Giant cell collagenoma: a benign dermal tumor with distinctive multinucleate cells

We present five cases of a hitherto unreported cutaneous neoplasm. The tumors appeared as solitary slow-growing flesh-colored nodules arising in young and middle-aged adults. They were located on the trunk, the upper extremities, and the face, and did not recur after complete excision. Clinically, they were diagnosed as dermal nevus, Spitz's nevus, fibroma, or neurofibroma. Histology revealed polypoid flat-dome-shaped lesions with a sharply demarcated matrix consisting of coarse hyalinized collagen bundles arranged in a prominent storiform pattern and separated by mucin-containing clefts. Despite a low overall cellularity, the tumors contained numerous, occasionally bizarre-shaped, multinucleate giant cells with crowded vesicular nuclei and a pale staining foamy cytoplasm, as well as plump fibroblastlike cells with analogous nuclear morphology. Atypical nuclei or mitotic figures were not observed. The cells were strongly positive for vimentin but negative for cytokeratin, smooth muscle actin, desmin, S-100 protein, CD34, factor XIIIa, and the macrophage markers KP1, Mac 387, and Ki-M1p, suggesting a fibroblastic origin. Based on the overall architecture, we conclude that these tumors probably represent a distinctive variant of solitary circumscribed storiform collagenoma (sclerotic fibroma) and propose the designation of giant cell collagenoma.

Novel WT1 mutation, 11p LOH, and t(7;12) (p22;q22) chromosomal translocation identified in a Wilms' tumor case

About 5-10% of sporadic Wilms' tumors (WT) are associated with mutations in the Wilms' tumor 1 gene (WT1). More than 90% of patients with Denys-Drash syndrome (DDS; characterized by renal nephropathy, gonadal anomaly, and predisposition to WT) show constitutional intragenic WT1 mutations. We describe a novel WT1 stop-mutation in exon 2. This heterozygous germline mutation was detected in a one-year-old girl who was bilaterally affected with Wilms' tumor but without any other clinical manifestations of DDS. The C-to-A transversion is predicted to result in a polypeptide comprising only the first 165 amino acids of the WT1 protein. Loss of heterozygosity (LOH) studies comparing tumor DNA with lymphocyte DNA revealed LOH for the entire short arm of chromosome 11 in tumor tissue. In addition to the chromosome 11 lesions, the tumor showed a seemingly balanced chromosomal translocation t(7;12) (p22;q22) as the only visible cytogenetic aberration.

TEL-AML1 fusion transcript in relapsed childhood acute lymphoblastic leukemia. The Berlin-Frankfurt-Münster Study Group

The cryptic translocation t(12;21)(p13;q22) has been recently recognized as the most common genetic rearrangement in B-lineage childhood acute lymphoblastic leukemia (ALL). The resulting fusion transcript, termed TEL-AML1, has been associated with an excellent prognosis at initial ALL diagnosis. Hence, we postulated that the incidence of TEL-AML1 fusion should be lower in patients with ALL relapse. To address this assumption and to investigate the prognostic significance of TEL-AML1 expression in relapsed childhood ALL, bone marrow samples of 146 children were analyzed by reverse-transcriptase (RT)-polymerase chain reaction (PCR). All children were treated according to Berlin-Frankfurt-Münster (BFM) ALL relapse trial protocols (ALL-REZ BFM 90-96). Their clinical features and outcome were compared with those of 262 patients who could not be tested due to lack of bone marrow samples. Thirty-two of 146 children with relapsed ALL were TEL-AML1-positive. Four of the negative patients had T-lineage and nine Philadelphia chromosome (Ph)-positive leukemia. Thus, the incidence of TEL-AML1 in relapsed Ph1-negative, B-cell precursor ALL is 32 of 133 (24%). The 32 TEL-AML1-positive and 101 negative patients differed significantly with respect to duration of last remission (42.5 v 27 months; P = . 0001) and age at initial diagnosis (53.5 v 74 months; P = .0269). At a median follow-up time of 21.5 months, children positive for TEL-AML1 had a significantly (P = .0011) higher probability of event-free survival (EFS; 0.79 v 0.33). The predominant majority of patients had been treated for initial ALL according to German multicenter BFM (108 of 133) or Cooperative ALL study group (CoALL) (19 of 133) frontline protocols. The comparison of tested and not-tested (N = 262) patients showed no significant difference. TEL-AML1 positivity predicted a favorable short-term outcome; long-term results are unknown. Screening for TEL-AML1 should become routine at relapse diagnosis and might be used for therapy stratification in future trials.

