Biomedical subjects

L Kun

Publications and source records attributed to L Kun.

At least 37 records · Page 2Linked to original sources

PubMed1993

Pre-irradiation chemotherapy and hyperfractionated radiation therapy 66 Gy for children with brain stem tumors. A phase II study of the Pediatric Oncology Group, Protocol 8833.

BACKGROUND: Fewer than 20% of children with intrinsic brain stem tumors survive longer than 2 years. Although some improvement has been noted in recent trials using higher doses of hyperfractionated radiation therapy (HRT), the feasibility of pre-irradiation chemotherapy has not been explored in these patients with poor prognosis. METHODS: Between February 1988 and March 1989, 37 patients were entered onto a Phase II Pediatric Oncology Group study for evaluating the feasibility, response, and toxicity of treating children with high-risk brain stem tumors with chemotherapy followed by HRT (66 Gy). Chemotherapy consisted of four cycles of cisplatin (100 mg/m2) plus cyclophosphamide (3 g/m2). RESULTS: Of 32 eligible patients, 65% improved clinically during the first 2-3 cycles of chemotherapy; 75% of those improving were weaned from steroids. On neuroradiology review of scans before and after chemotherapy, 3 patients had partial responses (PR, > 50% shrinkage), 23 had stable disease (SD), and 6 had progressive disease (PD). The median survival was 9 months. The three patients who attained a PR on chemotherapy were among the longest survivors at 38 plus, 44 plus, and 40 months. Toxicities included profound but brief marrow suppression, transient electrolyte-renal dysfunction, and ototoxicity. Brain stem swelling from intravenous fluids caused transient deterioration in two patients. Six patients developed an unusual syndrome of transient marrow suppression after HRT. CONCLUSIONS: This study suggests that pre-irradiation chemotherapy can be successfully added to the treatment of patients with brain stem tumors with both clinical and objective responses noted, but that other agents must be identified to overcome the apparent development of drug resistance and to improve survival.

Adolescent↗

PubMed1993

A phase I study of ifosfamide given on alternate days to treat children with brain tumors.

BACKGROUND: Ifosfamide with Mesna, given every other day over a 5-day period, was evaluated in 20 children with recurrent or progressive primary brain tumors. METHODS: The patients were assigned to dosage cohorts separated on the basis of prior exposure to cisplatin (n = 10) or the absence of such exposure (n = 10). The initial dose in each treatment arm was 2133 mg/m2 every other day for three doses, which represented 80% of the total dose delivered in our prior study of ifosfamide given daily over 5 days. The dose was escalated by 20% in each of the two subsequent cohorts (2560 mg/m2 and 3072 mg/m2 every other day for three doses). RESULTS: The hematologic toxicity was dose limiting. Prior exposure to cisplatin did not seem to increase the hematologic toxicity. The most frequent and significant metabolic disturbance was hyponatremia, resulting in self-limited seizure activity in three patients. This complication was prevented in subsequent patients by changing the post-ifosfamide hydration fluids from 5% dextrose in quarter normal saline to 5% dextrose in normal saline. CONCLUSIONS: Although no child achieved a complete response, the activity of ifosfamide was demonstrated for a variety of tumors. The recommended dose of ifosfamide in a Phase II study for brain tumors is 3000 mg/m2 given with Mesna every other day for three doses.

Adolescent↗

PubMed1993

Acute hypersensitivity reactions to etoposide in a VEPA regimen for Hodgkin's disease.

