Biomedical subjects

R Kodet

Publications and source records attributed to R Kodet.

At least 73 records · Page 4Linked to original sources

PubMed1995

[DNA cytometry analysis in childhood tumors].

BACKGROUND: DNA contents in cells may be determined by flow cytometry. The relationship between malignant cell aneuploidy and prognosis is known in many types of neoplasms in adults and in children. In some situations, demonstration of an aneuploid clone verifies presence of malignant cells. Aneuploidy is rare in benign diseases. This report summarizes our first experiences with cytometric DNA analysis and shows the method's abilities to other potential users. METHODS AND RESULTS: We investigated DNA contents in blood and bone marrow (BM) specimens of 25 children with leukemia, in 41 unfixed solid tumors after biopsy and in 24 specimens of paraffin embedded neuroblastoma tissue. We also investigated 5 specimens of cerebrospinal fluid (CSF) of patients with medulloblastoma, 18 specimens of CSF from patients with leukemia or lymphoma, 4 pleural exudates suspected from malignancies, and 45 specimens of possibly infiltrated BM from primary solid tumors. As the purpose of this study was to test the method on a relatively small number of specimens, we did not perform statistical analysis of our data. As reported previously, aneuploidy was frequent in CALLA + acute lymphoblastic leukemia and in types of neuroblastoma with favorable prognosis (lower clinical stages and less than 2 years of age). CONCLUSIONS: Our results show that DNA ploidy may be tested by flow cytometry in an easy and fast way. The source of the material may be unfixed tumors, deparaffinized tumors, BM, blood, CSF and pleural exudates.

Adolescent↗

PubMed1995

Rectal adenocarcinoma with rhabdoid phenotype.

Tumour of the rectum was found in 50-year old man. Two different components were identified. The rectal wall was infiltrated by a tumour with rhabdoid phenotype which formed majority of tumour mass. This type of tumour grew under differentiated tubular and mucinous adenocarcinoma which was present in small extent. Ultrastructurally rhabdoid cells revealed clusters and whorls of intermediate filaments without myoblastic differentiation. Strong anti-vimentin positivity prevailed over the anti-cytokeratin positivity. The authors suggest that this is a case of an adenocarcinoma transforming into a poorly differentiated form with rhabdoid phenotype.

Adenocarcinoma↗

PubMed1994

Renal cell carcinoma in children: a single institution's experience.

Seven patients with renal cell carcinomas (RCC) were treated at the Department of Pediatric Oncology in Prague over a period of 15 years. The average age at diagnosis was 8 years 9 months. Histology review showed five tumors to be of clear cell type with mixed tubular, papillary, and solid patterns; one tumor was purely papillary eosinophilic type and one was composed of clear and eosinophilic cells. Five patients received chemotherapy and four of them also received radiotherapy. Four patients are without evidence of disease with a minimal follow-up period of 2 years. These four were all clinical stage I or II. Two stage III patients died of metastatic disease. One patient died of tumor emboli to the lungs at operation. Tumor diagnosis and treatment of the patients in the lower clinical stages seem to have a favorable prognostic impact in childhood RCC. Combined chemotherapy with vinblastine as one of the agents, and possibly additional immunotherapy, appears to have promising results, although the number of patients treated thus far is limited.

Adolescent↗

PubMed1994

Bone metastasizing renal tumor of childhood. A clinicopathological study of eleven cases from the Prague Pediatric Tumor Registry.

Eleven patients with bone metastasizing renal tumor of childhood (BMRTCh) who were diagnosed and treated in our departments over a 20-year period were reviewed. The incidence among all malignant renal tumors in children up to 15 years of age in our files was 3.7%. The male to female ratio was 10:1. The morphology had a uniform, predominantly clear cell finely vascularized pattern in all of them. Various previously recognized variations of the classic pattern such as hyalinization, nuclear palisading and cyst formation were observed in some patients. Electron microscopy showed that coarse vacuolization of the tumor seen at the light microscopic level was due to distended extracellular spaces surrounded by tumor cells and their cytoplasmic processes. Immunohistochemistry of the tumor cells revealed positive vimentin in all cases, and focally positive muscle specific actin in one. A prominent feature was fascicles of perivascular spindle cells. They were considered to be tumor cells rather than stromal elements since their morphology was close to the appearance of the polygonal tumor cells. The follow up data were available for ten patients. Four developed bone metastases, three of them died of the disease progression. Another patient died of lymph node dissemination and gastrointestinal bleeding. Six patients survived for a period of 29 months to 14 years following the diagnosis.