[Organization of the Pediatric Tumor Cell Bank of the Society of Pediatric Oncology and Hematology (GPOH)]

Characterized cell lines are absolutely necessary in applied research of cell biology and medicine. For the completion of diagnosis and therapy especially in pediatric oncology we are establishing a Cell Bank for Pediatric Tumors. The Cell Bank for Pediatric Tumors collects tissue samples of different types of solid malignant tumors from children and young adults. The specimens are transferred to in vitro culture (guidelines of the American Type Culture Collection-ATCC), the resulting cells are characterized to assure accordance with the histogenesis of the original tumor and stored in liquid nitrogen. The cell cultures are characterized morphologically (phase contrast microscopy) and immunocytochemically (ABC-method). To prove the malignancy of cells in primary culture the amount of hypertetraploid cells was determined (DNA-Scanning-Cytophotometry). Cell lines are checked to find out whether they develop tumors in nude mice followed by an analysis of the karyotype. Additional investigations (e.g. in vitro test of cytostatic drug resistance) are carried out on request by the sender. Part of the tumor tissue which is used to start the cell culture is in parallel diagnosed histopathologically at the Children's Tumor Register, Kiel and/or at the Charité. By the end of the year 1995 the Cell Bank for Pediatric Tumors had received 183 different specimens including 123 solid tumors (e.g. 24 neuroblastomas, 18 osteosarcomas, 12 Wilms' tumors, 13 rhabdomyosarcomas), 44 tissue specimens without any malignant cells, 8 probes without vital cells and 8 leukemias and lymphomas. We were able to establish primary cell cultures of 50% of the sterile tumor tissue probes, to cultivate them for a minimum of 5-10 passages, to characterize and freeze them. Six out of these tumor cell lines were already cultivated for one year and are available to the scientific community.

Prognostic factors and staging systems in childhood hepatoblastoma

The objectives of this study were to investigate clinical and patho-histological characteristics of childhood hepatoblastoma on their value as prognostic factors, and to evaluate the predictive impact of different staging systems for liver tumors on 72 patients treated in the German Pediatric Liver-Tumor Study HB89. Statistical analysis was performed by comparing patients' disease-free survival with characteristics and stages. Multivariate analysis was done by the Cox proportional-hazards model, the recursive partitioning and amalgamation model (RECPAM) and the model of clustering by response (CBR). The following characteristics were significantly related with prognosis: tumor involvement of one vs. both liver lobes, multifocal disseminated vs. unifocal growth pattern in the liver, distant metastases, vascular invasion, fetal vs. embryonal differentiation, and serum alpha-fetoprotein; patients with values of < or = 100 ng/ml or > or = 1,000,000 ng/ml had a worse outcome than those with 100 to 1,000,000 ng/ml. Multivariate analysis with the 3 models revealed that tumor-growth pattern, serum alpha-fetoprotein and, in the Cox and CBR models, vascular invasion also are independent prognostic factors, permitting the allocation of hepatoblastoma patients to 1 of 2 prognostic groups for differential therapy. Post-surgical staging and the conventional TNM system for liver carcinoma had a high predictive value, in contrast to a TNM system proposed by the UICC for testing on childhood liver tumors. We therefore propose that the TNM system for liver carcinoma be applied for comparison of treatment results in hepatoblastoma.

