PubMed Health⌕ Search

Biomedical subjects

L Helson

Publications and source records attributed to L Helson.

At least 37 records · Page 2Linked to original sources
PubMed1990

Effects of a single course of deferoxamine in neuroblastoma patients.

A phase II trial of a single 5-day course of deferoxamine in 9 patients with neuroblastomas was completed. Within 2 days of completion of treatment responses were observed in 7 of 9 patients and there was no drug toxicity. These responses were a decrease in bone marrow infiltration and, in one patient, a measurable reduction in her tumor mass. We conclude that deferoxamine given as an 8-h i.v. infusion daily for 5 days at 150 mg/kg/day has antitumor activity.

Adolescent↗
PubMed1989

Expression of the cholecystokinin gene by cultured human primitive neuroepithelioma cell lines.

In this report we identify two cultured human primitive neuroepithelioma cell lines that express cholecystokinin (CCK) RNA and synthesize substantial amounts of pro-CCK, but differ in their ability to process the prohormone. Seven cultured human neural tumor lines, including two primitive neuroepitheliomas and five neuroblastomas, were screened for CCK gene expression using a CCK C-terminal RIA system, a RIA specific for the carboxy-terminal extension of prepro-CCK, and RNAse protection assays specific for CCK mRNA. RNA derived from the two primitive neuroepitheliomas yielded strong hybridization signals with CCK-specific probes. The five other neuronal tumors were negative for CCK mRNA. The two primitive neuroepitheliomas also synthesized substantial quantities of material reactive in the CCK carboxy-terminal extension RIA system. One of the tumors, Sk-N-Mc, postranslationally processed the CCK prohormonal material poorly, yielding only high mol wt CCK precursors and no immunoreactive CCK. The other, SK-PN-Dw, was able to process the prohormone, producing immunoreactive CCK-like material plus a peptide that immunochemically and chromatographically resembled the intact CCK C-terminal extension peptide. These cultured tumor lines should prove useful in furthering our understanding of the regulation of the CCK gene in human neuronal cells and will also provide an in vitro system for investigation of the posttranslational processing of the CCK preprohormone. In addition, the data demonstrate that screening procedures for examining peptide hormone expression by tumors are most comprehensive when specific molecular genetic probes are employed in addition to standard peptide assay methodology. Finally, these data suggest that CCK production may be a feature of some primitive neuroepitheliomas.

Animals↗
PubMed1988

Miliary pulmonary neuroblastoma. A risk of autologous bone marrow transplantation?

A case of miliary pulmonary neuroblastoma is described which occurred 8 months after autologous bone marrow transplantation for Stage IV neuroblastoma. The patient, a 4-year-old boy had pulmonary symptoms at this time. Disseminated metastatic disease was found, but there was no tumor at the primary site. This unusual pattern of relapse suggests that the patient's disseminated disease was related to infusion of malignant cells at the time of transplantation.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1988

Primitive neuroectodermal tumors of the chest wall.

Primitive neuroectodermal tumor (PNET) is a rare, highly malignant small-cell neoplasm that most often arises from the chest wall or paravertebral region. A patient is described from whom resection, intensive chemotherapy, and bone marrow transplant were unsuccessful. Eleven patients were treated between 1975 and 1985; there was only one long-term survivor (48 months) despite intensive multidisciplinary treatment. The median survival of 49 published cases was 9 months. Conservative resection minimizing disability, radiotherapy, and intensive chemotherapy remain valid options, but use of experimental agents as part of initial therapy seems justified. The role of autologous marrow transplant remains unclear.

Adult↗
PubMed1988

Sonographic diagnosis and follow-up of abdominal neuroblastoma.

Intraabdominal neuroblastomas were evaluated by sonography in 30 children, 18 of whom underwent 2-5 studies, for a total of 63 examinations. All tumors had a variable and inhomogeneous echo pattern, but the level of echogenicity and changes in echo texture with therapy were of no value in predicting the course of disease. Sonography was limited in delineating the extent of tumor and in following response to therapy. Total resolution of abdominal disease could not always be accurately diagnosed with sonography. Computed tomography is recommended to evaluate further those children in whom abdominal disease is thought to have resolved, since heavily calcified, residual neuroblastoma may be mistaken for bowel gas on sonography.

