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R Kodet

Publications and source records attributed to R Kodet.

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

[Possibilities of diagnostic imaging in nephroblastomatosis].

Nephroblastomatosis means persisting embryonic, undifferentiated cells of renal blastoma which may give rise to a nephroblastoma. The foci of nephroblastomatosis create intrarenal nodi or a subcapsular border. The present scanning methods make it possible to correctly differentiate nephroblastomatosis in most cases and to differentiate it from most lesions previously hard to recognize from each other, while CT and arteriography represent the most sensitive methods. The main problem of differential diagnosis is still to differentiate nephroblastomatosis from nephroblastoma. For solving this problem it is frequently necessary to use more diagnostic methods including invasive arteriography and biopsy. It is the only way to prevent damage of the child by incorrect and most by too radical therapy. For the danger of the development of nephroblastoma even after regression of nephroblastomatosis in the X-ray picture a long-term observation is necessary, the ultrasound examination being the method of choice.

Angiography↗
PubMed1990

[Nephroblastomatosis and its relation to Wilms' tumor].

A group of 18 cases of nephroblastomatosis (NBM) was separated during an analysis of 188 renal tumours in childhood. NBM occurred associated with only Wilms' tumours (total 171 cases). NBM was classified according to a scheme of the "National Wilms' Tumor Study". Perilobar form was found in 5 cases, intralobar in 9, combined in 4 cases. Median age of all the patients suffering from NBM was close to that of the whole group of Wilms' tumours (37.4 months compared with 44.3 months). Medium age in the time of diagnosis of nephroblastoma with intralobar nephroblastomatosis was 28.3 months, i.e. by 16 months lower than the whole group of Wilms' tumours. The most frequent form of NBM consisted of mature tubular hamartomas or looked like renal basophilic adenomas. A blastemic component was less frequent and, in intralobar NBM, could not be distinguished reliably from blastemic structures in nephroblastoma. NBM could be distinguished even in necrotic tumours irradiated before the operation. NBM occurred in 5 of 8 bilateral nephroblastomas and in majority of primary multinodular tumours (63 percent). Relation of NBM to the development of Wilms' tumour is close but its value for pathogenesis cannot be proved unequivocally by morphology. Considering a high rate of bilateral NBM its finding in a kidney with Wilms' tumour necessitates regular checking of opposite kidney for early development of metachronic bilateral nephroblastoma.

Child, Preschool↗
PubMed1990

[Malignant lymphoma of the Burkitt type. Study of 21 cases in childhood].

From a group of 151 malignant lymphomas in childhood the authors selected 21 cases of malignant Burkitt lymphoma. The histopathological diagnosis was checked using common paraffin material, and a basic clinicopathological correlations was made. Malignant lymphoma of the Burkitt type was characterized by a diffuse type of growth with striking cellular cohesion. From the cytological aspect it was uniform with minimal differences in cell size. The presence of macrophages forming a "starry-sky" phenomenon was constant in the bioptic material. It is, however, not specific for Burkitt's lymphoma. In necroptic material macrophages were often absent and the morphology of tumour cells was altered. In the differential diagnosis it is necessary to differentiate in particular malignant lymphoblastic lymphomas and monomorphous centroblastomas. The malignant of Burkitt lymphoma type was localized in the majority of patients in the abdominal cavity, less frequently on the neck and in Waldeyer's ring. The mediastinum was not primarily affected. Five patients survive for 16-52 months after termination of oncological therapy without a relapse. Twelve patients died from generalization of the process, or from complications. Eight of those who died had a primary tumour in the abdominal cavity. The mean interval between the bioptic diagnosis and death was 3.6 months. As to the primary localization of the tumour and some other clinical and pathological data, various authors differ--these differences are discussed in relation to possible variations in the distribution of the tumour under different geographical conditions.

Burkitt Lymphoma↗
PubMed1989

Twin-glomeruli and duplication of glomerular capillary tuft in human kidneys.