Bone Neoplasms↗

PubMed1994

Juxtaglomerular cell tumor. An immunohistochemical, electron-microscopic, and in situ hybridization study.

We present a case of juxtaglomerular cell tumor (JCT) in a 10-year-old boy. The child suffered from severe hypertension that returned to normal following the tumor resection. The diagnosis of JCT was supported by electron-microscopic findings of typical rhomboid secretory granules and by immunohistochemistry using a polyclonal antibody against active and inactive forms of renin. The production of renin by the tumor cells was confirmed by demonstration of specific renin mRNA by in situ hybridization (ISH). The immunohistochemistry also showed a weak positivity of renin in the media of interlobular arteries and in the epithelial cells of proximal tubules. The ISH was negative for renin mRNA at these sites, indicating that renin positivity was due to an uptake of renin rather than to renin production. The juxtaglomerular apparatuses in the adjacent renal cortex were negative for renin, suggesting a compensatory inhibition mechanism by the hyperreninemia. The tumor was encapsulated by a fibrous tissue, but the capsule was penetrated by clusters of the tumor cells--an indication of the tumor's invasive capability.

Adenocarcinoma↗

PubMed1994

[Surgical methods in the treatment of retroperitoneal neuroblastoma].

The authors submit their experience with the surgical treatment of retroperitoneal neuroblastoma, which is one of the most frequent solid tumours of child age. They describe the principles of the surgical technique with emphasis on radical removal of the tumour even in the area of large blood vessels. They emphasize the advantage of using an ultrasonic surgical aspirator (CUSA, Valleylab Co., Pfizer) which makes it possible to remove residues of the tumour without damaging the large blood vessels. During the period between 1987-1992 they treated at the Motol Faculty Hospital 69 children with retroperitoneal neuroblastoma. Of these 60 were operated. In the first stage of the disease 9 patients were operated, all survive. In the second stage 4 patients were operated, 75% survive, in the third stage 24 patients 50% survive, in the fourth stage 20 of 29 patients were operated and 11 (38%) survive. In stage IV--S three patients were operated, one survives. The total survival of patients during the investigation period is 52%.

Adolescent↗

PubMed1993

Childhood rhabdomyosarcoma with anaplastic (pleomorphic) features. A report of the Intergroup Rhabdomyosarcoma Study.

The pleomorphic subtype of rhabdomyosarcoma (RMS) is now rarely diagnosed in both children and adults. Most cases previously called pleomorphic RMS are probably diagnosed as something else, most often embryonal RMS in children and malignant fibrous histiocytoma in adults. To analyze the concept of pleomorphic RMS in children, we reviewed the tumors of patients entered on the Inter-group Rhabdomyosarcoma Study (IRS I, II, and III). The presence of cells with lobated, hyperchromatic nuclei at least three times larger than the common tumor cell population (anaplastic cells) was selected as the main criterion. Of about 3,000 cases, 110 showed these types of cells, had sufficient histologic material, and had available follow-up data. These tumors were divided into two subgroups: Subgroup I tumors contained only scattered anaplastic cells, and tumors with foci or large sheets of anaplastic cells were classified as subgroup II. Besides the anaplastic-pleomorphic areas, most of these tumors had distinctive features of embryonal RMS (105 cases) and rarely had characteristics of alveolar RMS (five cases). The age distribution of these patients did not differ significantly from those whose tumors did not show the anaplastic features, the average being 6 years and the median 4 years. Lower extremity, retroperitoneum, and the head and neck region were the most common primary tumor sites. The 5-year survival rate was 60% for subgroup I tumors and 45% for subgroup II tumors compared with the survival rate of 68% for 482 IRS II embryonal RMS cases with no anaplastic-pleomorphic features. The lower survival rate for patients in subgroup II was statistically significant (p = 0.004) and similar to the unfavorable survival of patients with alveolar RMS and undifferentiated sarcoma. Because anaplastic cells are seen in many soft tissue sarcomas and in both embryonal and alveolar RMS in children, this feature is not sufficiently unusual to separate a pleomorphic subtype of RMS. The presence of anaplastic cells in aggregates or diffuse sheets throughout the tumor, however, portends a poor survival for these patients.

