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R J Packer

Publications and source records attributed to R J Packer.

At least 163 records · Page 9Linked to original sources
PubMed1987

Quality of life in children with primitive neuroectodermal tumors (medulloblastoma) of the posterior fossa.

We reviewed our experience in 43 consecutive patients with primitive neuroectodermal tumors (medulloblastoma), PNET (MB), treated between 1975 and 1984, to characterize their quality of life and identify factors which impacted on long-term function. Twenty-four of forty-three (56%) of children are alive and free of disease, a median of 4.5 years after diagnosis. The quality of life was analyzed for the 24 long-term survivors. 79% (19 of 24) were functioning well in everyday activities. The median full-scale intelligence quotient (FSIQ), obtained a median of 3.5 years after diagnosis for those tested (n = 17) was 97, with all but 3 (12%) of the patients functioning in the normal range. Specific learning, memory and fine-motor disabilities were found in over one half of patients. Factors associated with poorer performance and lower FSIQ included preoperative obtundation, the need for a permanent shunt, younger age at diagnosis, and a complicated postoperative course. It is concluded that (1) the majority of long-term survivors have 'normal' intellectual function, but may have specific intellectual and academic disabilities, and (2) preoperative and postoperative factors strongly impact on the quality of life of survivors.

Adolescent↗
PubMed1987

Neoadjuvant chemotherapy for newly diagnosed germ-cell tumors of the central nervous system.

A neoadjuvant (preradiotherapy) chemotherapy regimen consisting of either cyclophosphamide alone (60 to 80 mg/kg) or a modified multidrug regimen (vinblastine, bleomycin, cyclophosphamide, and cisplatin) was administered to 15 newly diagnosed patients with histologically confirmed, fully staged, primary germ-cell tumors (GCT's) of the central nervous system (CNS). There were 11 patients with germinomas and four with non-germinoma malignant GCT's. There were six females and nine males, whose median age was 13 years (range 4 months to 24 years). Seven germinoma patients (64%) had disseminated disease. For the germinoma patients, the subsequent radiotherapy dose was modified based on the response to the neoadjuvant chemotherapy, and craniospinal radiotherapy was given only to those with disseminated CNS disease at diagnosis. Ten of the 11 germinoma patients had complete disappearance of all evaluable disease after two courses of chemotherapy (cyclophosphamide in eight and multidrug in three) and one had a partial response. The planned dose of radiotherapy to the primary tumor was reduced from 5500 to 3000 rads, and the craniospinal dose was lowered from 3600 to 2000 rads. Ten patients remain in continuous disease-free remission 20+ to 89+ months after diagnosis (median follow-up period 47 months). All four patients with non-germinoma GCT's received the multidrug regimen, and two fo three patients with evaluable disease had a partial response. High-dose regional and craniospinal radiotherapy was administered thereafter, but only two patients remain in their first remission. Previously untreated germinoma is a highly chemosensitive disease and the neoadjuvant treatment strategy permits the identification of active chemotherapy regimens in newly diagnosed patients. Patients who have complete responses to neoadjuvant chemotherapy tolerate a significant radiotherapy dose reduction without compromising long-term survival, thereby allowing a reduction of some of the late effects of therapeutic radiation. Germinomas tend to disseminate early in the course of the disease and a pre-therapy staging evaluation permits individualized radiotherapy treatment planning.

Adolescent↗
PubMed1986

Magnetic resonance imaging in the evaluation of treatment-related central nervous system damage.

Neurologic and neuropsychologic treatment related sequelae are increasingly encountered in children with cancer, but conventional means of neurologic investigation are insensitive to the presence and extent of damage. Magnetic resonance imaging (MRI) has shown brain damage not demonstrable by other means of investigation. For this reason, 11 children with cancer and with nontumor-related neurologic dysfunction were studied on a 1.5 Tesla MRI unit. All had concurrent computed tomography (CT). MRI abnormalities were seen in all (100%) patients. In 10 of 11 patients, abnormalities were of greater extent on MRI than on CT. White matter changes were frequently seen on MRI without corresponding CT abnormality. Those patients with the most severe forms of neurologic compromise had the most extensive changes on MRI. Focal neurologic findings correlated well with regions of focal signal change. Milder forms of neurologic compromise occurred in patients with definite, but less extensive, periventricular and/or subcortical change on MRI. MRI is more sensitive than CT in demonstrating treatment-related neurologic damage in children with cancer, and the type of change seen on MRI seems to correlate well with the type and severity of neurologic dysfunction present.

Adolescent↗
PubMed1986

Prognostic factors in pediatric brain-stem gliomas.