Since the turn of this century the term twin-glomeruli (TG) designates a pair of glomerular capillary tufts supplied by a single afferent arteriole. Screening for TG has been performed in a series of kidney slides from 200 unselected consecutive autopsy cases with 21 (10.5%) positive results. Serial sectioning of 21 TG-positive and 10-TG-negative kidneys revealed the frequency of TG = 0.48% (71 among 15035 glomeruli) in the first group and 0.38% (32 TG among 8241 glomeruli) in the second. In individual cases the frequency ranged from zero up to 1.73% of all glomeruli. Three types of TG could be distinguished according to the distance between glomerular hili and the degree of Bowman's capsules coalescence. A complicated spatial relationship between the glomerular vessels and surrounding tubules was demonstrated by plastic reconstructions. TG are believed to be of a variety of renal architecture probably occurring in every human kidney. On the other hand, the glomeruli with two, mostly incomplete capillary tufts, which are occasionally found in the kidneys of newborns and children with multiple malformation syndromes and kidney dysplasias, are supposed to give evidence of a disturbed development of the kidneys.

Arterioles↗
PubMed1989

Rhabdomyosarcoma in childhood. An immunohistological analysis with myoglobin, desmin and vimentin.

A retrospective immunohistological analysis of 64 rhabdomyosarcomas in children was performed using antibodies against desmin and in 35 cases against myoglobin. In addition a group of 12 undifferentiated tumours in which the differential diagnosis included rhabdomyosarcomas was studied. Rhabdomyosarcomas were desmin positive in 57 cases (89%), 28 cases of which showed positivity of undifferentiated small cells (44%). Myoglobin was positive in 23 cases (66%), but only one case showed positivity of undifferentiated small cells. The results show the limited use of myoglobin in the diagnosis of rhabdomyosarcoma, especially of cases with a low degree of differentiation. Three out of 12 undifferentiated tumours were desmin positive and were reclassified as rhabdomyosarcomas. In 49 rhabdomyosarcomas the investigation was complemented by the demonstration of vimentin. Vimentin was shown to be present in 27 cases in tumour cells (55%). Undifferentiated cells were positive in 26 tumours (53%) and rhabdomyoblasts reacted in 9 cases (18%). Coexpression of vimentin and desmin in some cases reflects a situation in rhabdomyosarcomas that aberrantly mimics skeletal muscle embryogenesis. In three cases desmin and vimentin positive globular inclusions were observed. It is suggested that their formation is related to dystrophic changes of contractile and cytoskeletal filaments. From the diagnostic point of view a high percentage of desmin positive cases makes desmin a successful marker for rhabdomyoblastic tumours. It is pointed out, however, that even immunohistochemistry may not contribute to solving the problem of undifferentiated tumours and that each case must be evaluated comprehensively.

Child↗
PubMed1988

Epstein-Barr virus (EBV) antibodies in children with non-Hodgkin's lymphomas.

Antibody titres against Epstein-Barr virus (EBV) antigens in children suffering from non-Hodgkin's lymphoma (NHL) were determined. IgG antibody titres against the viral capsid antigen (VCA) and early antigen (EA) exceeded those found in healthy control subjects. On the other hand, antibody titres against EBV-determined nuclear antigen (EBNA complex) were generally lower than in the control group. The most striking phenomenon observed in the patient group was the frequent activation of latent virus infection as revealed by the periodical appearance of anti-EA and IgM class anti-VCA antibodies. Antibody titres against EBV antigens were generally lower among patients with progressing disease than in those with a more favourable course of the illness. The closest relation to EBV based on serological findings, was detected in lymphoblastic lymphomas of Burkitt-type histology, poorly differentiated lymphocytic lymphomas, and in lymphomas localized in the abdomen. The question whether EBV might be involved in a certain proportion of the cases examined is discussed and further approaches to elucidate this problem are suggested.