The current contribution of molecular factors to risk estimation in neuroblastoma patients

The association of molecular characteristics with prognosis has been reported, but not their relationship with each other and their impact in the context of known clinical risk factors. In this study, data of 1249 consecutive intent-to-treat-neuroblastoma patients with more than 1 year follow-up were examined by multivariate analysis using loglinear and Cox proportional hazard regression models on a stage-related basis (stages 1-3: 600, 4S: 116, 4: 533). In a first step, risk factors were identified from 18 selected clinical variables, and risk groups defined. The second step investigated whether molecular characteristics (MYCN, LOH 1p, del 1p, CD44, N-ras, NGF-R, bcl-2, APO-1 (CD95)) contributed additional prognostic information to the model. The loglinear model demonstrated several interactions between clinical factors. By the Cox regression model, seven independent clinical risk factors were found for stages 1-3, seven for stage 4 and two for stage 4S. By subsequent introduction of all molecular variables, MYCN amplification only added significant prognostic information to the clinical factors in localised and stage 4 neuroblastoma. The models allowed the definition of risk groups for stages 1-3 patients by age (e beta = 5.09) and MYCN (e beta = 4.26), for stage 4 by MYCN (e beta = 2.78) and number of symptoms (e beta = 2.44) and for stage 4S by platelet count (e beta = 3.91) and general condition (e beta = 2.99). Molecular factors and in particular MYCN contribute significantly to risk estimation. In conjunction with clinical factors, they are powerful tools to define risk groups in neuroblastoma.

Treatment results in children and adolescents with loco-regional recurrences of abdominal germ cell tumors (GCTs): a pilot-study with PEI chemotherapy and regional deep hyperthermia (RHT) in comparison to a matched cohort

In this study treatment results in children and adolescents (n = 32) suffering from loco-regional abdominal relapses of germ cell tumors (GCT) (7 embryonal carcinoma, 17 Yolk sac tumors, 8 immature teratomas) aged from 1;0 to 23;3 years (mean = 10;11 years) were evaluated. In this pilot study 9 patients were treated with cisplatinum (40 mg/m2 on days 1 and 4), etoposide (100 mg/m2 on days 1 to 4), and ifosfamide (2000 mg/m2 on days 1 to 4) (PEI) +/- radiation in combination with regional deep hyperthermia (RHI). In sedation RHT was induced by non-invasive heat applicators (Sigma-40 and Sigma 60, BSD Medical Corporation, Utah, USA). In 7 out of these 9 patients with recurrent GCT a tumor response (5 CR, 2 PR, 1 SD, 1 PD) was found. In addition, in 2 patients a complete tumor resection could be achieved inspite of 2 previous incomplete tumor resections each. Five out of 9 patients are living event-free after an observation period ranging from 8 to 40 months (median = 15 months). Treatment results of this RHT study population were compared with treatment results in patients with recurrent GCT, who received conventional relapse therapy (chemotherapy/ surgery +/- radiation) alone. In this matched cohort 5 out of 23 patients are living event-free after an observation time ranging from 1 to 120 months (median = 8 months). According to Kaplan-Maier life table analysis, patients with relapse therapy combined with RHT have an event-free survival (EFS) of 0.41 +/- 0.33 whereas the matched cohort without RHT have an EFS of 0.16 +/- 0.25. The difference in treatment results of both groups is significant (Wilcoxon/p = 0.03). From the data presented in this study we conclude that children with loco-regional recurrences of extracranial non-testicular GCT have an unfavorable prognosis, unless local tumor control can be achieved. The additional application of RHT in combination with conventional therapy (PEI chemotherapy +/- radiation) can improve local tumor control and EFS in GCT patients with loco-regional recurrences. Therefore, based upon these results in the future MAKEI trial RHT will be applied to GCT patients with poor response to neoadjuvant chemotherapy alone as first line treatment.

