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M M Stevens

Publications and source records attributed to M M Stevens.

At least 55 records · Page 3Linked to original sources
PubMed1990

A clinical trial of beta carotene to prevent basal-cell and squamous-cell cancers of the skin. The Skin Cancer Prevention Study Group.

BACKGROUND: Beta carotene has been associated with a decreased risk of human cancer in many studies employing dietary questionnaires or blood measurements, and it has had protective effects in some animal models of carcinogenesis. METHODS: We tested the possible cancer-preventing effects of beta carotene by randomly assigning 1805 patients who had had a recent nonmelanoma skin cancer to receive either 50 mg of beta carotene or placebo per day and by conducting annual skin examinations to determine the occurrence of new nonmelanoma skin cancer. RESULTS: Adherence to the prescribed treatment was good, and after one year the actively treated group's median plasma beta carotene level (3021 nmol per liter) was much higher than that of the control group (354 nmol per liter). After five years of follow-up, however, there was no difference between the groups in the rate of occurrence of the first new nonmelanoma skin cancer (relative rate, 1.05; 95 percent confidence interval, 0.91 to 1.22). In subgroup analyses, active treatment showed no efficacy either in the patients whose initial plasma beta carotene level was in the lowest quartile or in those who currently smoked. There was also no significant difference between treated and control groups in the mean number of new nonmelanoma skin cancers per patient-year. CONCLUSIONS: In persons with a previous nonmelanoma skin cancer, treatment with beta carotene does not reduce the occurrence of new skin cancers over a five-year period of treatment and observation.

Aged↗
PubMed1989

The Skin Cancer Prevention Study: design of a clinical trial of beta-carotene among persons at high risk for nonmelanoma skin cancer.

We describe a randomized clinical trial of oral beta-carotene (50 mg/day) for preventing nonmelanoma skin cancer. It is a multicenter study conducted at sites in California, Minnesota, and New Hampshire. This report describes the design of the study, baseline characteristics of the 1805 randomized patients, changes in their plasma beta-carotene and retinol levels after 1 year of treatment, and plans for statistical analyses. Important features of this study are (1) a high proportion of potential subjects were found to be ineligible or chose not to enter the study, (2) the study agent is readily available over the counter and in common foods, and (3) nonmelanoma skin cancer is a relatively minor health concern for most patients. These considerations necessitated intensive efforts to encourage compliance with the study regimen. There are also some unusual statistical features of the study. One is that the study outcome is routinely assessed only at annual examinations, so the precise time of failure cannot be identified. Also, a secondary goal of the study is to determine whether beta-carotene decreases the average number of new skin cancers per patient per year, and there are no established statistical methods for analysis of data in this situation. Alternative approaches to the analysis are discussed.

Adult↗
PubMed1989

Neuropsychological sequelae of central nervous system prophylaxis in survivors of childhood acute lymphoblastic leukemia.

We assessed neuropsychologically 106 children with acute lymphoblastic leukemia (ALL) who had all received cranial irradiation for the prevention of central nervous system (CNS) leukemia 1-13 years previously. Children were assessed for adverse late effects of their therapy, using age-appropriate Wechsler measures of overall intellectual ability and supplementary tests. Forty-five siblings near in age to the patients were tested as controls. The patients who had had the most intensive central nervous system (CNS) prophylaxis were found to have a WISC-R Full Scale IQ 17 points lower than the sibling control group. Performance IQ was more affected than verbal IQ. The patients were more easily distracted and less able to concentrate. The severity of the aftereffects was related to younger age at the time of CNS prophylaxis and to a higher dose of cranial irradiation but not to time since CNS prophylaxis. CNS prophylaxis using a combination of cranial irradiation and intrathecal methotrexate has lowered the incidence of CNS relapse in childhood ALL but is associated with considerable long-term morbidity in survivors.

Adolescent↗
PubMed1989

Carbohydrate metabolism on high dose growth hormone therapy in children treated for leukaemia.

