Central nervous system tumours in adolescents.

Adolescents with brain tumours have been, and in most cases still are, haphazardly assigned, on referral, to either 'paediatric' or 'adult'-based treatment centres. In this age group, there is therefore a history of inconsistent treatment, delivery of inappropriate 'maturity-related' care and a reduced chance of gathering vital biological, clinical and treatment-related information germane to this group of patients and their tumours. These days, adolescents with brain tumours should be actively targeted for recruitment into clinical trials and admission into dedicated neuro-oncology centres or programmes that can deliver the necessary and age appropriate multidisciplinary management.

Growth hormone replacement therapy in children with medulloblastoma: use and effect on tumor control.

PURPOSE: Progress has been made in the treatment of medulloblastoma, the most common childhood malignant brain tumor: However, many long-term survivors will have posttherapy growth hormone insufficiency with resultant linear growth retardation. Growth hormone replacement therapy (GHRT) may significantly improve growth, but there is often reluctance to initiate GHRT because of concerns of an increased likelihood of tumor relapse. PATIENTS AND METHODS: This study retrospectively reviewed the use of GHRT for survivors of medulloblastoma in 11 neuro-oncology centers in North America who received initial treatment for disease between 1980 and 1993 to determine its impact on disease control. A Landmark analysis was used to evaluate the relative risk of relapse in surviving patients. RESULTS: Five hundred forty-five consecutive patients less than 15 years of age at diagnosis were identified. Six-year progression-free survival (mean +/- SD) was 40% +/- 5% in children less than 3 years of age at diagnosis compared with 59% +/- 3% for older patients. Older patients with total or near-total resections (P = .003) and localized disease at diagnosis (P < .0001) had the highest likelihood of survival. One hundred seventy patients (33% +/- 3% of the cohort) received GHRT. GHRT use varied widely among institutions, ranging from 5% to 73%. GHRT was begun a mean of 3.9 years after diagnosis, later in children younger than 3 years at diagnosis (5.4 years). By Landmark analyses, for those surviving 2, 3, and 5 years after diagnosis, there was no evidence that GHRT increased the rate of disease relapse. CONCLUSION: This large retrospective review demonstrates that GHRT is underutilized in survivors of medulloblastoma and is used relatively late in the course of the illness. GHRT is not associated with an increased likelihood of disease relapse.

Choroid plexus tumors in children: significance of stromal invasion.

OBJECTIVE: A group of choroid plexus tumors fit the cellular criteria for choroid plexus papilloma (CPP) except for invasion into the adjacent parenchyma, with associated loss of the normal villus architecture at the site of invasion. These tumors retain a benign cellular appearance. In the existing literature, it is unclear whether these tumors are classified as choroid plexus carcinomas or as CPPs. In our experience, although evidence of invasion is present, these tumors tend to exhibit benign behavior. We suggest that stromal invasion of this type remains consistent with a benign clinical course, although surgical results may demonstrate higher morbidity rates, given the invasive nature of the tumors. The failure to classify these tumors as CPPs may explain some of the variability in outcomes reported for various studies. METHODS: To study this question, clinical and histological data for children diagnosed with CPPs (either with or without stromal invasion) between 1985 and 1995 were examined. Only cases with pre- and postoperative magnetic resonance imaging data were included in the series. RESULTS: A total of 12 patients with CPPs were identified, with 4 tumors being notable for stromal invasion. After gross total tumor removal, none of the eight children with CPPs received adjuvant therapy at our institution; all are alive without evidence of tumor recurrence after surgical excision (mean, 108 mo). Of the four patients with stromal invasion, three underwent gross total resection. The one patient who underwent subtotal resection received chemotherapy at another facility. All four of these patients are alive, after a mean of 100 months of follow-up monitoring. CONCLUSION: It is recommended that CPPs with a benign cellular appearance but with evidence of local parenchymal invasion and loss of the normal villus architecture at the site of invasion be classified as CPPs. Patients with these tumors respond to surgical therapy alone, without the need for adjuvant treatment.

Physiological optics and physical geometry.