Extracranial non-testicular teratoma in childhood and adolescence: introduction of a risk score for stratification of therapy

PATIENTS AND METHODS

According to previous literature incomplete tumor resection, coccygeal or ovarian primary site and immaturity are known risk factors for relapse in teratoma. To establish a risk score points are allocated for resection, primary site and histology in the following manner and added: incomplete resection 4 points, primary site coccyx 3 points, ovary 2 points, other site 1 point, histological grading 0-3 points. This score system is evaluated on 270 extracranial non-testicular teratoma cases collected between 1982 and 1995 in the MAKEI cooperative treatment protocols of the German Society of Pediatric Oncology and Hematology. Treatment was resection alone (230 patients) or resection followed by postoperative adjuvant chemotherapy (40 patients).

RESULTS

Patients treated with surgery alone: 28/230 (12%) patients relapsed, 14/230 (6%) patients showed highly malignant histology (mostly yolk sac tumor) in relapse. Mortality in case of relapse was 6/28 (21%). Patients scoring > or = 6 points (n = 45) had a relapse rate of 21/45 (47%) resulting in a 23%-mortality (5/21). Patients scoring < 6 points (n = 185) had a 4%-relapse risk (8/185) resulting in 13%-mortality (1/8) (p < 0.01). Patients treated with surgery and adjuvant chemotherapy: 7/40 patients (18%) suffered a relapse, none of them showing malignant histology. Mortality rate in case of relapse was 3/7 (43%). Patients scoring > or = 6 points initially treated with adjuvant chemotherapy (n = 18) had a relapse rate of 7/18 (39%), compared to patients scoring < 6 points (n = 22), in whom no relapses occurred (p < 0.01). There were no highly malignant relapses in the group treated with adjuvant chemotherapy. Regardless of the scored points the difference in highly malignant relapse histology comparing the group treated with surgery and adjuvant chemotherapy to the group treated with surgery was statistically significant (p = 0.02).

CONCLUSION

The risk score system marks a high risk group including 63/270 (23%) of all evaluated extracranial non-testicular teratoma cases (scoring > or = 6 points). In this group 28/35 (80%) of relapses and 8/9 (89%) of tumor deaths occurred. For this high risk group a randomized trial will be suggested to evaluate the effect of adjuvant chemotherapy on the rate of malignant relapses. It should also be investigated, if adjuvant chemotherapy will influence relapse rate and mortality.

Successful systemic low-dose lysis of a caval thrombus by rt-PA in a neonate with congenital nephrotic syndrome

PURPOSE

Thrombotic complications in nephrotic syndrome due to renal loss of antithrombin III (AT III) are well known. With this case report, we want to demonstrate the possibility of achieving the lysis of such a thrombosis in the neonatal period with low-dose rt-PA.

PATIENTS AND METHODS

We treated a 10-day-old newborn who had congenital nephrotic syndrome, who developed a caval thrombosis during the first days of his life. After a trial of heparin (up to 20 IU/kg/hour) over a period of 24 hours and treatment with AT III (2 x 250 IU/day) proved to be ineffective, we started systemic thrombolytic therapy with rt-PA. An initial bolus of 0.4 mg/kg during 1 hour was followed by an infusion of 0.5 mg/kg/d rt-PA over a period of 36 hours. Low-dose heparin (5 IU/kg/hour) was given simultaneously. Complete clot dissolution could be achieved this way. No adverse effects were observed, including no clinical signs of bleeding.

CONCLUSION

It seems that low-dose rt-PA treatment is safe and effective in dissoluting large caval thromboses in neonates.

