against sulfonated DNA, and then by an alkaline phosphatase system. In order to determine the sensitivity level of this method, 14 biopsy specimens were also submitted to Southern blot hybridization. Five probes were used separately (HPV 6, 11, 16, 18, and 33) for each biopsy specimen. Results of ISH were correlated with morphologic criteria such as number of koilocytes and mitoses. Oncogenic HPV was found exclusively in CIN. The number of labeled cells varied with CIN grade. These data suggest that, whatever the grade, CIN represents a unique preneoplastic process, and that HPV replication depends on the squamous maturation of the pathologic epithelium.

Blotting, Southern↗
PubMed1990

What's new in primary central nervous system lymphomas?

Primary central nervous system lymphomas (CNSL) are uncommon neoplasms accounting for about 1% of primary brain tumors. Patients with congenital or acquired immunodeficiencies including AIDS patients and transplant recipients represent the main high-risk population for CNSL occurrence. An important point emerging from the literature is that CNSL incidence has dramatically increased during the last years not only in HIV infected patients by virtue of the AIDS epidemic spread, but also for unclear reasons in immunologically normal persons. Although c-myc oncogene activation and Epstein-Barr virus infection are considered to play a role in CNSL development, the peculiar tendency of these lymphomas to occur and remain inside the CNS is not well understood and may involve putative CNS binding molecules carried by lymphocytes. The clinical presentation is characterized by a great variety of neurological disorders. Radiological features consist of hyperdense homogeneous deposits within the subcortical white matter with a pattern of marked enhancement after injection of contrast material. The tumor masses are usually ill-defined and multicentric. Although all cytological types can be observed, the most common types belong to the high-grade category of non-Hodgkin's lymphoma. Monoclonal antibodies reactive with formalin-fixed, paraffin-embedded sections can be used in conjunction with stereotactic needle biopsy to provide accurate immunological characterization of CNSL. The large majority of CNSL is of B-cell origin but T-cell lymphomas seem at the present time less exceptional than previously thought. Although radiotherapy and chemotherapy can increase length of survival, the prognosis of CNS remains dramatically poor, the shortest survival being observed in AIDS patients.

Humans↗
PubMed1990

Genotypic analysis in large cell lymphomas expressing a restricted set of differentiation antigens.

Immunophenotyping and immunogenotyping were performed in a series of 8 large cell lymphomas exhibiting anaplastic or "histiocytic" morphology and displaying an uncertain phenotype due to a restricted number of differentiation antigens. 6 cases expressed the Ki-1 antigen. 4 cases expressed one or two B-cell markers and contained rearrangements of the immunoglobulin genes. One of them also exhibited a T-cell receptor (TCR) beta gene rearrangement. 3 cases expressed a single T-cell differentiation antigen. Among them, only 1 displayed both gamma and beta TCR gene rearrangement; 1 only contained a gamma TCR gene rearrangement and 1 completely lacked clonal rearrangements. The eight cases expressed an inconclusive immunophenotype due to an abundant population of reactive cells but showed an immunoglobulin gene rearrangement. In conclusion, 5 out of the 8 unusual lymphomas studied here could be characterized by immunogenotyping. This approach was, however, inconclusive in the 3 remaining cases, whose lineage and differentiation stage remain poorly defined.

Adult↗
PubMed1990

Rearrangement of the beta T-cell receptor gene in a monocytoid B-cell lymphoma.

We describe an unusual case of monocytoid lymphoma displaying a rearrangement of the T-cell receptor beta-chain gene associated with a rearrangement of the immunoglobulin heavy-chain gene, and of the lambda light-chain gene. This lymphoma was morphologically similar to previous cases in the literature, and was clinically of low grade. The lymphoma expressed the lambda light chain, HLA-DR, CD21, and CD22. Though the B-cell lineage of this lymphoma seems very likely, the genotypic profile raises a cautionary note regarding the supposed high stage of differentiation of monocytoid lymphomas.

B-Lymphocytes↗
PubMed1990

[Comparative study of fine needle aspiration and large caliber needle biopsy under echographic control for the diagnosis of abdominal tumors].