The clinical, computerized tomography (CT), and histological findings from 84 children with brain-stem gliomas were reviewed to determine whether any of these features correlated with outcome. Clinical data were available from all children, CT data from 62 children, and biopsy data from 54 children. Actuarial life tables were constructed for each clinical, CT, and histological feature and the differences between these were analyzed. The period of survival was significantly shorter in children who presented with cranial nerve palsies (p less than 0.0001), and such children were more likely to have malignant tumors. Two CT features correlated with a significantly decreased survival time: a hypodense tumor prior to contrast administration and a tumor that involved the entire brain stem. Tumor enhancement was not associated with any alteration in survival times. Children with tumor biopsies that were histologically benign survived significantly longer than those whose tumors were malignant (p less than 0.0001). The histological feature associated with the poorest survival time was the presence of mitoses; features associated with the best prognosis were Rosenthal fibers and calcification. The data indicate that brain-stem gliomas are not a homogeneous group of tumors as far as their clinical, CT, and pathological features are concerned. These features may be useful in assessing prognosis and in developing future treatment protocols.

Brain Neoplasms↗
PubMed1986

Magnetic resonance imaging of spinal cord disease of childhood.

Correct diagnosis of spinal cord disease in childhood is often delayed, resulting in irreversible neurologic deficits. A major reason for this delay is the lack of a reliable means to noninvasively visualize the spinal cord. Magnetic resonance imaging (MRI) should be useful in the evaluation of diseases of the spinal cord. A 1.5 Tesla MRI unit with a surface coil was used to study 41 children, including eight patients with intrinsic spinal cord lesions, eight patients with masses compressing the cord, 12 patients with congenital anomalies of the cord or surrounding bony structures, three patients with syrinxes, and three patients with vertebral body abnormalities. Intrinsic lesions of the cord were well seen in all cases as intrinsic irregularly widened, abnormally intense cord regions. MRI was helpful in following the course of disease in patients with primary spinal cord tumors. Areas of tumor were separable from syrinx cavities. Extrinsic lesions compressing the cord and vertebral body disease were also well visualized. Congenital anomalies of the spinal cord, including tethering and lipomatous tissue, were better seen on MRI than by any other radiographic technique. MRI is an excellent noninvasive "screening" technique for children with suspected spinal cord disease and may be the only study needed in many patients with congenital spinal cord anomalies. It is also an excellent means to diagnose and follow patients with other forms of intra- and extraspinal pathology.

Adolescent↗
PubMed1986

Incidence, presentation, and outcome of spinal cord disease in children with systemic cancer.

During a 40-month period, in 24 of 643 (4%) newly diagnosed patients with systemic cancer younger than 18 years of age (range: 3 months to 17 years) spinal cord disease developed. Patients with spinal cord disease included 21 children with metastatic spinal cord compression, two with treatment-related transverse myelopathies, and one with an anterior spinal artery stroke. Spinal cord disease occurred in 13 of 102 children (12%) with sarcomas, six of 82 (7%) with neuroblastomas, and four of 94 (4%) with lymphomas. Spinal cord compression occurred as the presenting sign of malignancy in six children (four with sarcomas and two with lymphomas). In the remaining 15 patients, cord compression occurred a median of 13 months after initial diagnosis, and in four patients it occurred at the time of first relapse. Symptoms of metastatic cord compression included back pain in 17 patients (80%), weakness in 14 (67%), sphincter dysfunction in 12 (57%), and sensory abnormalities in three (14%). Findings on plain radiographs of the spine were abnormal in only seven of 20 patients with cord compression, and myelography was needed to differentiate compression from other causes of spinal cord disease. Treatment included high-dose corticosteroids followed by operation (seven patients) or radiotherapy (14 patients). After treatment, nine of 15 nonambulatory patients became ambulatory, and five of 10 incontinent patients regained sphincter control. None of the patients with nonmetastatic spinal cord disease had a satisfactory outcome.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1985

Magnetic resonance imaging in the evaluation of intracranial tumors of childhood.

Magnetic resonance imaging (MRI) is a noninvasive imaging technique that demonstrates intracranial anatomy without the use of ionizing irradiation and intravenous contrast agents. Image quality is dependent on various factors, including field strength, scanning sequence, and imaging time. Although there is currently no concensus as to how to visualize intracranial lesions optimally, MRI has already been shown to be sensitive in the detection of brain tumors. It can detect many different types of tumors; however, its specificity is unclear. Intracranial tumor extent is extremely well-demonstrated by MRI. The advantages and disadvantages of MRI compared with computerized tomography are reviewed.