Efficiency and toxicity of ifosfamide, cisplatin and doxorubicin in the treatment of childhood hepatoblastoma. Study Committee of the Cooperative Paediatric Liver Tumour Study HB89 of the German Society for Paediatric Oncology and Haematology

The Cooperative German Paediatric Liver Tumour Study HB89 was conceived to evaluate the efficiency and toxicity of ifosfamide, cisplatin and doxorubicin (IPA) in children with resectable and non-resectable hepatoblastoma (HB) and to determine late sequelae including tubular nephropathy of tumour treatment. The study also assessed the results of a surgical strategy, which adapts the procedure at the initial operation to the tumour's extension in the liver. The relationship of the tumours' histological differentiation to response to chemotherapy was also examined. Patients with a HB restricted to one liver lobe underwent primary resection. Larger tumours were initially treated with IPA chemotherapy and resected at second-look surgery. All patients received IPA adjuvantly after tumour resection. The IPA regimen consisted of ifosfamide 3.5 g/m2 (over 72 h days 1-3), cisplatin 100 mg/m2 (over 5 days 4-8) and doxorubicin 60 mg/m2 (over 48 h, days 9-10). Median follow-up of survivors was 64 months (range 28-82). Long-term disease-free survival (DFS) was for stage I: 21/21; stage II: 3/6; stage III: 28/38; and stage IV: 2/7 (overall 75%). Severe surgical complications occurred in 15% (4/27) of primary and 21% (8/38) of secondary resections with no lethality. 44/45 stage III/IV HB displayed PR after two IPA courses. Drug resistance developed in 8/12 tumours after four or five chemotherapy courses. Acute toxicity was observed in 34/242 (14%) IPA courses. Late sequelae were found in 7/54 (13%) of survivors, and subclinical renal tubulopathy occurred in 7/41 investigated patients (17%). Despite a more favourable prognosis in pure fetal and predominantly fetal histology, statistical analysis revealed no relationship between tumour differentiation and response to chemotherapy. In conclusion, IPA chemotherapy in combination with delayed surgery was highly effective in the treatment of HB.

Juvenile granulosa cell tumors of the ovary in children and adolescents: results from 33 patients registered in a prospective cooperative study

Clinical and pathological data from 33 prospective registered patients who suffered from juvenile granulosa cell tumors (JGCT) were evaluated according to treatment and outcome. The median age at the time of diagnosis was 7.6 years (range, 6 months to 17.5 years). Fourteen patients showed signs of a pseudo-precocious puberty. In 1 patient premenarcheal bleeding was the only clinical symptom of the disease. A pelvic tumor or an abdominal distention was found in 6 children, revealing signs of an acute abdomen in 3 children. Tumor staging was performed according to the FIGO (International Federation of Gynecology and Obstetrics) classification for ovarian tumors. Twenty children and adolescents were classified as FIGO stage Ia; 8 children had stage Ic tumors. In 4 patients stage IIc and in 1 patient stage IIIc tumors were observed. For local tumor control all 33 patients underwent tumor resection and oophorectomy, which was complete in 28 patients. Adjuvant combination chemotherapy was used in 1 girl who presented with high mitotic pathological index features in FIGO stage Ia. In 8 other children between FIGO stage Ic and IIIc, treatment was also intensified by multidrug chemotherapy. After a follow-up period of 168 months, an event-free survival of 0.75 +/- 0.07 was observed. From our data we conclude that multidrug chemotherapy including cisplatin-based regimens may be useful to enhance treatment results of JGCT, especially in advanced FIGO stages.

Correlation of germ-line mutations and two-hit inactivation of the WT1 gene with Wilms tumors of stromal-predominant histology

The WT1 gene, located on chromosome 11p13, is mutated in a low number of Wilms tumors (WTs). Germ-line mutations in the WT1 gene are found in patients with bilateral WT and/or associated genital tract malformations (GU). We have identified 19 hemizygous WT1 gene mutations/deletions in 64 patient samples. The histology of the tumors with mutations was stromal-predominant in 13, triphasic in 3, blastemal-predominant in 1, and unknown in 2 cases. Thirteen of 21 patients with stromal-predominant tumors had WT1 mutations and 10 of these were present in the germ line. Of the patients with germ-line alterations, six had GU and a unilateral tumor, two had a bilateral tumor and normal GU tracts, and two had a unilateral tumor and normal GU. Three mutations were tumor-specific and were found in patients with unilateral tumors without GU. These data demonstrate a correlation of WT1 mutations with stromal-predominant histology, suggesting that a germ-line mutation in WT1 predisposes to the development of tumors with this histology. Twelve mutations are nonsense mutations resulting in truncations at different positions in the WT1 protein and only two are missense mutations. Of the stromal-predominant tumors, 67% showed loss of heterozygosity, and in one tumor a different somatic mutation in addition to the germ-line mutation was identified. These data show that in a large proportion of a histopathologically distinct subset of WTs the classical two-hit inactivation model, with loss of a functional WT1 protein, is the underlying cause of tumor development.