PURPOSE: We report an unexpectedly high incidence of hypersensitivity to etoposide among 45 patients with newly diagnosed Hodgkin's disease treated with vinblastine, etoposide, prednisone, and doxorubicin (VEPA) plus radiation. PATIENTS AND METHODS: Twenty-three of 45 patients (51%) had one or more acute hypersensitivity reactions to etoposide administration. The 23 patients were 8 to 18 years of age (median, 15 years); 12 were males. Four patients had experienced prior allergic reactions to antibiotics or intravenous contrast media. RESULTS: Hypersensitivity reactions followed the first or second dose of VEPA in most cases. The reactions occurred at a median time of 5 minutes (range, 3 to 120) from the start of the etoposide infusion. Fifteen patients reacted early (within 10 minutes), four midway through the infusion, and four after completion of the infusion. Signs and symptoms included flushing, respiratory problems, changes in blood pressure, and abdominal pain with or without nausea and vomiting. Respiratory problems included dyspnea, chest pain/tightness, bronchospasm, and cyanosis. Symptoms were alleviated by discontinuing the etoposide infusions and administering diphenhydramine and/or hydrocortisone; epinephrine was required to reverse bronchospasm in three cases. All 23 patients recovered without adverse sequelae and were rechallenged with etoposide. Fifteen patients tolerated subsequent etoposide infused at a slower rate, with antihistamine and/or corticosteroid premedication; five had recurrent hypersensitivity despite these measures. Three of these five developed similar symptoms when teniposide was substituted for etoposide. Three patients who had isolated episodes of hypotension on completion of the etoposide infusion successfully received subsequent infusions without premedication or change in infusion rate or concentration. CONCLUSION: Despite this unexpectedly high incidence of hypersensitivity among Hodgkin's disease patients treated with etoposide, rechallenge with the drug was successful in 78% of cases.

Acute Disease↗

PubMed1993

Anti-pan T lymphocyte ricin A chain immunotoxin (H65-RTA) and methylprednisolone for acute GVHD prophylaxis following allogeneic BMT from HLA-identical sibling donors.

Six patients (five children < or = 12 years old and one young adult) underwent allogeneic BMT (not T lymphocyte-depleted) from sex-matched HLA-identical siblings. GVHD prophylaxis consisted of methylprednisolone (30 mg/m2) and anti-pan T lymphocyte ricin A chain immunotoxin (H65-RTA) (0.1 mg/kg) administered daily for 12 consecutive doses. H65-RTA was initiated at day +5 (n = 4) or day +2 (n = 2). All patients engrafted. Despite receiving the planned GVHD prophylaxis, all patients developed moderate to severe acute GVHD; five patients developed Grade III/IV GVHD. Four patients died 34 to 78 days post-transplant; GVHD was a contributory cause of death in each case. H65-RTA as used in this study was ineffective for the prophylaxis of acute GVHD.

Adult↗

PubMed1992

Treatment of childhood germ cell tumors. Review of the St. Jude experience from 1979 to 1988.

BACKGROUND: The outlook for patients with germ cell tumors was poor before the advent of effective chemotherapy. The authors assessed the outcome of treatment with multiagent chemotherapy (with or without radiation therapy) in children treated for germ cell tumors at St. Jude Children's Research Hospital (SJCRH). METHODS: Sixty children with germ cell tumors were treated between January 1979 and June 1988. Postsurgical treatment was based on tumor site, stage, and histology. Most patients received chemotherapy with vincristine, actinomycin-D, and cyclophosphamide (VAC), or a modified Einhorn regimen (cisplatin, bleomycin, and vinblastine [PVB]); in the absence of response to initial therapy, patients received alternating courses of VAC and PVB (VAC/PVB regimen). Exceptions were patients with Stage I testicular tumors (observation only) and ovarian germinomas (Stage I tumors measuring less than 10 cm, observation only; tumors larger than 10 cm or Stage II-III disease, radiation only; and Stage IV disease, VAC plus radiation). RESULTS: The estimated 5-year survival is 100% for patients with Stage I disease (n = 18), 87% for patients with Stage II (n = 8), 72% for Stage III (n = 25), and 56% for Stage IV (n = 9). Patients with testicular tumors of any stage or with Stage I-II ovarian tumors had 100% 5-year survival. Extragonadal tumors responded poorly to VAC alone with recurrent or progressive disease in eight of nine patients. Treatment for those tumors was changed to alternating courses of VAC and PVB, which failed in only one of seven patients. Nine of 19 patients with advanced ovarian tumors had disease recurrence with VAC; these patients then received PVB, which was effective in four cases. CONCLUSIONS: For patients with advanced germ cell cancers, intensification of therapy or the development of new approaches is necessary. In contrast, future trials in children with limited stage should focus on reducing acute and long-term toxicities.