Brain Neoplasms↗
PubMed1985

Oligodendroglioma of the posterior fossa in childhood.

Oligodendrogliomas are uncommon intracranial tumors of childhood, especially when these tumors arise in the posterior fossa. Oligodendrogliomas are usually treated with local radiation therapy. The authors report four children, median age 7.5 years, cared for over a 7-year period, who had oligodendrogliomas (all histologically malignant) of the cerebellar region. Three patients received local radiation therapy and all had recurrent disease at a median of 11 months posttreatment outside their radiation field; at the time of relapse, disease at the primary tumor site was stable. One child treated with craniospinal and local radiation therapy is disease-free 15 months after diagnosis. These results suggest that oligodendrogliomas of the posterior fossa should be considered potentially malignant lesions and treated with local plus presymptomatic craniospinal radiation therapy.

Adolescent↗
PubMed1985

Leptomeningeal dissemination of primary central nervous system tumors of childhood.

Presymptomatic craniospinal radiation therapy improves the rate of survival for children with brain tumors, which frequently metastasize to the leptomeninges. Radiotherapy may cause neurological damage and should be used only in patients considered to be at highest risk for leptomeningeal dissemination (LMS) at either the time of initial diagnosis or onset of disease relapse. We reviewed 314 consecutive patients with brain tumors to determine the incidence, timing, and importance of LMS. LMS occurred in 60 (19%) children. LMS occurred before diagnosis in 30 patients, as the only site of relapse or simultaneously with local first disease recurrence in 17 patients, and after local disease recurrence in 13 patients. Children with primitive neuroectodermal tumors, anaplastic gliomas, and ependymomas most frequently had LMS. Patients with primitive neuroectodermal tumors and posterior fossa anaplastic gliomas frequently had LMS before diagnosis or at the onset of relapse, whereas patients with ependymomas had LMS after local disease relapse. Both myelography and cerebrospinal fluid cytological examination are required to diagnose LMS.

Arachnoid↗
PubMed1985

Brain stem necrosis after preradiation high-dose methotrexate.

Both cranial radiation therapy (RT) and high-dose systemic methotrexate (MTX) are used to treat intracranial neoplasmas, but both may cause neurologic damage. MTX may be less neurotoxic if given before rather than after radiotherapy. We cared for a 5-year-old girl with a pineocytoma who had progressive brain stem dysfunction 4 months after MTX therapy, followed by local radiation therapy. CT studies were consistent with radiation necrosis that was confirmed at autopsy. MTX used in conjunction with cranial irradiation can result in severe neurotoxicity, even if the drug is given first.

Brain Diseases↗
PubMed1985

Brainstem gliomas of childhood: magnetic resonance imaging.

We compared magnetic resonance imaging (MRI) and CT on 16 children with brainstem gliomas. MRI demonstrated masses of decreased signal intensity, which enlarged and distorted brainstems in all patients with active disease and showed brainstem abnormalities in 21 of 23 studies (91%). In one-half of the patients, MRI showed more extensive disease than did CT. Exophytic portions of tumors were shown well on MRI. MRI was more sensitive than CT in demonstrating disease relapse.

Adolescent↗
PubMed1985

Discrepancy between computed tomography and magnetic resonance imaging in a case of medulloblastoma.

In a 2-year-old girl with signs and symptoms of a posterior fossa tumor, the computed tomographic scan showed what appeared to be a brain stem glioma. However, magnetic resonance imaging (MRI) demonstrated the lesion to be extrinsic to the brain stem. Posterior fossa exploration disclosed a medulloblastoma filling the 4th ventricle. This discrepancy in imaging techniques points out the usefulness of MRI in the evaluation and treatment of posterior fossa lesions.

Brain Stem↗
PubMed1985

Chiasmatic optic glioma treated with chemotherapy. A preliminary report.

Chiasmatic optic glioma is a rare tumor with an erratic natural history, usually seen in young children. A prior study from this institution demonstrated that these lesions were frequently lethal, despite initial clinical stabilization following radiation therapy, and that visual, intellectual, and late endocrinological disabilities were prevalent. A novel approach was developed in 1977, when an initial clinical response to vincristine was recorded in a child with a recurrent optic glioma. Since then, all children with recurrent optic glioma and all children aged 6 years old and under with newly diagnosed optic glioma have been offered a program of initial therapy with vincristine and actinomycin D for six cycles over 18 months. The four children with recurrent tumor who were treated with that regimen remain clinically stable 13 to 115 months after chemotherapy. Twelve children (eight under 24 months old) with newly diagnosed optic glioma have been treated with this program, and three are still on therapy. Four developed progression while on therapy, and five remain stable from 1 to 60 months posttherapy. The four children who developed progressive disease have been treated with radiation therapy and remain stable. Six of the 12 children showed shrinkage of their tumor on computerized tomography while receiving chemotherapy. This program may serve as an alternative to initial radiation therapy in young children.

