Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0025202 (melanoma)
 69,561 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hyperthermia has been combined with conventional radiation methods to achieve enhanced tumor destruction. We combined iodine 125 seeds with ferromagnetic thermoseeds in a single plaque to simultaneously deliver radiation and heat in a rabbit model of choroidal melanoma. Initially, six ferromagnetic thermoseeds were placed in parallel on a 14-mm episcleral plaque. The plaques were placed on normal rabbit eyes and on eyes containing transvitreally implanted choroidal melanoma. The heating response was assessed in both normal and tumor-containing eyes. Rigid copper-constantan and flexible Baily thermocouples were used to monitor temperature responses. The animals were subjected to an electromagnetic field of 100 kHz, with power of 1100 to 1500 W. The thermoseeds autoregulated at 48.2 degrees C. Scleral temperatures stabilized at 45.8 degrees C +/- 0.4 degrees C (SD), while temperatures at the base of the tumor stabilized at 43.6 degrees C +/- 0.1 degrees C. Ferromagnetic thermoseeds were then combined with iodine 125 seeds. Similar temperature responses were recorded, and autoradiographic findings confirmed a uniform radiation distribution. Varying the amount or type of ferromagnetic material in the thermoseeds allows the delivery of heat at virtually any temperature. Ferromagnetic hyperthermia may provide a more simplified approach over currently available methods of heat delivery.
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PMID:Ferromagnetic hyperthermia and iodine 125 brachytherapy in the treatment of choroidal melanoma in a rabbit model. 280 4

The influence of cimetidine on antiviral activity of leukocyte interferon (IFN-alpha (Le] was studied in plaque-reduction assays using Utrecht (U) amnion cells challenged with vesicular stomatitis virus (VSV) and in CPE inhibition assays using A549 cells challenged with encephalomyocarditis (EMC) virus and WISH cells challenged with VSV. The IFN-alpha (Le)-induced antiviral activity was slightly enhanced in cells treated with cimetidine, whereas cimetidine treatment alone did not show any antiviral effect. The observed titer (OT) was significantly higher (p less than 0.05) in cells treated with cimetidine together with IFN-alpha (Le) compared with the control without cimetidine. The effect of cimetidine on IFN-alpha (Le)-induced cell growth inhibition was studied on Daudi (a Burkitt's lymphoma cell line) and on G361 (a melanoma cell line) cells. The growth of these cells was slightly suppressed by cimetidine alone. When cells were treated with IFN-alpha (Le)/cimetidine, the cell growth inhibition rates were significantly higher (p less than 0.02) than the rates obtained with IFN-alpha (Le) or cimetidine alone. These results indicate that cimetidine can enhance the antiviral as well as the antiproliferative activities of IFN-alpha (Le) in "in vitro" studies.
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PMID:Antiviral and antiproliferative activities of human leukocyte interferon potentiated by cimetidine in vitro. 299 35

Visualization of the position of an episcleral plaque in relation to the underlying choroidal melanoma during the early radiation treatment period reconfirms accurate plaque location and may help assure optimal treatment. We used high-resolution B-scan echography to confirm the position of the episcleral plaque in 16 consecutive cases of choroidal melanoma. The technique is most useful for well-defined tumors as small as 3 mm in height whose anterior border does not extend beyond the ora serrata.
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PMID:Echographic verification of radioactive plaque position in the treatment of melanomas. 305 56

We have previously demonstrated that the polycyclic aromatic hydrocarbons benzo[a]pyrene (B[a]P) and 7,12-dimethylbenz[a]anthracene (DMBA) produce a marked decrease in spleen weight, spleen and bone marrow cellularity and the number of IgM plaque forming cells generated in response to a T-dependent antigen. Exposure to DMBA, but not B[a]P, increased susceptibility to challenge with PYB6 tumor cells and Listeria monocytogenes suggesting that DMBA produces immune impairment involving cell-mediated immunity (CMI) and tumor resistance mechanisms. In this study, female B6C3F1 mice received total doses of 5, 50 and 100 micrograms DMBA/g of body weight in ten subcutaneous injections of 0.5, 5, or 10 micrograms/g over a 2 week period and CMI and tumoricidal functions were examined 3-5 days following the final injection of DMBA. DMBA exposed mice exhibited suppressed splenic cellularity (decreased 62%) and decreased numbers of resident peritoneal cells (down to 47% of control), although the proportion of T cell and T cell subsets, B cells and macrophages in spleens from exposed mice was not altered. Lymphocyte blastogenesis in response to mitogens was suppressed up to 49% with PHA, 48% with Con A and 76% with LPS. The response to alloantigens in unidirectional mixed lymphocyte culture was depressed as much as 73% following exposure to DMBA. Tumor cytolysis mediated by cytotoxic T cells (CTL) was impaired at doses of 50 and 100 micrograms DMBA/g body weight (88-95% suppressed respectively) as was natural killer cell (NK)-mediated tumor cytolysis (24% and 55% suppressed). Antibody-dependent cytotoxicity was significantly depressed in the highest exposure group. Peritoneal macrophage accumulation was decreased in DMBA-treated mice, but the macrophages present were pushed towards activation. The ability of DMBA-exposed mice to eliminate intravenously injected B16F10 tumor cells from the lungs was not impaired. Since NK- and M phi-mediated tumor cytotoxicity are thought to be primarily responsible for pulmonary elimination of B16F10 melanoma cells, the extent of NK suppression observed following DMBA exposure appeared to be insufficient to alter in vivo B16F10 pulmonary elimination. In contrast, the loss of the CTL tumoricidal response correlated with an increased frequency of tumors following challenge with PYB6 tumor cells.
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PMID:Immunosuppression following 7,12-dimethylbenz[a]anthracene exposure in B6C3F1 mice--II. Altered cell-mediated immunity and tumor resistance. 308 44