Testicular juvenile granulosa cell and Sertoli cell tumours: a clinicopathological study of 29 cases from the Kiel Paediatric Tumour Registry

Testicular Sertoli cell tumours (SCT) and juvenile granulosa cell tumours (JGCT) are rare in childhood. This study was designed to investigate the clinical picture, morphology and disease course in a comparatively large series of cases (total number = 29). Of 198 cases of childhood testicular tumour documented in the Kiel Paediatric Tumour Registry 18 were cases of infantile SCT (9.1%) and 11 of JGCT (5.6%). The average age at the time of diagnosis was 4.2 months for infantile SCT and 0.4 months for IGCT. SCT and JGCT often showed infiltrative growth into adjacent testicular tissue, dense cellularity and considerable proliferation activity. Immunohistochemically all cases expressed vimentin intermediate filaments in both tumour types. Next in frequency of expression were cytokeratins (SCT: 7/16; JGCT: 7/10) and smooth-muscle actin (SCT: 9/15; JGCT: 4/10). Follow-up studies (24/29) showed that in cases of tumour manifestation in infancy and after complete tumour removal (usually orchiectomy) no local recurrences and no metastases occurred. The most important conclusion for diagnosis and therapy is that despite infiltrative growth, incomplete differentiation, dense cellularity and considerable proliferation activity, after surgical excision infantile SCT and JGCT have a good prognosis. Adjuvant chemotherapy or more extensive operations with lymphadenectomy are thus not indicated.

In vitro culture studies of childhood myelodysplastic syndrome: establishment of the cell line MUTZ-1

Myelodysplastic syndrome (MDS) in childhood is considered to be very rare and detailed pathobiological data are scarce. More biological information regarding MDS in children is clearly needed and in vitro culture studies provide one possibility for gaining further pathophysiological insights into this malignancy. Here, we incubated bone marrow samples from 30 children with MDS in liquid suspension culture in order to grow the transformed cells in vitro. In most cultures, the hematopoietic cells died quickly and only fibroblastic (stromal) background layers proliferated temporarily; several normal Epstein-Barr virus (EBV)-transformed B-lymphoblastoid cell lines (B-LCL) were established. Only in one instance, albeit from the peripheral blood and not from the bone marrow, could we establish a cell line, termed MUTZ-1, from the malignant cells of a 5-year-old girl with MDS (FAB subtype refractory anemia with excess of blasts). The MDS arose from a pre-existing Fanconi anemia and progressed quickly to an acute myeloid leukemia (FAB M2). Despite positivity for EBV, MUTZ-1 is not an EBV + B-LCL and further characterization of MUTZ-1 confirmed the derivation from the transformed clonal cells. Immunophenotyping showed a pre B-cell surface marker profile (CD10+ CD19+ cytoplasmic IgM+); receptor gene rearrangement analyses underlined the clonal B-cell nature of MUTZ-1 cells. MUTZ-1 cells exhibit a highly rearranged, unstable karyotype with a high frequency of spontaneous chromatid breaks and exchanges; del(5q) and additional rearrangements involving chromosome 5 [der(15)t(5;15)] were detected. The present data and results from a few other MDS-derived cell lines suggest that the transforming event in MDS seems to occur in an immature pluripotent progenitor cell. The new MDS-derived continuous cell line MUTZ-1 provides a useful in vitro model system for studies on the pathogenetic events leading to MDS.