Adolescent↗

PubMed1992

Inhibition by glaucocalyxin A of aggregation of rabbit platelets induced by ADP, arachidonic acid and platelet-activating factor, and inhibition of [3H]-PAF binding.

Glaucocalyxin A is a new diterpenoid isolated from the ethereal extract of the leaves of Rabdosia japonica (Burm f) Hara var glaucocalyx (Maxim) Hara (Labiatae) collected in the northeastern China. When it was incubated with washed rabbit platelets, glaucocalyxin A inhibited ADP- or arachidonic acid-induced platelet aggregation with IC50 values of 4.4 mumol/l, 14.1 mumol/l respectively. Glaucocalyxin A also inhibited PAF-induced aggregation of rabbit platelets which were refractory to ADP and arachidonic acid with an IC50 value of 13.7 mumol/l. Analysis of [3H]-PAF binding showed that glaucocalyxin A prevented [3H]-PAF binding to intact washed rabbit platelets with an IC50 value of 8.16 mumol/l, which was consistent with its inhibition of PAF-induced platelet aggregation.

Adenosine Diphosphate↗

PubMed1992

Neuropsychological status of children treated for brain tumors: a critical review and integrative analysis.

The literature on the neuropsychological status of children with primary brain tumors was reviewed to identify English-language publications reporting the results of standardized, quantitative measures of patient function. The 22 studies that met these review criteria, representing 544 patients, were evaluated to assess the relationship between traditional risk factors (age at diagnosis, tumor location, radiation therapy, and time since completion of treatment), as well as subsequent intellectual development, academic achievement, psychosocial adjustment, and neuropsychological status. The impact of other potentially salient factors, such as seizures and sensory and motor deficits, was evaluated when possible. Despite inconsistent reporting of demographic and treatment-related effects across studies which precluded formal meta-analysis, we were able to confirm the primary importance of radiation therapy volume and age at treatment on IQ. No effects were detected for tumor location. Younger children treated with cranial (whole brain) irradiation showed a 14-point deficit in IQ as compared with their older counterparts. No significant differences were noted between older children receiving local or cranial irradiation, although both groups had IQ levels 12-14 points lower than those not irradiated. The high-risk groups identified in this study require increased clinical surveillance. Definitive evaluation of potential risk factors for neuropsychological impairment will depend on more complete reporting of relevant patient characteristics and interinstitutional studies.

Adolescent↗

PubMed1992

Serum lactate dehydrogenase in childhood neuroblastoma. A Pediatric Oncology Group recursive partitioning study.

On the basis of an extensive recursive partitioning analysis of 668 patients with newly diagnosed neuroblastoma registered on Pediatric Oncology Group (POG) studies between October 1981 and May 1987, four major subsets of patients were created. Important prognostic factors included the patient's stage of disease, age, and level of serum lactate dehydrogenase (LDH). After adjusting for these factors, no other clinical prognostic factors were significant. The implications for protocol design are that (a) fine tuning of current therapy should be sought for the two favorable disease patient subsets, while (b) novel aggressive therapies are needed for the two unfavorable disease patient subsets where the overwhelming majority are dying. This article may serve as a model for others investigating prognostic factors. The data were divided into two subsets: one was used for an exploratory analysis; the other was used to confirm the exploratory findings. Despite spite the large number of statistical tests performed, the likelihood that the findings can be attributed to chance can be dismissed as virtually zero.

Adolescent↗

PubMed1992

Ifosfamide plus etoposide in newly diagnosed Ewing's sarcoma of bone.