Abdominal Neoplasms↗
PubMed1988

Correlation between iodine-131 MIBG imaging and biological markers in advanced neuroblastoma.

I-131 metaiodobenzylguanidine (MIBG) imaging was performed in 38 patients with advanced neuroblastoma. Abnormal images were found in patients with elevations of urinary vanillylmandelic acid and dopamine and high serum neuron-specific enolase levels. Normal or minimal elevation of markers was seen in patients with negative images. In follow-up studies after chemotherapy, the disappearance of abnormal uptake was noted in those patients with normal marker values. A persistently abnormal uptake occurred in patients with high marker values. Conversion from a normal image to an abnormal image also occurred in patients whose markers became elevated. I-131 MIBG imaging is sensitive in detecting active foci of a neuroblastoma and is useful in monitoring chemotherapy in these patients.

3-Iodobenzylguanidine↗
PubMed1987

Primitive neuroectodermal tumor cell lines: chromosomal analysis of five cases.

A cytogenetic analysis of primitive neuroectodermal tumor (PNET) cell lines was undertaken. PNET are presumed to be embryologically related to, but clinically and histologically distinct from, other tumors of neuroectodermal origin, including neuroblastoma and retinoblastoma. No single chromosome abnormality was found in all five of the tumors studied. In three of the five cases, however, additional 1q material [either as extra chromosome #1 or i(1q)] was found in all cells, and in two of the five, monosomy 13 was noted in all cells; the possible significance of these findings is discussed.

Cell Line↗
PubMed1987

Coordinated use of sequentially escalated cyclophosphamide and cell-cycle-specific chemotherapy (N4SE protocol) for advanced neuroblastoma: experience with 100 patients.

A rationally devised induction regimen of vincristine, Adriamycin (Adria Laboratories, Columbus, OH), and sequentially-escalated cyclophosphamide (CPM), followed by S-phase-specific agents (5-fluorouracil [5-FU]/cytosine arabinoside [ara-C]/hydroxyurea), was used in 100 patients with neuroblastoma. Of 17 patients under 1 year of age at diagnosis, complete (CR)/good partial (GPR) responses with long-term disease-free survival were achieved in 11 (85%) of 13 new patients and in two of four previously treated patients; six of the GPRs also received myeloablative therapy with autologous bone marrow rescue to consolidate remission status. The 83 patients over 1 year of age at diagnosis included three groups: (1) 36 new patients whose N4SE included maximal-dose CPM (ie, up to 140 to 160 mg/kg/course); (2) an earlier group of 18 new patients whose N4SE included moderate-dose CPM (ie, up to 80 mg/kg/course); and (3) 29 previously treated patients who all received the maximal-dose N4SE regimen. For new patients, CR/GPR rates were 72% in the maximal-dose group v 39% in the earlier moderate-dose group (P = .029). A CR/GPR rate of 41% and a partial response rate of 17% were observed for the 29 previously treated patients, all but two of whom had large tumor burdens after therapy that included moderate doses of CPM. Despite consolidation with myeloablative therapy, many responders in the three groups ultimately relapsed. The N4SE was strongly myelosuppressive, but only two patients died from associated infection. Extramedullary toxicity was limited to hemorrhagic cystitis in four of 33 CPM previously treated patients; this problem did not occur in the 67 new patients. The data indicate that the maximal-dose N4SE is an effective induction regimen for neuroblastoma, can achieve marked regressions of disease resistant to less intensive therapy, and is sparing of major body organs. This high rate of remission induction must be coupled with improvements in consolidation therapy to assure long-term disease-free survival of poor-risk patients.

Age Factors↗
PubMed1987

Definition of response and remission in children over one year of age with advanced neuroblastoma: proposition for a scoring system.

A two-step evaluation system is proposed to analyze the results of therapy for stage IV neuroblastoma in children over 1 year of age. Since most protocols consist of first-line chemotherapy followed by surgery and often high-dose chemotherapy with bone marrow rescue, "response" should assess the effect of chemotherapy alone and "remission" indicate the status after an attempt to remove the primary tumor. A scoring system is proposed for both steps. The comparability of different studies depends on the use of such common criteria to define patient groups and treatment results.

Adolescent↗
PubMed1986

Chromosomal abnormalities in human retinoblastoma. A review.