The effect on carbohydrate metabolism of a high dose growth hormone (GH) regimen (1.2 U/kg per week) was assessed on 24 children who had previously been treated for leukaemia. Sixteen patients received high dose GH and eight patients received a conventional dose of GH (0.6 U/kg per week). Oral glucose tolerance tests (OGTT) were performed at baseline and after 3 months of treatment with GH. For the entire group between 0 and 3 months, there was a significant increase in mean (and standard deviation) fasting plasma glucose (0.3 +/- 0.6 mmol/L), fasting insulin level (11 +/- 26 mU/L), and 2 h insulin level (20 +/- 40 mU/L). One patient, who received a conventional dose of GH, developed substantial carbohydrate intolerance. For the entire group, there was no change in response to a carbohydrate load at 3 months as measured by the area under the plasma glucose or insulin curve. There was no significant difference between conventional and high dose groups at 3 months as assessed by these parameters. This study demonstrates that a higher dose of GH may be used in these children in an attempt to improve their final height, without increased risk of carbohydrate intolerance in the short term.

Blood Glucose↗
PubMed1988

Growth and growth hormone therapy of children treated for leukaemia.

A total of 37 children (24 male, 13 female) who had been treated for leukaemia with chemotherapy and 24 Gy cranial irradiation, and who were disease free for at least 18 months, were commenced on somatrem at a mean of 7.6 years (range, 4.8-12.1 years) after leukaemia diagnosis because of growth rate below the 25th centile for bone age. Peak GH response to provocation (exercise, arginine, insulin hypoglycaemia) was less than 20 milliunits/litre in 27 children (deficient group) and 20 milliunits/litre or more in 10 children (non-deficient group). The mean height SD decrease from diagnosis of leukaemia to commencement of somatrem was 1.98, 86% of the children decreasing by more than 1 SD. Those who were tall for age at leukaemia diagnosis and females were more severely affected. Mean (+/- SD) height velocity increased on somatrem from 2.7 +/- 1.1 to 6.6 +/- 2.2 cm/year during the first 6 months (n = 25), and to 6.0 +/- 1.7 cm/year during the first 12 months (n = 19). No difference in growth response was seen between the sexes or between the deficient and non-deficient groups. Catch-up growth occurred for the first 6 months only. It is concluded that children with a low growth rate after treatment of leukaemia should be considered for GH therapy irrespective of the results of GH provocative tests.

Adolescent↗
PubMed1988

Top secret.

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Career Choice↗
PubMed1987

Growth failure and growth-hormone deficiency after treatment for acute lymphoblastic leukaemia.

In a study of 77 children who had been treated for acute lymphoblastic leukaemia (ALL) with an LSA2L2 (Memorial Sloan-Kettering) chemotherapy protocol plus radiotherapy (24 Gy) as cranial prophylaxis, growth was examined 3.0-9.5 years after diagnosis. The children's growth slowed and they crossed height percentiles towards the end of or after treatment. The Z-score, which reflects the deviation of height measurements from the population mean, was used to assess height change. The mean Z-score was 0.16 at diagnosis, -0.30 2 years later, -0.71 4 years later, and -1.37 6 years later. Height for age had fallen by more than 1 standard deviation of the population mean in 32% of survivors 4 years after diagnosis and in 71% 6 years after diagnosis. Younger children and those tall for age at diagnosis were more severely affected. Growth-hormone (GH) response to standard provocation tests was measured in 46 patients; 30 had partial or complete GH deficiency. Mean pulsatile GH secretion was low in the 34 patients tested. Cranial irradiation is probably the most important causative factor in the development of GH deficiency in survivors of ALL.

Adolescent↗
PubMed1987

Unusual skin rash following withdrawal of oral 6-mercaptopurine in children with leukemia.

