Biomedical subjects

M Hamre

Publications and source records attributed to M Hamre.

5 recordsLinked to original sources

PubMed1998

Permanent I-125 brain stem implants in children.

Between 1988 and 1997, 28 children have had iodine-125 implants for CNS tumors performed in our institution. Ten had stereotactic implantation in the brain stem region, and nine had the diagnosis of brain stem glioma (8 diffuse pontine, 1 midbrain tumor). Their ages ranged from 1.8 to 12 years. All patients had histological confirmation of malignancy (7 high-grade glioma, 2 low-grade glioma, 1 PNET). Diffuse pontine glioma patients received external beam radiation (50 Gy) followed by a fractionated stereotactic boost of 3 Gyx4 fractions. After 4-6 weeks, patients were reevaluated for stereotactic interstitial I-125 therapy. The planned implant dose was 82.9 Gy to the enhancing tumor (4 cGy per h). Preliminary results indicated that no surgical complications were associated with the catheter placement. Four patients have died (7-9 months from diagnosis) and four patients remain alive (5-38 months from diagnosis, median 10 months). Two autopsies confirmed the presence of progressive glioblastoma multiforme and intralesional necrosis. In one patient who received an implant alone for midbrain LGA, necrosis without tumor was found on biopsy after 36 months. He was successfully treated with hyperbaric oxygen therapy. The implementation of permanent I-125 implants appears to have a role in the management of pediatric CNS malignancy. This study confirms the results of previous reports regarding the safety of stereotactic interstitial brachytherapy in the brain stem. Tumor control for patients with high-grade brain stem glioma remains poor even with high focal radiation doses.

Brachytherapy↗

PubMed1998

Constitutional balanced translocations in alveolar rhabdomyosarcoma.

Chromosomal analysis of tumor tissue from two children with alveolar rhabdomyosarcoma revealed t(1;5)(q32;q31) and t(1;22)(q21;q11.2) in all metaphases examined, respectively. Peripheral blood lymphocytes carried the same cytogenetic abnormality as that of the tumor cells in both patients. Parental lymphocytes were karyotypically normal in the patient with t(1;22), indicating a de novo constitutional translocation, but t(1;5) was paternally inherited in the other patient. The presence of constitutional translocations in these two children might have contributed to the development of alveolar rhabdomyosarcoma.

Child↗

PubMed1997

Langerhans cell histiocytosis: an exploratory epidemiologic study of 177 cases.

There is little information available regarding epidemiologic risk factors for Langerhans cell histiocytosis (LCH). An exploratory investigation was conducted using information obtained from parents of 177 cases of LCH diagnosed before 21 years of age (median 2 years). Utilizing data available from the Children's Cancer Group, LCH cases were compared to two matched control groups including 614 patients diagnosed with a variety of childhood cancers and 318 community controls. Questionnaire data included information on demographics, prenatal and perinatal factors, complications in the neonatal period, environmental exposures, family medical history, and childhood exposures. Factors found to be statistically significantly associated with an increased risk of LCH included: maternal urinary tract infection during the index pregnancy, feeding problems during infancy, and blood transfusions during infancy. Use of supplemental vitamins was associated with a significantly decreased risk of LCH. Results from this exploratory study provide a basis for speculation on potential etiologic risk factors for LCH. Future epidemiologic investigations of LCH need to consider the presenting disease characteristics in assessing possible etiologic factors.

Adolescent↗

PubMed1994

Intraspinal Wilms' tumor metastases.

BACKGROUND: Intraspinal Wilms' tumor metastasis is rare, and is associated with a high mortality rate. METHODS: The authors reviewed the clinical course of two patients with Wilms' tumor in whom extradural metastasis developed. In addition, a review of the literature and of patients entered in the National Wilms' Tumor Studies was performed to determine the clinical presentation, treatment, and outcome of other patients with Wilms' tumor with intraspinal metastases. RESULTS: Both of the patients initially had abdominal pain without neurologic deficits. Despite therapy, paraplegia secondary to cord compression from recurrent epidural metastases developed in one patient, although a third remission has been achieved with further chemotherapy. the second patient remains in disease-free remission 25+ months after surgical resection of the extradural spinal tumor, adjuvant chemotherapy and radiation therapy, and autologous bone marrow transplantation. Review of the literature and of the patients entered in the National Wilms' Tumor Studies revealed an additional 27 patients with Wilms' tumor with this pattern of metastasis. Only four were disease-free at the time of this report. CONCLUSIONS: The authors' experience stresses the importance of early recognition and treatment of this complication of Wilms' tumor and demonstrates that intensive multimodality therapy can result in long-term disease-free remission.

Child↗

PubMed1994

Spontaneous subcutaneous emphysema.

Subcutaneous emphysema is an unusual complication of bronchiolitis. The investigators describe a patient with bronchiolitis who developed extensive subcutaneous emphysema. Despite an alarming appearance, the patient recovered with symptomatic care and observation. Review of the literature shows a multitude of causes of subcutaneous emphysema. The vast majority of cases resolve without intervention.

Bronchiolitis↗