Antibodies↗

PubMed1993

Infantile sialic acid storage disease (ISSD). Report on first case in Czech Republic with biopsy and autopsy findings.

The first case of infantile sialic acid storage disease in Czech Republic is presented in a four-and-half year-old girl. The clinical phenotype consisted of moderate hepatosplenomegaly and skin hypopigmentation, early psychomotoric and developmental arrest, associated with truncal ataxia and lower extremities spasticity, extinguished acoustic and visual perception (optic atrophy without macular alteration) and remarkable automutilation phenomena. The appearance was normosomatic and there were minimal dysostotic changes. Skin and liver biopsy displayed moderate amount of lucent storage lysosomes in epithelial, mesenchymal, and neural elements. Alder-Reily granules were found in the bone marrow and peripheral blood cells. The urinary excretion of mucopolysaccharides and oligosaccharides was not increased. The autopsy showed heterogenous neuronal and glial brain storage (lucent lysosomes, lipopigment, membranous cytoplasmic bodies), severe hypomyelination and severe storage in the splenic sinus endothelium. Diagnosis was made by proving thirteen fold increase of free sialic acid in the fibroblast culture. It is pointed out that in the case of a mucopolysaccharidosis-like storage disease unexplainable by a hydrolytic enzyme deficiency, it is the enzyme product storage which must be suspected. At present, the only candidate is the sialic acid storage disease.

Child, Preschool↗

PubMed1992

Fibrous hamartoma of infancy. A study of eight cases with immunohistochemical and electron microscopical findings.

Eight cases of fibrous hamartomas of infancy are presented. Actin positivity and desmin negativity in collagen forming spindle-shaped cells and electron microscopical findings point to the myofibroblastic nature of this entity. "Dark cells" which spread regularly in all but one of our tumors were immunohistochemically determined to be a mixture of B and T cell lymphocytes. Their selective location and possible role are discussed.

Actins↗

PubMed1992

[Flow cytometry in primary renal tumors in childhood].

A group of nineteen primary renal tumors in childhood was analyzed by flow-cytometry. All clinically important entities were included. Paraffin embedded material was used. Two anaplastic nephroblastomas and a case of renal rhabdomyosarcoma had an aneuploid DNA content. One Wilm's tumor showed a moderate DNA-hyperdiploidy. One of two rhabdoid tumors showed a marked right-sided shift of G1/G0 phase from that of a control and was considered as probably hyperdiploid. All other tumors including high grade neoplasms such as rhabdoid tumor and bone metastasizing tumors were found in the DNA-diploid range. Proliferation index was high in most tumors and in six it reached or exceeded 40. Mitotic index counted in the histological sections correlated with the percentage of G2 + M phase in most cases. Although small, the group of tumors under study shows that prognostic criteria cannot be based on the DNA content or on the proliferation index only. The only relevant result may be an overt DNA-aneuploidy in anaplastic nephroblastomas. Difficulties in interpreting the results of flow cytometry are discussed.

Child↗

PubMed1992

[Langerhans-cell histiocytosis in children].

Histiocytosis from Langerhans cells is a new term for a group of diseases formerly called histiocytosis X. In The Faculty Hospital Motol the authors treated between July 1974 and December 1980 84 children with this disease. Twenty one suffered from the malignant form (formerly Letterer-Siwe and Hand-Schüller-Christian disease) and in 63 patients the diagnosis of eosinophil granuloma was established. In 21 children with unequivocally malignant disease the authors started chemotherapy immediately after establishment of the diagnosis and in six they indicated in addition radiotherapy. Of these 21 children 16 are in complete remission and 5 children died from progression of the disease during treatment. In the group of 63 children with eosinophil granuloma in 44 only excochleation of the focus was performed. Chemotherapy was administered to 12 children, incl. 5 where it was combined with radiotherapy. A relapse of the disease was recorded in 8 children. At present all patients suffering from the disease are in complete remission.

Adolescent↗

PubMed1992

[Fibromatoses and related disorders in childhood].