Congenital intracerebral teratoma: a rare differential diagnosis in newborn hydrocephalus

Congenital hydrocephalus is caused by a broad spectrum of underlying disorders. In the majority of cases it is due to aqueductal stenosis and other distinct congenital anomalies, like Arnold-Chiari malformation. Nevertheless, in the differential diagnosis rare conditions such as cerebral malignancies must also be considered. We present two cases of congenital intracerebral teratoma as a differential diagnosis in congenital obstructive hydrocephalus. A teratoma is suggested when a rapidly growing hydrocephalus with a central calcified and vascularized mass is found sonographically. Regular cerebral structures usually cannot be detected. Early diagnosis in such cases is of clinical importance as the prognosis of congenital intracerebral teratoma is generally very poor.

Giant cell tumor of the larynx: case report and review of the literature

BACKGROUND

Primary manifestation of a giant cell tumor (GCT) in the larynx is exceedingly rare. Until now, only 17 cases have been reported in the literature. Characterization of a GCT can be difficult partly because of similarities with the giant cell subtype of malignant fibrous histiocytoma (MFH).

METHODS

The case of a 35-year-old man with a laryngeal GCT is presented. The patient underwent laryngectomy and has been free of recurrence since then (90 months). The literature is reviewed, and previously reported cases are presented in a table and compared with the presented case. The difficulties in the differential diagnosis are discussed.

CONCLUSIONS

When a laryngeal GCT is diagnosed, further differential diagnostic considerations should follow. One of these considerations is the MFH, which displays considerably more cellular atypia than GCT. Because most cases of giant cell MFH are high-grade sarcomas, the distinction between GCT and MFH is necessary.

Detection of rare RNA sequences by single-enzyme in situ reverse transcription-polymerase chain reaction. High-resolution analyses of interleukin-6 mRNA in paraffin sections of lymph nodes

To study the distribution pattern of interleukin-6 (IL-6)-producing cells in normal human lymph nodes, we applied the in situ reverse transcription-polymerase chain reaction technique. We describe a new modification of this technique for monitoring small amounts of specific nucleotide sequences in conventional paraffin sections. This technique differs in at least two respects from those described earlier. The two decisive steps are: 1) the reverse transcription of mRNA and the subsequent amplification of cDNA by polymerase chain reaction are performed by a new single enzyme capable of both reaction types in one and the same medium without buffer exchange; and 2) for the specific detection of the amplified cDNA, a modified version of the primed in situ labeling technique was used. The technique, carried out on normal human lymph nodes, traces a low load of IL-6 mRNA in fibroblasts, endothelial cells, and a minor population of T lymphocytes in the pulp region. High levels of expression were encountered in about 20% of perisinusoidal pulp macrophages. In addition, moderate activity was detectable in sinus lining cells. Because no major activity was found in the germinal centers of the lymphoid B follicles and in the T zone, it is suggested that the plasma cell differentiation ensuing from primary and secondary B-cell immunization is mainly effected by the sinus lining cells as well as perifollicular and perisinusoidal pulp macrophages capable of producing high amounts of IL-6.

Prognostic significance of the proliferative activity in neuroblastoma

The prognostic significance of the immunohistochemically assessed growth fraction in neuroblastomas was determined in relation to tumor grade and tumor stage. A total of 101 cases of neuroblastoma were examined with the monoclonal antibodies PC10 against proliferating cell nuclear antigen (PCNA) and Ki-S5 against the Ki-67 protein. Patients were followed for a mean time of 4.8 years. Expression of both PC10 and Ki-S5 was found to be significantly linked to tumor grade and tumor stage. Prognostically favorable stage IVs was associated with low PCNA and Ki-S5 levels. For ganglioneuroblastoma, significant differences were found between the diffuse and the composite type. In univariate analysis of stage III and IV tumors, Ki-S5 and PCNA scores were significantly correlated with disease-free survival (P < 0.0015), allowing definition of a subset of cases with favorable outcome. As to Shimada's group with poor prognosis, significant differences in the clinical course were found for low and high Ki-S5 scores (P = 0.036) but not for PCNA. In multivariate analysis, only patient age, Shimada's grade, and Ki-S5 scores achieved prognostic significance. We conclude that proliferation marker Ki-S5 may provide substantial prognostic information and might become a useful adjunct for predicting the clinical courses of neuroblastoma.