PURPOSE: We assessed the activity of ifosfamide plus etoposide against newly diagnosed Ewing's sarcoma of bone by administering this drug pair before standard induction therapy (the upfront window approach). PATIENTS AND METHODS: Twenty-six children and adolescents with newly diagnosed, previously untreated Ewing's sarcoma of bone were enrolled onto this pilot study (EW-87). Eighteen were at a higher risk of treatment failure, with a primary tumor size of more than 8 cm or metastases at diagnosis. Window therapy with ifosfamide (1.6 g/m2/d with mesna uroprotection) and etoposide (100 mg/m2/d) was given in three 5-day cycles at 21-day intervals. Responses were evaluated clinically and radiologically. Subsequent induction therapy comprised three cycles of cyclophosphamide and doxorubicin. Radiation therapy was the primary local control modality; surgery was limited to biopsy or resection of expendable bones. After the local control phase, alternating courses of vincristine plus dactinomycin, ifosfamide plus etoposide, and cyclophosphamide plus doxorubicin were given as maintenance therapy. RESULTS: There were four complete responses and 21 partial responses to ifosfamide/etoposide window therapy (overall response rate 96%; 95% confidence interval [CI], 80% to 99%). Disease progression was observed in four patients during the cyclophosphamide/doxorubicin phase. Chemotherapy was well tolerated; only 16% (20 of 125) of all ifosfamide/etoposide window and maintenance cycles resulted in hospitalization for fever and neutropenia. Two patients developed chemotherapy-induced cystitis. CONCLUSIONS: The combination of ifosfamide and etoposide is highly active against previously untreated Ewing's sarcoma and generally is well tolerated. The ultimate impact of these two agents on outcome will be determined in randomized multicenter studies.

Adolescent↗

PubMed1991

Hyperfractionated radiation therapy in brain stem tumors. Results of treatment at the 7020 cGy dose level of Pediatric Oncology Group study #8495.

Between May 1986 and February 1988, 57 patients were accrued to the second dose level of a Phase I/II Pediatric Oncology Group (POG) study exploring the use of hyperfractionated radiation therapy (HRT) in children with high-risk brain stem tumors. Local fields were treated with fraction sizes of 117 cGy given twice daily, with a minimum interfraction interval of 6 hours, to a total dose of 7020 cGy in 60 fractions over 6 weeks. Information regarding clinical status during HRT was available for 55 patients (44 [80%] improved, 6 remained stable, and 5 deteriorated). Results of initial and follow-up computed tomography (CT) scan and/or magnetic resonance imaging (MRI) were available for review for 52 patients. One patient had a complete response (CR) to treatment, 3 had a partial response (PR) (more than 50% response), and 40 remained stable, for a total response rate (CR + PR + stable) of 77%. Median time to disease progression was 6 months. Median survival time was 10 months. Survival rate was 39.6% (standard error [SE] = 6.6%) at 1 year and 23% (SE = 5.8%) at 2 years. Complications of treatment included an enhanced skin reaction in six patients and otitis media and/or externa in nine. One patient bled into tumor shortly after completion of HRT, and three had intralesional necrosis. Five patients continued taking steroids for protracted periods in the face of improved clinical and/or radiologic findings. Complications related to the use of steroids included opportunistic infections, impaired glucose tolerance, hypertension, osteoporosis, and significant mood changes. In no patient was there evidence of any late injury attributable to HRT. When compared with results of treatment with HRT at a lower dose level (6600 cGy), there appears to be a trend toward improved survival at 7020 cGy despite a less favorable patient population at the higher dose level. A second dose escalation to 7560 cGy in 60 fractions over 6 weeks has been implemented as planned.

Adolescent↗

PubMed1991

The role of second-look surgery in the management of advanced germ cell malignancies.

The need for second-look surgery after chemotherapy in children with advanced germ cell tumors is controversial, particularly when levels of the tumor markers alpha-fetoprotein (AFP) or beta-human chorionic gonadotropin (beta HCG) are elevated at diagnosis. The authors evaluated the outcome of second-look surgery in relationship to tumor marker status in 27 patients with Stage III to IV disease who had completed four courses of chemotherapy. Markers were elevated at diagnosis in 19 patients. After chemotherapy, markers normalized in 12 of these patients. Second-look surgery confirmed complete response (CR) in these 12 patients, two of whom had residual masses on computed tomography (CT) scan (mature teratoma and necrotic tumor). The AFP decreased but did not normalize in seven patients; five had residual disease at second look and the other two later developed measurable disease. Of the eight patients with normal AFP at diagnosis, second look confirmed clinical CR in four. The other four patients had CT evidence of residual masses: surgery showed necrotic tissue in two cases, mature glial elements in one, and mature teratoma with glial elements in one. Thus second-look surgery added no information for treatment planning in children with elevated tumor markers at diagnosis and might best be reserved for patients without tumor markers at diagnosis and residual masses on CT scan, and those with persistent elevation of tumor markers and potentially resectable residual disease. Because of the possibility of small amount of residual tumor, second-look surgery may also be useful in patients whose markers normalize but who have residual masses on CT scans.