Child, Preschool↗
PubMed1985

Cerebrovascular accidents in children with cancer.

During a 4-year period, 26 children with systemic malignancies suffered cerebrovascular accidents. These occurred in 17 patients with lymphoreticular malignancy and nine patients with solid tumors. They were the presenting signs of malignancy in three patients and were the direct cause of death in six. Cerebrovascular accidents were directly related to disseminated intravascular coagulation in eight patients, to chemotherapy in eight patients, to metastatic tumor in three patients, to thrombocytopenia in three patients, and to fungal meningitis in one patient. All patients with disseminated intravascular coagulation had leukemia and at times, cerebrovascular thrombosis predated systemic or laboratory evidence of disseminated intravascular coagulation. This review indicates that four major syndromes are apparent in children with cancer: vascular thrombosis associated with disseminated intravascular coagulation, acute arterial or sagittal sinus thrombosis secondary to L-asparaginase in children with leukemia, acute neurologic dysfunction in patients with osteogenic sarcoma treated with high-dose methotrexate, and obtundation, seizures, and focal neurologic deficits in patients with neuroblastoma metastatic to the torcular region. Although elevated WBC counts and thrombocytopenia occur frequently in children with cancer, in themselves they uncommonly result in strokes. It is concluded that cerebrovascular accidents are a relatively frequent cause of acute neurologic compromise in children with cancer and that certain types of malignancies and their treatment predispose patients to this complication.

Acute Disease↗
PubMed1985

Magnetic resonance imaging of lesions of the posterior fossa and upper cervical cord in childhood.

Magnetic resonance imaging (MRI) promises to be an effective, noninvasive means of visualizing intracranial pathology. It should be especially useful in the evaluation of posterior fossa and cervical spinal cord disease of childhood; computed tomographic (CT) evaluation is frequently suboptimal in this region. MRI results are reported for 46 consecutively seen children with posterior fossa and/or cervical spinal cord disease (28 had brain malignancies; seven had congenital anomalies; three had cerebrovascular accidents). MRI was performed primarily by the partial saturation on a .12 Tesla resistive proton unit. All patients underwent concurrent CT evaluation. MRI demonstrated abnormalities in 96% of scans in patients with structural CNS disease (48 of 50). CNS malignancies were visualized in 100% (28 of 28) of children studied. MRI was especially useful in demonstrating the full extent of infiltrating gliomas and the anatomic location of other mass lesions. MRI frequently demonstrated disease to be more extensive than seen on CT. MRI was more sensitive than CT in documenting response to treatment and disease relapse in patients with infiltrating tumors. Cystic regions within tumors were poorly seen on MRI. Congenital anomalies were demonstrated in all patients evaluated and were better delineated using MRI than CT. MRI is sensitive in the evaluation of posterior fossa and cervical spinal cord disease of childhood and it has obvious advantages over CT; however, its specificity in such evaluations has yet to be proven.

Brain↗
PubMed1985

Pediatric phase I trial and pharmacokinetic study of tiazofurin (NSC 286193).

Tiazofurin (2-beta-D-ribofuranosylthiazole-4-carboxamide), a new nucleoside antimetabolite, was evaluated in a phase I trial involving children with refractory cancers. The drug was administered i.v. as a 10-min infusion daily for 5 consecutive days repeated at 3-week intervals. The dose ranged from 550 to 3300 mg/sq m/day. Seventeen patients received 23 courses and were evaluable for toxicity. The maximally tolerated dose was 2200 mg/sq m/day. The major dose-limiting toxicities were nonhematological. Neurotoxicity, including headache, drowsiness, and irritability, was common and was the principal dose-limiting toxicity at the higher doses. Severe myalgias were also dose limiting in one patient. Other side effects were mild, reversible elevations in serum transaminases; nausea, vomiting, and diarrhea; mild hypertension; dysphagia; and exfoliative dermatitis of the hands and feet. Myelotoxicity was not significant. The pharmacokinetics of tiazofurin was studied in 16 patients. Plasma disappearance was triphasic with half-lives of 9.7 min, 1.6 h, and 5.5 h. Clearance was dose related, ranging from 120 ml/min/sq m at 550 mg/sq m/day to 70 ml/min/sq m at 3300 mg/sq m/day. The primary route of elimination was renal with 85% of the drug recoverable in the urine as the parent compound in the 24 h following administration.

Adolescent↗