The aim of this study was to compare the results of fine needle aspiration (22 G) with large caliber needle biopsy (18 G) in patients suspected of having abdominal malignancy. From November 1988 to December 1989, 73 patients aged 32 to 78 years (mean 66 years), suspected sonographically of having hepatic malignancy (66 cases) or extrahepatic tumors (7 cases), underwent ultrasonography guided percutaneous fine needle aspiration (22 G) and biopsy with a large caliber needle (18 G). There were no complications. Overall sensitivity for diagnosis of malignancy was significantly better (p less than 0.01) with 18 G needle biopsies (91.2 percent) than with fine needle cytology (71.4 percent). Specificity was 100 percent. The distinction between primary and secondary malignant tumor was possible in 87.5 percent with the large caliber needle and in only 42.9 percent with the fine needle (p less than 0.001). Histological findings were adequate hepatic metastases in 86.5 percent with the 18 gauge needle and in 51.4 percent with the 22 gauge needle (p less than 0.001). In the 7 extra-hepatic tumors, the 18 G biopsy was always positive whereas fine needle cytology was positive in only 5 out of 7 cases. Correct diagnosis for benign diseases was possible in 7 out of 10 cases with the large caliber needle whereas the fine needle cytology was always negative. These results show the superiority of large caliber needle (18 G) compared to fine needle (22 G) guided punction for both diagnosis of malignancy and origin of the tumor. Complications did not occur more frequently than with fine caliber needles.

Adult↗
PubMed1990

[Contribution of the analysis of genotype to the diagnosis of malignant lymphoma with abundant epithelioid reaction. Apropos of a case].

The authors describe the case of a 67 year-old woman bearing a malignant lymphoma displaying two different histological patterns: a Lennert's lymphoma pattern in a cervical lymph node and a diffuse centroblastic lymphoma pattern in an axillary node. Immunophenotyping on frozen and paraffin sections showed a predominant positivity of T-cell markers in the cervical node, while the axillary lymphadenopathy exhibited a major positivity of B-cell markers and a restricted expression of the lambda light chain. However, genotyping provided the evidence of a single neoplastic B-cell clone proliferating in both cervical and axillary nodes. These findings suggest that histological pattern of Lennert's lymphoma is devoid of absolute specificity. Thus, genotypic analysis is a useful tool for the diagnosis of so-called "lymphoepithelioid lymphomas".

Aged↗
PubMed1989

An exceptional 18-year follow-up after cardiac transplantation. How can malignancies occur during immunosuppressive therapy?

The present report considers the autopsic study of an homograft recipient who had been living for 18.5 years after a cardiac transplantation. The patient was treated by immunosuppressive therapy associating azathioprine and steroids. During the exceptionally long follow-up, two skin carcinomas and a lung carcinoma occurred successively. In addition, the autopsy allowed observation of a kidney adenocarcinoma associated to a polycystic disease, and a liver regenerative nodular hyperplasia containing several areas of severe dysplasia. These findings, when compared with those usually observed in immunodeficient patients, suggested the possibility that long-term immunosuppressive therapy may give rise to malignancies other than those arising after a short therapy.

Adenocarcinoma, Papillary↗
PubMed1989

[Clinically impalpable mammary carcinoma: morphologic and histogenetic analysis. Apropos of 114 cases].

In a population of 2,372 consecutive cases of breast carcinomas, 114 cases of clinically occult non palpable breast lesions have been diagnosed (4.8%). 51% of them can be considered as minimal breast carcinomas (MBC) by Gallager's definition and 72% by that of the American College of Surgeons; whatever the definition this category has an excellent prognosis with 11% of axillary invasion for the infiltrating tumors under 5 mm and 7% for these under 10 mm and 100% 5-year survival rate in both cases. The category of infiltrating tumors of over 5 mm and 10 mm also has a good prognosis with 21% and 26% of axillary lymph node invasion respectively, with a survival rate of 83.82% and 77.92%. The comparative histological analysis shows at this stage an increase in the intraductal carcinomas (IC) (35% instead of 6% for the palpable carcinomas), the infiltrating ductal carcinomas with predominant intraductal component (IDCPIC) (19% instead of 12%) and the tubular carcinomas (11% instead of 3%). The study of the peritumoral and environmental mastopathy and the histological repartition, confirms the classical histogenetic arguments regarding breast carcinomas.

Adenocarcinoma↗
PubMed1988

Specific tissue targeting of polyoma virus oncogenicity in athymic nude mice.