Hermann von Helmholtz's distinction between "pure intuitive" and "physical" geometry must be counted as the most influential of his many contributions to the philosophy of science. In a series of papers from the 1860s and 70s, Helmholtz argued against Kant's claim that our knowledge of Euclidean geometry was an a priori condition for empirical knowledge. He claimed that geometrical propositions could be meaningful only if they were taken to concern the behaviors of physical bodies used in measurement, from which it followed that it was posterior to our acquaintance with this behavior. This paper argues that Helmholtz's understanding of geometry was fundamentally shaped by his work in sense-physiology, above all on the continuum of colors. For in the course of that research, Helmholtz was forced to realize that the color-space had no inherent metrical structure. The latter was a product of axiomatic definitions of color-addition and the empirical results of such additions. Helmholtz's development of these views is explained with detailed reference to the competing work of the mathematician Hermann Grassmann and that of the young James Clerk Maxwell. It is this separation between 1) essential properties of a continuum, 2) supplementary axioms concerning distance-measurement, and 3) the behaviors of the physical apparatus used to realize the axioms, which is definitive of Helmholtz's arguments concerning geometry.

DNA determination in dysplastic nevi. A comparative study between flow cytometry and image analysis.

Dysplastic nevi (DN), described in 1978, have been associated with increased risk of melanoma, but the role of DN as precursors of melanoma is still controversial. Recent studies have shown that DN are very common in the general population, bringing into question this purported association. Numerous investigations have attempted to correlate the presence of DN in individuals with specific phenotypic and genotypic features, including the presence of abnormal DNA content. Because the occurrence of such abnormal DNA stemlines in neoplasms may be associated with malignant behavior, we studied 38 biopsies from 19 patients that histologically fulfilled criteria for DN in order to ascertain characteristics of DNA content. Nuclear suspensions made from paraffin-embedded tissue were evaluated by both flow cytometry and image analysis techniques. All cases demonstrated diploid populations by both DNA measurement methods. Our results contradict previous reports of aneuploid populations in these melanocytic lesions.

Intravascular lymphomatosis: report of an unusual case with T cell phenotype occurring in an adolescent male.

Intravascular lymphomatosis is a rare disorder which most often occurs in the elderly. The overwhelming majority of the cases studied immunophenotypically have expressed a B cell phenotype. We report an unusual case of T cell intravascular lymphomatosis occurring in an adolescent male.

Comparison of image analysis with flow cytometry for DNA content analysis in pigmented lesions of the skin.

The DNA ploidy of 85 melanocytic skin lesions was determined by flow cytometry (FCM) and interactive image analysis (IA) using nuclear extracts of paraffin-embedded tissue. Of the 85 lesions analyzed, 43 were malignant melanomas in different stages of evolution, 15 were dysplastic nevi, 11 were Spitz nevi, and 16 were other types of nevi. Some of the last had features of congenital nevi. Within the melanoma category, there was 42% aneuploidy by FCM versus 56% by IA. Of those melanomas aneuploid by FCM, all but one were aneuploid by IA. All dysplastic nevi, 10/11 Spitz nevi and 15/16 other nevi were diploid by both methods. One of the 16 nevi from the "other types" category was tetraploid by IA but diploid by FCM. A single Spitz nevus was tetraploid by FCM but diploid by image analysis. While our results suggest that interactive IA is potentially a more sensitive method than FCM for detecting aneuploidy in cutaneous pigmented lesions, it remains to be shown whether this will translate into better prognostic assessment of the biologic behavior of melanocytic neoplasms than provided by flow cytometric ploidy analysis.

Rearrangement of immunoglobulin and T-cell receptor genes in Hodgkin's disease.

The precise cellular origin of the malignant cell population in Hodgkin's disease (HD) is unknown. Recent application of Southern blotting techniques to detect clonal rearrangements of immunoglobulin (Ig) and T-cell receptor (TCR) genes has yielded conflicting results. The authors report the detailed analysis of tumor tissue DNA obtained from 18 cases of HD using Ig and TCR gene probes. The distribution of HD subtypes was similar to that in other series. Samples were examined for rearrangement by means of multiple restriction enzymes with specific probes for the Ig heavy chain, Ig kappa, Ig lambda, TCR beta, and TCR gamma loci. Only germline bands were detected in all 18 cases with the Ig gene probes and in 15 of 18 cases with the TCR probes. In 2 cases blot analysis suggested a predominance of polyclonal (or oligoclonal) T cells. In 1 case monoclonal rearrangement of the TCR beta gene was detected. Based on the intensity of the rearrangement and the small percentage of Reed-Sternberg (R-S) cells in this case, the clonal population detected was most likely not the R-S cell itself. The data do not support the frequent occurrence of Ig or TCR monoclonal gene rearrangement in HD.