Adolescent↗
PubMed1986

Gangliorhabdomyosarcoma: a histopathological and immunohistochemical study of three cases.

A histopathological and immunoperoxidase study on three cases of genitourinary gangliorhabdomyosarcoma using a spectrum of conventional staining methods and antibodies against myoglobin, neuron-specific enolase and S-100 protein is presented. The results of the study have shown that differentiated myoblasts, ganglion cells and Schwann cells reacted positively with the particular antisera, but the majority of undifferentiated cells were negative. From the immunopathology results it was not possible to determine whether the undifferentiated cells were precursors of neural cells or myoblasts; the histological appearance resembled that of mesenchymal cells commonly seen in rhabdomyosarcomas. Theories concerning the origin of these tumours from neural crest ectomesenchyme or from neural crest and somitic mesenchyme are considered. Further study is needed to establish their histogenesis.

Cell Nucleus↗
PubMed1985

Papillary Wilms' tumour with carcinoma-like foci and renal cell carcinoma in childhood.

Five cases of Wilms' tumour with prominent papillary formation and focal carcinoma-like epithelium are described. The morphology of these tumours is compared with a group of six renal cell carcinomas in childhood. A link between this type of nephroblastoma and renal carcinoma is suggested but pure renal carcinomas are considered to be a separate category. The biological behaviour of the papillary Wilms' tumours was found to be more aggressive than is generally believed. The course of the disease may be influenced by carcinoma-like structures although this fact is not definitely established. Staging seems to be more helpful in such patients as is the case with renal cell carcinomas. Further studies on this type of Wilms' tumour are needed to establish more consistent data.

Carcinoma, Renal Cell↗
PubMed1985

Mesoblastic nephroma contains fibronectin but lacks laminin.

Non-metastatic mesoblastic nephromas from four young children were shown to contain fibronectin but not laminin using an immunoperoxidase staining procedure. In contrast, one metastasising spindle celled sarcomatous tumour from a neonate was laminin positive. During embryogenesis primitive nephrogenic mesenchyme contains only fibronectin and no laminin; metanephric blastema (permanent kidney) is positive for laminin. The staining for fibronectin and laminin may help to ascertain the histogenesis of different types of renal tumour.

Female↗
PubMed1985

[Rhabdomyosarcoma in childhood. I. Histologic structure].

Histological structure of rhabdomyosarcoma was studied in a group of 37 children. The classification was: embryonal rhabdomyosarcoma in 28 cases, alveolar rhabdomyosarcoma in 9 cases. 5 cases showed an ambivalent structure. The diagnosis of rhabdomyosarcoma is based on cytology: various rhabdomyoblasts are to be identified as well as distinguished from similar cells. The structural point of view is helpful but diagnostic only in typical cases of sarcoma botryoides and alveolar rhabdomyosarcoma. Undifferentiated cells maturating into rhabdomyoblasts combined with numerous polymorphic cells were found consecutive investigations of individual cases.

Adolescent↗
PubMed1985

[Rhabdomyosarcoma in childhood. II. Ultrastructure].

The diagnosis of rhabdomyosarcoma was established or proved by electron microscopy in two thirds of 21 cases. Histological classification was not adequate or formulated as "undifferentiated sarcoma" in half the cases. Electron microscopy did not succeed in one third of cases and rhabdomyosarcoma was classified according to simultaneous or successive study. Undifferentiated tumour cells resembled myoblastema cells of the 5th-6th gestation weeks. Differentiation of myoblasts and myotubes corresponded to the muscle development of the 7th-16th weeks. Immature cells showed features of fibroblasts and myofibroblasts in most cases of embryonal rhabdomyosarcoma. Alveolar rhabdomyosarcomas were characterized by exclusive myoblastic differentiation. Different cellular sources were discussed in rhabdomyosarcomas with differentiation into one cell type or into various mesenchymal cells.

Child↗