Adolescent↗

PubMed1991

Production of two human hybridomas secreting antibodies to HLA-DRw11 and--DRw8+w12 specificities.

In this study we describe the production of two human monoclonal antibodies (mAbs) HMP12 and HMP14, that recognize polymorphic HLA-DR specificities. These mAbs have been produced by hybridization of antibody-secreting Epstein-Barr virus-transformed cells with SHM-D33 human-mouse heteromyeloma. By microcytotoxicity assay HMP12 mAb was found to react with all DRw11-positive cells and HMP14 mAb with all cells bearing the DRw8 or the DRw12 specificity. Cytotoxic activity of HMP14 was completely removed after absorption with DRw8- or DRw12-positive cells and unaffected by absorption with cells carrying different DR specificities. The HLA specificity was further analyzed by cytofluorometry on mouse transfectant cells. The reactivity of the two mAbs was correlated with the presence of a particular polymorphic amino acid residue in the DR beta chain and by this approach the epitopes possibly involved in the antibody binding sites were predicted.

Amino Acid Sequence↗

PubMed1991

Impact of intensified therapy on clinical outcome in infants and children with neuroblastoma: the St Jude Children's Research Hospital experience, 1962 to 1988.

To gauge the impact of intensified therapy on the survival of infants (younger than 1 year, n = 129) and children (greater than or equal to 1 year of age, n = 275) with neuroblastoma, we analyzed the results of eight successive clinical trials comparing various combinations of antineoplastic drugs, surgery, and radiotherapy. Changes in treatment did not affect the survival of children with involved noncontiguous lymph nodes or distant metastatic disease until the combination of cisplatin and teniposide (CDDP/VM26) was added to a basic regimen of cyclophosphamide and doxorubicin (CTX/DOX). The resulting 4-year survival was 28% +/- 5% (SE) compared with 7% +/- 2% for previous treatments (P less than .001 by the log-rank test). The 4-year survival of infants with metastatic disease was improved by administering CTX/DOX to all patients, reserving CDDP/VM26 for those whose disease was resistant to the former combination: 82% +/- 6% versus 45% +/- 8% in earlier studies; P less than .001. In the subset of infants whose tumors had disseminated to bone or bone marrow at diagnosis, this therapeutic approach increased the probability of long-term survival from 48% +/- 10% to 85% +/- 9% (P = .01). The small group of children over 1 year of age with localized unresectable tumors also fared significantly better with the switch to CTX/DOX chemotherapy (4-year survival, 93% +/- 7% v 42% +/- 13%; P = .02). Multivariate analysis indicated that young age, limited-disease stage, nonadrenal primary site, and intensified treatment were independent predictors of a more favorable outcome. We conclude that substantial advances in the treatment of neuroblastoma have occurred over the past 25 years at this institution. The current overall 4-year survival probability of 57% +/- 4% compares favorably with estimates for most other common solid tumors of childhood.

Age Factors↗

PubMed1991

Nitrogen mustard, vincristine, procarbazine, and prednisone as adjuvant chemotherapy in the treatment of medulloblastoma. A Pediatric Oncology Group study.