A retrospective study of fibromatoses and related diseases was performed on a series of 34 children. Aggressive forms of fibromatoses similar to those in adults as well as typical forms of childhood fibromatoses and fibrous proliferations, such as sternocleidomastoid tumor, infantile myofibromatosis, digital fibromatosis and fibrous hamartoma were observed. Immunohistochemistry revealed muscle specific actin in eleven out of 13 cases, including hyaline cytoplasmic inclusions in digital fibromatosis. In two patients with infantile myofibromatosis a coexpression of actin and desmin was found. One of two cases of infantile type of aggressive fibromatosis was weakly actin positive whereas the other was negative. This result suggests poorly differentiated character of cells in infantile fibromatosis. Clinicopathologic correlation showed that extraabdominal fibromatoses had a strong propensity for local recurrence. Multiple lesions affecting different muscle groups were diagnosed in two boys. Abdominal fibromatosis affected two girls and two boys, in contrast to adult forms which occur exclusively in women.

Adolescent↗

PubMed1991

Is fetal cellular rhabdomyoma an entity or a differentiated rhabdomyosarcoma? A study of patients with rhabdomyoma of the tongue and sarcoma of the tongue enrolled in the intergroup rhabdomyosarcoma studies I, II, and III.

A tumor of the tongue with features consistent with the diagnosis of fetal cellular rhabdomyoma was seen in an 18-month-old infant. The tumor recurred 10 and 22 months after initial resection. The histologic condition of the first recurrence was similar to the original tumor except for some increased nuclear irregularities and mitotic activity. No adjunctive therapy was administered initially or after the first recurrence. The second recurrence showed mixed embryonal/alveolar rhabdomyosarcoma. This case represented a unique model of a highly differentiated striated muscle tumor converting to a moderately differentiated rhabdomyosarcoma, and illustrated differential diagnostic difficulties in distinguishing between fetal cellular rhabdomyoma and differentiated rhabdomyosarcoma. The patient was compared with eight children and adolescents with primary sarcomas of the tongue who entered the Intergroup Rhabdomyosarcoma Studies (IRS) I, II, and III protocols. The tumors of all eight arose at the base of the tongue. There were five embryonal, one alveolar, and one mixed embryonal/alveolar rhabdomyosarcomas, and one undifferentiated myxoid sarcoma. Five rhabdomyosarcomas were poorly differentiated, and two had a moderate degree of myogenesis. These sarcomas of the tongue represent approximately 0.34% of all cases entered in IRS studies.

Biopsy↗

PubMed1991

Rhabdoid tumors of soft tissues: a clinicopathologic study of 26 cases enrolled on the Intergroup Rhabdomyosarcoma Study.

Twenty-six cases of malignant soft tissue tumors with features similar to renal rhabdoid tumors were identified among approximately 3,000 childhood sarcomas entered on Intergroup Rhabdomyosarcoma Studies I-III. The tumors consisted of polygonal cells with vesicular nuclei and prominent nucleoli and cytoplasmic intermediate filament inclusions as identified by electron microscopy and immunohistochemistry. The growth pattern was predominantly solid or solid-trabecular. Immunohistochemistry showed vimentin, wide spectrum keratin, and epithelial membrane antigen to be the most consistent antigenic phenotypes. Eleven patients were infants less than 1 year of age. The tumors affected predominantly soft tissues of proximal extremities, trunk, and retroperitoneum/pelvis/abdomen. Nineteen patients died within 1 to 82 months (median, 6 months) from the start of treatment. Five patients have survived the disease for 2 to 13 years. When compared with the survival analysis of 991 Intergroup Rhabdomyosarcoma Study II patients, it was obvious that this group of tumors fares very poorly (P less than .001). The tumor belongs to the group of soft tissue neoplasms showing mesenchymal and subtle epithelial differentiation, similar to epithelioid sarcoma. Because of its identifiable histology, site and age distribution, and poor outcome, it warrants a status as an independent entity.

Adolescent↗

PubMed1991

Congenital histiocytosis. A heterogeneous group of diseases, one presenting as so-called congenital self-healing histiocytosis.

Three cases of congenital histiocytic disorders--generalized Langerhans cell histiocytosis, generalized juvenile xanthogranuloma and so-called congenital self-healing histiocytosis are compared using histiochemical, immunohistochemical and ultrastructural methods. The results showed a typical morphological pattern of Langerhans cell histiocytosis (S 100+, CD 1+, alpha-mannosidase +) with an unusual self-healing cutaneous phenomenon. The congenital self-healing histiocytosis showed a non-Langerhans cell immunophenotype (CD 14+, CD 1-, S 100-) and morphological appearance resembling the evolutive "early" stage of juvenile xanthogranuloma. A diffuse cellular positivity of alpha-mannosidase in juvenile xanthogranuloma and congenital self-healing histiocytosis differed from a typical perinuclear globular positivity of this enzyme in Langerhans cell histiocytosis. It is concluded that congenital self-healing histiocytosis may in some cases be of non-Langerhans cell type and under this term a clinically characteristic syndrome of histiocytic proliferation of Langerhans cells or tissue histiocytes may be included.