Sixteen episodes of a distinctive, papular rash occurred in eight patients following withdrawal of 6-mercaptopurine (6MP) and methotrexate (MTX) used as maintenance therapy for acute lymphoblastic leukemia (ALL). The rash also developed in one of the eight patients when only 6MP was discontinued. The eruption occurred mainly on the face, and in this site resembled the perioral dermatitis seen following withdrawal of topical fluorinated steroids. The rash generally began within 3 weeks of stopping 6MP and lasted 3 to 4 weeks. It failed to improve with the use of topical corticosteroid. We conclude that this rash is caused by the withdrawal of oral 6MP.

Child↗
PubMed1987

Treatment of advanced and inaccessible sarcomas with continuous intra-arterial chemotherapy prior to definitive surgery or radiotherapy--a possible alternative to amputation or disabling radical surgery.

Four patients with advanced and inaccessible soft tissue sarcomas were treated with a regimen of intra-arterial chemotherapy followed by radiotherapy and/or surgical excision. Two of the patients had advanced sarcomas in the buttock and thigh regions which would otherwise have required hindquarter amputation in one case or disarticulation of the hip in the other case. These sarcomas responded significantly to intra-arterial chemotherapy to the extent that subsequent local surgery was effective in eradicating the residual tumours. No viable tumour cells were found in the resected specimens. In both patients amputation was avoided and local tumour eradication was achieved. In the other two patients, advanced and non-resectable sarcomas in the head were first treated with a similar regimen of intra-arterial chemotherapy. In both cases the tumours regressed in size prior to administration of local radiotherapy. After completion of chemotherapy and radiotherapy no viable tumour cells were detected in either lesion. In one case (originally a very extensive sarcoma of the jaw in a 5 year old child) a residual lump was resected but no viable tumour was detected in the resected specimen. These four patients represent our total experience with this plan of management. All responded well and there has been no evidence of local disease recurrence in any of the four patients. One patient (Case 2) did develop pulmonary and bone metastases from which she died 2 years later but the other three patients remain well with no evidence of residual disease, 11 years, 4 years and 20 months after presentation.

Adult↗
PubMed1983

Diagnosis and behavior of juvenile rhabdomyosarcoma.

The main problems in the diagnosis of rhabdomyosarcoma are 1) distinction of undifferentiated examples from other small cell malignancies, especially soft-tissue Ewing's tumor and lymphoma; 2) distinction of spindling examples from fibrosarcoma, leiomyosarcoma, malignant fibrous histiocytoma, polyhistioma, and other sarcomas; 3) recognition of minimal criteria on small samples such as needle biopsy specimens or frozen sections; and 4) recognition of rhabdomyosarcoma in uncommon sites such as bone (mandible), perineum, retroperitoneum, and chest. In 95 pediatric cases diagnosed and treated at Royal Alexandria Hospital for Children--45 after the introduction of combined therapy--minimal diagnostic criteria were assessed. Cross-striations were found in only one third of cases; longitudinal myofibrils were more common and more helpful. There was much overlap between histologic types, and the microscopic patterns had little bearing on prognoses in preadolescent children. Fourteen cases could not be further differentiated ("embryonal sarcoma, probably rhabdomyosarcoma")--nine small-cell tumors; four tumors from genitourinary tract or head for which very small biopsy specimens were available, and one spindling retroperitoneal neoplasm. In all, slight evidence suggested embryonal rhabdomyosarcoma; this evidence included oat-shaped nuclei and, in a few cells, deeply eosinophilic cytoplasm, small elongated processes, or myxoid or alveolar foci--features that exclude lymphoma and Ewing's tumor. In six cases that were originally classified as poorly differentiated or undifferentiated, later material confirmed the presence of rhabdomyosarcoma by showing a predominantly well-differentiated (pleomorphic) or alveolar pattern after therapy. In 14 remaining undifferentiated cases, immunoperoxidase staining with antihuman-myoglobin serum was positive in five. With combined therapy there was 100 per cent survival among patients with paratesticular, limb, and stage I and stage II tumors; considerably improved survival among patients with head and neck, pelvic, and stage III tumors; and 100 per cent mortality among patients with intra-abdominal and stage IV tumors.

Biopsy↗