The Collaborative Ocular Melanoma Study (COMS) is an international, multicenter-controlled study. The organization includes an Executive Committee, Steering Committee, 6 Central Units, 32 Clinical Centers, and a Data and Safety Monitoring Committee. Scientifically, the COMS consists of (1) a randomized trial of patients with medium choroidal melanoma treated with enucleation versus iodine-125 plaque irradiation, (2) a randomized trial of patients with large choroidal melanoma treated with enucleation versus preenucleation external beam irradiation and enucleation, and (3) a prospective observational study of patients with small choroidal melanoma to determine whether a randomized trial of treatment is appropriate. In design and conduct of the COMS, special consideration is given to biostatistics and sample size considerations, iodine-125 plaque irradiation of choroidal melanoma, and coordinated ocular melanoma research. Recruitment is in progress. However, the pool of eligible patients is limited and the COMS needs the continued support and cooperation of ophthalmologists throughout the United States and Canada.
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PMID:Enucleation versus plaque irradiation for choroidal melanoma. 317 30

The first two Swedish cases of primary bilateral malignant melanoma of the choroid are presented. In one case bilateral histological confirmation was obtained as both eyes were enucleated. In the other case one eye was enucleated and the other irradiated with an episcleral ruthenium plaque. Sweden has a population of 8.38 millions, so that bilateral choroidal melanomas may be less rare than previously thought.
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PMID:Two cases of primary bilateral malignant melanoma of the choroid. 337 18

A calculation is described that enables the rapid assessment of dose rate at various points of interest within the eye (lens, optic nerve, etc.) for the treatment of choroidal melanoma by plaque therapy. 125I seeds are used as the radiation source. The location of the plaque and its associated seeds relative to the eye (in a Cartesian coordinate system) is determined from the description of the tumor, as drawn and dimensioned on a fundus-view diagram by the ophthalmologist. This requires a computer to numerically solve an equation, which is derived in the framework of spherical geometry. Further results of this calculation yield data files that serve as the input to a conventional brachytherapy treatment planning program. This enables the visualization of the dose distribution within a plane that contains the major axis of the tumor in order to assess the adequacy of the treated volume.
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PMID:The generalized geometry of eye plaque therapy. 340 40

Two hundred and twenty-three patients treated by cobalt plaque for uveal melanoma were compared with 416 patients treated by enucleation for uveal melanoma in terms of patient survival. The median follow-up time for the patients treated by cobalt plaque was 4.3 years. Kaplan-Meier survival curves were calculated up to five years following treatment based on time to tumour-related deaths. Cox's proportional hazards multivariate analysis was performed to determine which variables were related to melanoma-related deaths while controlling for age, size, and location of the tumours. Statistically significant predictive factors were location of tumour and largest tumour dimension. There was not a statistically significant difference in survival between patients treated by cobalt plaque and those treated by enucleation.
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PMID:Cobalt plaque versus enucleation for uveal melanoma: comparison of survival rates. 341 41

An iodine-125 eye plaque was used to treat 58 patients with choroidal melanoma. Patients were followed up for a mean of 48.7 months. Fifty patients had medium-sized lesions (height between 3.1 and 8.0 mm and base diameter less than 16.0 mm), and six patients had large lesions. There were 24 lesions less than 3.0 mm from the optic nerve. The average radiation dose to the apex of the tumor was 8,468 cGy (dose rate, 71 cGy per hour). Initial local disease control was achieved in 50 patients (86.2%). One patient with local treatment failure received another plaque treatment, which controlled disease, so the total disease control rate was 87.9%. Only eight patients died of their disease. Complications were similar to those with other treatment methods, but none of the patients in this study developed optic nerve atrophy.
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PMID:Choroidal melanoma: I-125 plaque therapy. 342 Feb 67

Clinical risk factors were assessed prospectively in a nonrandomized concurrent observational study of 237 patients with posterior uveal malignant melanoma. One hundred forty of these patients were treated with enucleation, and 97 underwent cobalt plaque radiotherapy. Tumor size and location of the anterior tumor margin proved to be the most significant clinical risk factors for death from metastatic melanoma. When Cox proportional hazards modeling was used to adjust for recognized intergroup differences in risk factors, the effect of therapy (enucleation vs cobalt plaque radiotherapy) on survival time was not statistically significant. We discuss the implications of this study for a randomized clinical trial of enucleation vs cobalt plaque therapy or comparable forms of irradiation.
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PMID:Enucleation vs cobalt plaque radiotherapy for malignant melanomas of the choroid and ciliary body. 351 77


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