Ki-1 lymphomas in children.

Three male children, ages 8, 11, and 14 at presentation, with the recently described Ki-1 lymphomas are reported. All three had lymph node involvement. The lymphoma was classified as immunoblastic in two children, and mixed small and large cell in the third child. In histologic terms, sinusoid, paracortical, and diffuse lymph node involvement by lymphoma was evident in each case. Both cases of immunoblastic lymphoma were T11+, T10+, T9+, HLA/Dr+, Tac+, Ki-1+, LCA+, and EMA+, while the lage neoplastic cells of the other case were T11+, Ki-1+, and LCA+. In all three cases DNA analysis of immunoglobulin heavy and light chain genes as well as T-cell receptor beta- and gamma-chain genes showed only germline patterns. The patients were treated with multi-agent chemotherapy. Two are in complete remission at 13 and 16 months, while the third failed to achieve remission and is alive with disease 12 months after a diagnosis had been established.

T-cell receptor gene rearrangement in regressing atypical histiocytosis.

A case of regressing atypical histiocytosis having characteristic clinical and light microscopic findings was studied immunologically for immunoglobulin and T-cell receptor gene rearrangement and for DNA ploidy analysis. Immunologic phenotyping and rearrangement of T-cell receptor Beta- and gamma-chain genes indicated that this primary cutaneous neoplasm, previously considered "histiocytic" in origin, is most probably of T-cell lineage.

Utility of Leu M1 monoclonal antibody in the differential diagnosis of Hodgkin's disease.

We conducted a retrospective study of the utility of Leu M1 monoclonal antibody staining of paraffin-embedded tissue in the differential diagnosis of Hodgkin's disease (HD). Forty-two cases of HD of various histologic types and 33 cases of non-HD lymphomas and hyperplasias were stained with Leu M1 using the avidin-biotin-peroxidase complex technique. Varying numbers, but not all Reed-Sternberg (RS) and Hodgkin's cells in all 42 cases of HD, were Leu M1 positive. These cases included seven examples of interfollicular HD and nine cases of lymphocyte-predominance HD, eight of which were nodular. Four of five cases of immunologically proved T-cell lymphoma contained Leu M1-positive RS-like cells, and Leu M1-positive RS-like cells were noted in two of five cases of non-HD lymphoma that were not phenotyped but were morphologically consistent with T-cell lymphoma. We concluded that Leu M1 staining is an aid in the diagnosis of HD, but it cannot be used to differentiate HD from T-cell lymphoma containing RS-like cells.

Storage and transportation of lymphoid tissue for immunophenotyping.

Immunoperoxidase staining of frozen sections is a cost-effective technic for immunophenotyping cells of lymphoid tissue. Because this procedure is not performed in many institutions, a simple method to transport fresh tissue to centers performing these studies is required. Tissues in saline at refrigerator temperature may be successfully transported. In addition, in order to minimize laboratory expenses, lymphoid tissue can be kept refrigerated in saline until permanent sections are examined and immunodiagnostic procedures become necessary. In this study reproducible immunophenotyping of 12 samples of lymphoid tissue stored up to seven days was achieved.

Leu-M1-positive small cell carcinoma.

A case of metastatic small cell carcinoma of the lung is reported; initially, on the basis of morphology, phenotyping with monoclonal antibodies, and cytochemistry, the carcinoma was interpreted as a hematopoietic neoplasm. Noncohesive blast-like cells observed in bone marrow and lymph node biopsy specimens stained with the monoclonal antibodies Leu-M1 and OKIa1 and were also positive for nonspecific esterase and acid phosphatase. Although these findings suggested a monocytic origin for the neoplastic cells, further analysis, including ultrastructural examination, disclosed metastatic small cell carcinoma. This case illustrates the need for caution in the interpretation of staining with monoclonal antibodies because of the potentially wide range of normal and abnormal cells and tissues that may react with monoclonal reagents.