In a randomized postoperative trial, adjuvant post-irradiation chemotherapy, consisting of nitrogen mustard, vincristine, procarbazine, and prednisone (MOPP), was tested versus radiation therapy alone for newly diagnosed medulloblastoma in patients between 1 and 21 years of age. Patients treated with irradiation plus MOPP had a statistically significant increase in overall survival rate at 5 years posttreatment compared to patients treated with radiation therapy alone (74% vs. 56%; p = 0.06, adjusted for race and gender). Although the overall study failed to show a statistically significant advantage for irradiation plus MOPP in event-free survival (p = 0.18), statistical significance was attained in children 5 years of age or older (p = 0.05). More severe hematological toxicities occurred in the group with irradiation plus MOPP; however, this hematotoxicity appeared to be tolerable and acceptable. These results suggest that patients may benefit from combined irradiation and chemotherapy following surgery for medulloblastoma.

Adolescent↗

PubMed1991

Hyperperfusion injury in IgA nephropathy.

The authors have found morphological alterations identical with hyperfiltration glomerular injury in the renal biopsies of 23 out of 100 patients with IgA nephropathy. In 15 of them the lesions were similar to the different stages of segmental glomerular hyalinosis and sclerosis with deposition of IgM and C3. At the time of renal biopsy, the serum creatinine of all except 8 patients was normal (maximally 170 mumol/1), only 13 had hypertension, and all except 2 were proteinuric. During the follow-up period (mean +/- 2Sd = 138 +/- 76 months) all of them became hypertensive. In 10 patients end-stage renal failure developed, and in another 10, serum creatinine also became elevated (range 124 - 504 mumol/1). On the basis of these data the development of focal segmental hyalinosis and sclerosis should be interpreted as a bad prognostic sign in IgA nephropathy.

Adult↗

PubMed1991

Hyperperfusion injury in IgA nephropathy.

Adult↗

PubMed1990

Local-regional non-rhabdomyosarcomatous soft tissue sarcomas of the head and neck.

Between 1962 and 1987, 112 consecutive patients were treated at St. Jude Children's Research Hospital for soft tissue sarcomas of the head and neck region; 18 of these children (16%) had histologic subtypes other than rhabdomyosarcoma. We evaluated the impact of surgery, postoperative chemotherapy, and irradiation on local control and survival in these cases. Three patients who had complete resection of tumors and received no further treatment are alive without disease at 36, 42, and 162 months. Local control was achieved in 1 of 2 patients with microscopic residual tumor and 4 of 9 patients with gross residual tumor who were treated with irradiation (2500-5040 cGy). Chemotherapy was the only postoperative treatment in three patients; only one achieved lasting local control. One patient was treated with irradiation only; his primary site showed no tumor cells at autopsy following an automobile accident. Overall, local control was achieved in 50% of patients; the disease-free survival rate at 3 years was 44%. The prognosis for patients with nonresectable tumors remains unsatisfactory because of the difficulty in securing local control. A revised therapeutic approach to these patients is presented.

Adolescent↗

PubMed1990

Treatment of meningeal relapse in childhood acute lymphoblastic leukemia: II. A prospective study of intellectual loss specific to CNS relapse and therapy.

Changes in intellectual function during the course of treatment for acute lymphocytic leukemia were studied. Twenty-four children had baseline psychological evaluations and annual reevaluations for 3-6 years postdiagnosis. Treatment in all patients included combination chemotherapy, 2,400 cGy prophylactic cranial irradiation, and intrathecal methotrexate. Central Nervous System (CNS) relapse occurred in eight of these children. It was then treated with 3,000 cGy cranial plus 1,800 cGy spinal irradiation. Patients who remained in continuous complete remission showed no decline in global intelligence quotient (IQ). Patients who experienced CNS relapse had a mean decline of 16 IQ points by 3 years postdiagnosis and the long-term survivors displayed a mean loss of 25 IQ points 5-6 years postdiagnosis. Three of the five long-term survivors of CNS relapse function within the retarded range of mental ability and require special education. The other two have learning problems and display poor academic performance relative to same-age peers. There was no association noted between age at diagnosis and ultimate loss of IQ points. This prospective study suggests that children who receive a second course of cranial irradiation for treatment of CNS relapse are at high risk for significant and progressive intellectual loss.

Antineoplastic Combined Chemotherapy Protocols↗