In part because of an association between the tumor and the constitutional chromosome 13q deletion syndrome and the finding of 13q deletions or monosomy 13 in retinoblastoma cells from individuals with normal constitutional karyotypes, chromosome 13q is postulated to contain a gene responsible for tumorigenesis in retinoblastoma. A review of the cytogenetics of retinoblastoma (incorporating an analysis of five previously unpublished cases and 77 cases from the literature) revealed recurrent abnormalities (in addition to those involving number 13, 21% of cases) that included: additional copies of 1q material (44%), isochromosome (6p) (45%), monosomy 16 (18%), marker 1p+ (13%), and homogeneously staining regions and double minutes (9%). Possible roles for these chromosome abnormalities in tumor development are discussed.

Alleles↗
PubMed1986

Familial neuroblastoma. Case reports, literature review, and etiologic considerations.

The phenomenon of familial neuroblastoma is discussed in the context of case reports describing disseminated neuroblastoma in two of three half-brothers who share a common unaffected mother and who each have a different father. This family's cytogenetics proved to be unremarkable; also, the mother's peripheral blood DNA did not show tumorigenic capacities in transfection-nude mice experiments. An analysis of reported cases permits an updated examination of the clinical features of this entity and defines the limits of genetic counseling of families of all neuroblastoma patients. Multiple primaries are a hallmark of familial neuroblastoma. Most diagnoses are made in the first 18 months of life and at ages that fall within 12 months of the age of diagnosis of the other affected family member. Difficulties in determining the incidence and penetrance of an inherited susceptibility to neuroblastoma derive from undiagnosed tumors that have undergone regression or spontaneous maturation to benign ganglioneuroma, as well as from early deaths or long-term treatment complications that preclude reproduction and multigenerational pedigrees. Nevertheless, the risk of neuroblastoma in siblings or offspring of the large majority of persons with neuroblastoma appears to be less than 6%. Recent observations concerning chromosomal aberrations and oncogenes in embryonal malignancies are presented in an integrated model of tumorigenesis that corresponds to clinical experience.

Abdominal Neoplasms↗
PubMed1986

L-phenylalanine mustard-dianhydrogalactitol and hyponatremia.

The incidence of hyponatremia in 34 patients following administration of high-dose L-phenylalanine mustard (L-PAM) and dianhydrogalactitol (DAG) was determined. Two consecutive daily levels of 133 mEq/l or less were observed in 12 patients. These episodes coincided with the advent of diarrhea about 10-12 days after drug administration. The hyponatremia was not due to the syndrome of inappropriate antidiuretic hormone secretion.

Diagnosis, Differential↗
PubMed1985

Metastatic neuroblastoma and testicular involvement.

Neuroblastoma metastatic to the testes is thought to be an extremely rare event and is therefore not routinely considered in the evaluation of neuroblastoma patients. A review of metastatic sites in a series of neuroblastoma patients, however, revealed 11 cases with testicular involvement. Analysis of these cases suggests that the phenomenon may not be uncommon in a subset of neuroblastoma patients, namely, male patients with infra-diaphragmatic primaries and advanced-stage disease. Because the testes constitute a sanctuary site for tumor cells, occult testicular involvement may play a role in the relapse of patients judged to be in complete remission. Accordingly, it is proposed that in the above group of patients special diagnostic attention should be directed at the scrotal contents and, if testicular involvement is detected, orchiectomy or local irradiation should be considered.

Adolescent↗
PubMed1985

Human neuroblastoma cells and 13-cis-retinoic acid.

To a limited extent, we corroborated a previous report of human neuroblastoma sensitivity to 13-cis-retinoic acid. Seven cultured human neuroblastoma, two primitive neuroectodermal tumor, and one melanoma cell line were exposed to 0.001 to 10.0 microM 13-cis-retinoic acid for six to fourteen days. The neuroblastoma cell line, SK-N-DZ, was the only cell line lysed by all concentrations of 13-cis-retinoic acid. The other cell lines were refractory to concentrations as high as 10 microM. Increased cell process formation was observed in three neuroblastoma, SK-N-SH, SK-N-BE, SK-N-LE, and one melanoma cell line. We conclude that sensitivity to 13-cis-retinoic acid is unevenly distributed among histogenetically similar tumors from different patients.

Cell Line↗