Effect of various storage conditions on a fluorescence polarization immunoassay for tobramycin.

The effects of various storage conditions on the results of a fluorescence polarization immunoassay for tobramycin were studied. Two venous blood samples (150 mL each) were drawn one hour and six hours after a single intramuscular dose of tobramycin. From each of these samples, which represented peak (6 micrograms/mL) and trough (1 microgram/mL) concentrations, aliquots of whole blood and of serum were prepared and stored in both glass and polypropylene containers. Serum samples were stored at -20 degrees C and assayed for tobramycin at intervals of 1-372 days. Samples of serum and whole blood were stored at 4 and 25 degrees C and assayed on days 1, 3, and 7. Mean tobramycin concentrations over time and between-run coefficients of variation were calculated for each set of samples. There was no substantial variation in tobramycin concentrations over time. Significant differences between tobramycin concentrations were noted only for peak serum samples in glass versus plastic containers at -20 degrees C and for trough serum samples stored in glass at -20 degrees C versus 25 degrees C. However, these differences were small and are unlikely to be clinically important. Under the conditions tested, the results of a fluorescence polarization immunoassay for tobramycin do not appear to be affected by storage time, storage temperature, container material, or storage medium (whole blood versus serum).

Stability of theophylline in human serum and whole blood.

The effect of various storage conditions on serum theophylline results using a fluorescence polarization immunoassay (FPI) method was studied. Two human subjects received sufficient oral theophylline to produce low and high therapeutic serum theophylline concentrations. Aliquots of venous whole blood (without anti-coagulant) and serum from each subject were sealed in polypropylene plastic and glass containers and stored at 4 degrees C and 25 degrees C. Additional aliquots of serum from each subject were stored in glass and polypropylene containers at -20 degrees C. FPI assays were performed on days 0 and 3 for room temperature serum samples, days 3 and 7 for refrigerated serum samples, and days 3, 7, 14, 28, 56, 168, and 336 for frozen serum samples. All whole blood samples were assayed on day 3 after removal of the clot. Some samples were tested using FPI for 1,3-dimethyluric acid, a metabolite of theophylline, and results from spiked samples and samples tested with high-pressure liquid chromatography were compared with FPI results to determine cross-reactivity of the metabolite. No appreciable change in the assayed theophylline values occurred under any storage temperature, nor was there any difference in results from samples stored in glass versus polypropylene containers. At a concentration of 20 micrograms/ml, 1,3-dimethyluric acid produced a cross-reactivity of 3.5% with the FPI system. The FPI method is not affected by storage of samples under the specified conditions over the time period studied.

A new chromosome abnormality in idiopathic sideroblastic anemia: 46,XY,del11q23.

A new marker chromosome, deletion 11q23, was observed with the Giemsa banding technique in the bone marrow of a patient with idiopathic sideroblastic anemia. The abnormality was not detectable in the peripheral blood or with nonbanded chromosome studies. Nineteen of 40 cases of this disorder studied and reported to date had chromosomal aberrations, although the majority had only nonbanded karyotypes performed. This apparently high incidence of chromosomal defects and the finding in the present case indicate that more banded-karyotype analyses are needed to assess the presence of possible nonrandom cytogenetic changes in idiopathic sideroblastic anemia.

The tissue culture and morphology of human breast tumor cell line BOT-2.

A continuous human breast tumor cell line (BOT-2) was derived from an infiltrating duct carcinoma. The tumor cell line was grown as a monolayer in flasks, but the cells could be readily adapted to growth in roller cultures. These studies indicate that BOT-2 cells have a 16- to 18-hr doubling time and a modal chromosomal number of 63. The original BOT-2 cell culture has been in continuous cultivation for almost 2 years and has been passed 137 times. The BOT-2 cell line has been differentiated from HeLa cells by isoenzyme studies and chromosomal analysis.