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A T Meadows

Publications and source records attributed to A T Meadows.

150 records · Page 9Linked to original sources
PubMedDate not supplied

Primary mediastinal large cell lymphoma in children: a report from the Childrens Cancer Group.

Malignant lymphomas arising in the mediastinum account for approximately 60% of all mediastinal tumors in children; two-thirds are non-Hodgkin's lymphomas and one-third represent Hodgkin's disease. In contrast to adults, in children mediastinal non-Hodgkin's lymphomas are usually synonymous with lymphoblastic lymphoma, and nonlymphoblastic lymphomas are rare. We describe nine children with primary mediastinal large cell lymphoma who were treated with the Children's Cancer Group protocol CCG-503, a randomized phase III protocol for disseminated nonlymphoblastic lymphoma. Histologic subclassification revealed three immunoblastic lymphomas, three multilobated large cell lymphomas, one with clear cell features, and two large noncleaved cell lymphomas. Sclerosis, of variable degrees, was seen in all tumors. Immunophenotyping revealed all tumors to be of B cell lineage. Thymic epithelial cells could be demonstrated, utilizing antibody to keratin, in two of nine patients, suggesting that some of the tumors are of thymic origin. None of the patients had central nervous system or bone marrow involvement. It appears that primary mediastinal nonlymphoblastic lymphomas in children, although much less common, are similar to those seen in adults. These tumors must be differentiated from lymphoblastic lymphoma and Hodgkin's disease, as the therapeutic approach may depend on histologic subtype. Primary mediastinal large cell lymphoma in children appears curable with aggressive treatment in the majority of patients.

Adolescent↗
PubMedDate not supplied

The effect of chemoreduction on retinoblastoma-induced retinal detachment.

BACKGROUND: Retinoblastoma with total retinal detachment traditionally has been managed with enucleation. We employed a chemoreduction protocol in an effort to reduce the tumor size to allow for focal treatment and salvage of the eye. METHODS: A prospective study was performed to assess the effects of a 2-month chemoreduction regimen of vincristine, etoposide, and carboplatin on massive retinoblastoma with total retinal detachment. RESULTS: We treated 17 eyes with total retinal detachment from retinoblastoma in 13 patients over a 14-month period. At the initial examination, the mean tumor base was 15 mm and mean thickness was 10 mm. The eyes were classified as Reese-Ellsworth group V in 16 cases (94%) and group III in one case (6%). The retina was totally detached with serous subretinal fluid in all cases. After 2 months of chemoreduction, all tumors showed a response, and the tumors decreased to a mean base of 10 mm and thickness of 5 mm. Overall, a mean of 33% decrease in base and 47% decrease in thickness was noted. The subretinal fluid had resolved completely in seven eyes (41%), leaving flat retina. In three eyes (18%), partial resolution was achieved; in seven eyes (41%), minimal resolution of the subretinal fluid at the 2-month period was noted. By last follow up, at a mean of 10 months after initiation of chemoreduction, complete resolution of the subretinal fluid occurred in 13 eyes (76%) and partial resolution of subretinal fluid occurred in four eyes (24%). CONCLUSION: Preliminary observations suggest that chemoreduction may be an important tool in the initial management of retinoblastoma, even for large tumors with total retinal detachment. Tumor shrinkage may be dramatic and subretinal fluid resolution may be complete.

Antineoplastic Combined Chemotherapy Protocols↗
PubMedDate not supplied

Risk factors for astrocytic glioma and primitive neuroectodermal tumor of the brain in young children: a report from the Children's Cancer Group.

We conducted a matched case-control study to investigate risk factors for the two most common types of brain tumors in children, astrocytic glioma and primitive neuroectodermal tumor (PNET). Since the study focused on gestational exposures, we restricted it to young children because these exposures would be expected to act early in life. Parents of 155 astrocytic glioma cases, 166 PNET cases, and controls identified by random digit dialing completed telephone interviews. Few associations occurred with the hypothesized risk factors, which were gestational exposure to alcohol, hair coloring products, farms, and substances containing N-nitroso compounds (passive smoking, makeup, incense, new cars, pacifiers, baby bottles, beer). Of the products studied that contain N-nitroso compounds, only beer was associated with a significantly increased risk of either tumor type [odds ratio (OR) for PNET = 4.0; 95% confidence interval (CI), 1.1-22.1; P = 0.04]. Elevated ORs for PNET were observed for farm residence of the mother during the pregnancy (OR = 3.7; 95% CI, 0.8-23.9; P = 0.06) and of the child for at least a year (OR = 5.0; 95% CI, 1.1-46.8; P = 0.04). Significant associations with astrocytoma were observed for mother's use of kerosene (OR = 8.9; 95% CI, 1.1-71.1; P = 0.04) and birth by Caesarean section (OR = 1.8; 95% CI, 1.1-3.2; P = 0.03). History of miscarriage was associated with a lower risk of PNET (OR = 0.5; 95% CI, 0.3-0.9; P = 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Abortion, Spontaneous↗