In vitro fibrinolysis after adding low doses of plasminogen activators and plasmin generation with and without oxidative inactivation of plasmin inhibitors in newborns and adults

PURPOSE

The aim of this study was to investigate in vitro fibrinolysis after adding low doses of plasminogen activators and to determine the functional role of plasmin inhibitors in newborns and adults.

PATIENTS AND METHODS

We have studied the kinetics of in vitro fibrinolysis after adding low doses of urokinase (UK) and recombinant tissue plasminogen activator (rt-PA) by use of a microtiter clot lysis assay. Additionally, we have determined plasmin generation with and without oxidative inactivation of plasmin inhibitors in newborns and adults.

RESULTS

The 50% lysis time in the clot lysis assay correlated with the activator dose and was significantly shorter in newborns at rt-PA concentrations of < 0.21 microgram/ml. When UK was used as an activator, the 50% lysis time was slightly but significantly prolonged in newborns at concentrations of 140-200 IU/ml, whereas we could find lower values (non-significant) at 110 and 80 IU/ml. Plasmin generation after oxidative inactivation of plasmin inhibitors was significantly lower in newborns, even when compared with adult plasma, which was diluted 50%. However, in a physiological plasma milieu (containing natural inhibitors), there were no differences in plasmin generation when streptokinase (SK) was used as an activator and only minor differences when UK was used.

CONCLUSIONS

Our data indicate a more rapid clot lysis at low UK and rt-PA concentrations in newborns despite significantly reduced plasminogen levels. The results of the plasmin generation experiments suggest a diminished effect of plasmin inhibitors towards fetal plasmin, which raises an explanation for the concentration-related differences in the clot lysis assay. The experience with thrombolytic agents in newborns is limited. Most dosage regimens for thrombolytic therapy in children or adults consist of an initial bolus infusion, followed by low-dose continuous treatment. Based on the results of our clot lysis experiments, we think that especially the continuous infusion of plasminogen activators after bolus administration should not be enhanced in newborns compared to older children or adults.

[Changes in the activation markers of blood coagulation and fibrinolysis in the neonatal period]

BACKGROUND

Activation markers of the clotting and fibrinolytic systems are elevated immediately after birth and decline to near adult levels during the first 24 hours of life. The aims of this study were to investigate, whether the activation of both clotting and fibrinolysis is dependent on the mode of delivery, and to measure activation markers in newborns with infection beyond the first days of life.

PATIENTS

We have studied activation markers thrombin-antithrombin III complex, prothrombin fragment 1 + 2, D-dimer and plasmin-antiplasmin complex by use of commercially available ELISA techniques in 20 newborns after elective Cesarean sections because of previous sections, in 20 newborns after Cesarean sections and a trial of labor with uterine contractions over a period of > 20 hours and in 20 newborns (34.-41. gestational week) aged 10-25 days with infection. 20 healthy adults served as controls.

RESULTS

A significant elevation of all activation markers was observed both in the newborns after Cesarean sections and in the 10-25 days old children with infection. There were no differences among newborns after elective sections compared to newborns after section and a trial of labor with uterine contractions over a period of > 20 hours.

CONCLUSIONS

The clotting and fibrinolytic systems reveal increased activation immediately after delivery, but uterine contractions over a period of > 20 hours seem not to make a difference. During infection, the activation markers of the hemostatic system in newborns aged 10-25 days behaves similarly to the mature adult system.