Biomarkers↗

PubMed1991

Rhabdomyosarcomas with intermediate-filament inclusions and features of rhabdoid tumors. Light microscopic and immunohistochemical study.

A group of 27 rhabdomyosarcomas (RMS) whose histology showed abundant cells containing cytoplasmic intermediate-filament globular inclusions resembling those seen in rhabdoid tumors has been identified among Inter-group Rhabdomyosarcoma Study (IRS) I-III patients (less than 1%). Their histologic subtype was embryonal RMS in 22 and alveolar RMS in 5. One-half of tumors occurred in deep muscles of the extremities, retroperitoneum, or in the pelvis. Immunohistochemical analysis of 12 cases showed the inclusions to be vimentin or desmin positive. Anti-muscle-specific actin antibodies were positive in the cytoplasm of 11 cases, but not in the site of the intermediate-filament inclusions. Seven poorly differentiated neoplasms closely resembled rhabdoid tumors and possessed large nucleoli in most cells along with cytoplasmic inclusions. In contrast to true rhabdoid tumors, their nuclear chromatin was usually coarse. Immunohistochemistry proved useful in distinguishing tumors with early myoblastic differentiation. A positive anti-desmin, when confined to the cytoplasmic inclusions only, should be complemented with other muscle-specific antibodies, especially anti-muscle actin to separate RMS from rhabdoid tumors. The statistical analysis was limited by the small number of cases, but there was no statistical difference in survival when this group of RMS was compared with 996 IRS-II patients as a whole. The distinction of RMS with abundant intermediate-filament inclusions from rhabdoid tumors is of clinical importance because patients with true rhabdoid tumors have a highly unfavorable prognosis.

Humans↗

PubMed1991

[Tumors of the peripheral sympathetic nervous system in childhood. Immunohistochemical study].

Twenty tumors of the peripheral sympathetic nervous system were investigated using a spectrum of antibodies against vimentin, neurofilament triplet, S-100 protein, neuronal specific enolase (NSE), chromogranin, synaptophysin, and vasoactive intestinal polypeptide. There were two ganglioneuromas, seven stroma rich neuroblastomas (composite ganglioneuroblastomas), five undifferentiated and six differentiating stroma poor neuroblastomas (NB) included in the series. Formalin-fixed, paraffin embedded material was used. The results showed that reactivity of the antibodies was relatively high, except the reactivity against synaptophysin. The tumor cell population showed a heterogeneous positivity in all cases. Only some undifferentiated NB were positive with the employed antibodies, which reduces the diagnostic benefit in a group of NB in which diagnostic demands of the immunohistochemistry are most important. The best results in undifferentiated NB were obtained with polyclonal antibody against NSE. This antibody is, however, not specific. Positive results of the immunohistochemistry in this group of tumors should be evaluated with caution.

Child↗

PubMed1990

Antibody against synthetic peptide derived from Epstein-Barr virus-determined nuclear antigen 1 (EBNA-1) in child non-Hodgkin's lymphoma.

Antibody reactivity against a synthetic peptide derived from Epstein-Barr virus nuclear antigen 1 (EBNA-1) was determined in 56 cases of child non-Hodgkin's lymphoma and 31 controls. The patients were divided into subgroups based on tumour location and histology and the antibody responses in the various groups were compared. A significant increase in both IgG and IgM antipeptide titres was detected in patients with tumours localized in the abdomen. High IgG titres were also noted in Burkitt-type, lymphoblastic, and centroblastic lymphomas. On the other hand, low or nil IgG titres were found in unclassified malignant lymphomas, in four cases of centroblastic-centrocytic lymphoma and in lymphomas located in the mediastinum. Surprisingly, the occurrence of antipeptide IgM antibody was highest in those tumours, where IgG titres were low, i.e. in subjects with mediastinal tumours and in unclassified malignant lymphomas. However, with the exception of tumours localized in the abdomen and unclassified tumours, the IgM titres in positive individuals were low and comparable with titres found in a part of healthy controls.

Abdominal Neoplasms↗