Inbred athymic nu/nu mice (BALB/c and C57BL/6) were injected subcutaneously with polyoma virus A2 strain or with polyoma mutants which are able to infect undifferentiated embryonal carcinoma cells and harbor mutations in their enhancer sequences. Mammary adenocarcinomas were induced exclusively in females in which they represent the majority of the tumors. Both males and females developed sarcomas, mostly osteosarcomas, with a similar low frequency. No other type of neoplasm was observed. Mutations affecting the enhancers do not have any effect on the histotype of the tumors. Multiple copies of intact or defective free viral DNA were detected in all tumors. Such a sex-linked specific tissue targeting suggests a hormonal control of tumor initiation and/or promotion. From a pathological point of view, polyoma-induced adenocarcinomas are very similar to human early breast cancers. Tumor induction in nude mice by polyoma virus therefore represents a unique experimental model which differs from the more extensively used newborn immunocompetent mice.

Animals↗
PubMed1988

[Hyperplasia of antral "G" cells. Quantitative evaluation in endoscopic biopsies].

The number of gastrin cells (G cells) and somatostatin cells (D cells) per surface unit, and the G/D cell ratio were estimated in biopsy specimens of the antrum from normal subjects without hypergastrinemia, and from patients with hypergastrinemia not induced by gastrinoma or supra selective vagotomy. Compared with normal subjects, antral G cell density and G/D cell ratio were significantly increased in patients with hypergastrinemia. A significant correlation was found between G cell density or G/D cell ratio and the integrated gastrin output values. A quantitative estimation appears therefore possible in biopsy specimens.

Adolescent↗
PubMed1988

Non lymphoblastic T cell lymphomas with prevalent skin involvement different from mycosis fungoides or Sézary's syndrome. A retrospective study of 6 cases in Europe.

A retrospective study of 23 cases of nonlymphoblastic T cell lymphomas with no features of either mycosis fungoides (MF) or Sézary syndrome (SS) was carried out. 6 patients exhibited cutaneous (or mucous) lesions and are presented herein. There was no detectable visceral or node involvement except in 1 patient. 3 cases were immunologically proven to be of peripheral T cell origin. Except T cell lymphomas in Japan and in the Caribbean area, the frequency of prevalent skin involvement is reportedly very low in non-MF/SS non lymphoblastic T cell lymphomas. However, it is likely that this frequency has been underestimated in Western countries. The histologic features of our cases run the heterogeneous spectrum of recently described node-based forms of peripheral T cell lymphomas: 'angioimmunoblastic lymphadenopathy with dysproteinemia'-like lymphoma, large T cell lymphoma, multilobulated cell lymphoma, T zone lymphoma. The histologic pattern of skin infiltration was different from that of MF/SS. One case was initially suggestive of a pseudolymphoma and had a prolonged evolution but the other patients suffered from rapid extracutaneous involvement and fatal evolution with resistance to treatment. Cutaneous plasmacytomas were seen in 1 case. Hence, certain cutaneous T cell lymphomas exhibit histologic, immunological and developmental features similar to those of node-based peripheral T cell lymphomas but different from those of MF/SS.

Aged↗
PubMed1987

Characterization of monoclonal antibodies against human thyrotropin and use in an immunoradiometric assay and immunohistochemistry.

Monoclonal antibodies were prepared against human thyrotropin. 13 different antibodies were characterized. Ten antibodies were of the IgG1 subclass. The affinities of the antibodies were in the range 10(9)-10(11) mol-1 X l. Four of them were specific for hTSH and did not react with hLH, hFSH, hCG or alpha hCG. Four reacted with these hormones and recognized the alpha subunit of hCG. One cross-reacted only with hFSH. The remaining four antibodies recognized the holo-hTSH only, and thus were designated as anti-conformational determinants. Monoclonal antibodies reacting with different antigenic determinants on the hTSH molecule defined seven clusters. Two of them were used to develop a simplified two-site sandwich radioimmunoassay in which one monoclonal antibody was immobilized on tubes (anti-beta TSH) and another (anti-alpha) labelled with 125I. This assay was highly specific and demonstrated a sensitivity level of 0.1 microIU/ml. Two monoclonal antibodies were used in immunohistochemistry and their quality and specificity was assessed in the detection of hTSH immunoreactivity in human pituitary biological sections.

Antibodies, Monoclonal↗