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PubMedDate not supplied

Carcinoma of the tonsillar region: a comparison of radiation therapy with combined preoperative radiation and surgery.

Ninety-six patients with cancer of the tonsillar region in all stages were studied to compare full-course radiation therapy with surgical salvage to planned radiation and surgery. Full-course radiation therapy was effective in controlling T1 and T2 tumors without neck node involvement. Combined therapy was much more effective in treating T3 tumors with neck node disease. Patients with T4 tumors did poorly regardless of therapy.

Humans↗
PubMed2001

Phase I study of topotecan plus cranial radiation for glioblastoma multiforme: results of Radiation Therapy Oncology Group Trial 9507.

PURPOSE: A phase I trial was conducted by the Radiation Therapy Oncology Group (RTOG) to determine the maximum-tolerated dose of topotecan that could be safely combined with standard cranial radiation for glioblastoma multiforme. A secondary objective was to document the acute and late toxicities of this combination of chemotherapy and radiation. PATIENTS AND METHODS: Forty-seven patients with histologically confirmed glioblastoma multiforme were entered onto this phase I trial. Three cycles of topotecan were administered at 21-day intervals commencing at day 1 of cranial radiotherapy (60 Gy/30 fractions). Each cycle consisted of daily 30-minute intravenous (IV) infusions for 5 days. The dose of topotecan was escalated in three-dose increments from 0.5 mg/m(2)/d to 1.0 mg/m(2)/d to 1.5 mg/m(2)/d in different patient groups. RESULTS: The majority of patients were over age 50. Three dose levels of topotecan were tested. Fifteen patients accrued to level 1 (topotecan dose 0.5 mg/m(2)/d). No grade 4 toxicities were seen. Sixteen patients accrued to level 2 (topotecan dose 1.0 mg/m(2)/d), five of whom had brief episodes of grade 4 neutropenia. Seventeen patients accrued to level 3 (1.5 mg/m(2)/d). Six of these patients had brief episodes of grade 4 neutropenia and four developed grade 3 thrombocytopenia. No serious nonhematologic or late toxicities were seen. Median survival for all patients was 9.7 months. There was no apparent difference in survival by topotecan dose schedule. CONCLUSION: Toxicity was acceptable at an IV topotecan dose of 1.5 mg/m(2)/d administered daily for 5 days every 21 days for three cycles. A phase II trial has been performed using this dose of topotecan.

Adolescent↗
PubMed2000

Conservative surgery and radiation therapy for early stage breast cancer after previous mantle radiation for Hodgkin's disease.

There is an increased incidence of breast cancer in female patients who have previously undergone mantle radiation for Hodgkin's disease. Lumpectomy followed by breast irradiation is generally considered to be contraindicated in such patients owing to the high cumulative radiation dose to the breast. Mastectomy is therefore recommended as the preferred treatment option in these women. We report two cases of breast cancer occurring in women previously treated with mantle radiation for Hodgkin's disease. Both women declined mastectomy and requested breast-conserving treatment.

Adult↗
PubMed1996

Indomethacin attenuation of radiation-induced hyperthermia does not modify radiation-induced motor hypoactivity.

Exposure of rats to 5-10 Gy of ionizing radiation produces hyperthermia and reduces motor activity. Previous studies suggested that radiation-induced hyperthermia results from a relatively direct action on the brain and is mediated by prostaglandins. To test the hypothesis that hypoactivity may be, in part, a thermoregulatory response to this elevation in body temperature, adult male rats were given indomethacin (0.0, 0.5, 1.0, and 3.0 mg/kg, intraperitoneally), a blocker of prostaglandin synthesis, and were either irradiated (LINAC 18.6 MeV (nominal) high-energy electrons, 10 Gy at 10 Gy/min, 2.8 microseconds pulses at 2 Hz) or sham-irradiated. The locomotor activity of all rats was then measured for 30 min in a photocell monitor for distance traveled and number of vertical movements. Rectal temperatures of irradiated rats administered vehicle only were elevated by 0.9 +/- 0.2 degree C at the beginning and the end of the activity session. Although indomethacin, at the two higher doses tested, attenuated the hyperthermia in irradiated rats by 52-75%, it did not attenuate radiation-induced reductions in motor activity. These results indicate that motor hypoactivity after exposure to 10 Gy of high-energy electrons is not due to elevated body temperature or to the increased synthesis of prostaglandins.

Animals↗
PubMed2007

Synchrotron radiation-based irradiance calibration from 200 to 400 nm at the Synchrotron Ultraviolet Radiation Facility III.

A new facility for measuring irradiance in the UV was commissioned recently at the National Institute of Standards and Technology (NIST). The facility uses the calculable radiation from the Synchrotron Ultraviolet Radiation Facility as the primary standard. To measure the irradiance from a source under test, an integrating sphere spectrometer-detector system measures both the source under test and the synchrotron radiation sequentially, and the irradiance from the source under test can be determined. In particular, we discuss the calibration of deuterium lamps using this facility from 200 to 400 nm. This facility improves the current NIST UV irradiance scale to a relative measurement uncertainty of 1.2% (k=2).

Journal Article↗
PubMedDate not supplied

[Radiation and immunity. Interference of ionizing radiation with key immune processes].

Recent evidences of the interference of ionizing radiation into the intimate immune processes are presented in the review. gamma-irradiation induces some events in V-gene rearrangement in T cells. Low-dose irradiation can result in the thymocyte differentiation and activation. Immediately after irradiation stromal thymic cell activity are stimulated and in the later stages it is depressed. Irradiation induces an expression of some functionally important molecules on a surface of the cells of immune system and thus influences the processes of cell interaction, costimulation, adhesion and transvascular migration. It is shown that many events of the signal transduction pathways resulting in radiation-induced and activation-induced apoptosis of lymphocyte are general. This data evidence that the possibility of the choice between the death and activation exists for the cells which are undergone to action of ionizing radiation.

Animals↗
PubMed1978

Proposal for a program in particle-beam radiation therapy in the the United States. A report from the Committee for Radiation Oncology Studies (CROS) and its Particle Subcommittee.

The Program for Particle Therapy proposes utilization of hospital-based particle generators in a nationwide program to evaluate, through meaningful clinical trials, particle radiation therapy and the impact its utilization can have in cancer care. The scientific rationale for use of particle therapy compared to conventional radiation in the effort to achieve uncomplicated local control of cancer, to heal, cure and palliate the patient, indicates the advantages of particle therapy consist of either or both a) enhanced biological effect and b) physical properties leading to improvement in dose distribution. It has been estimated that in tho control local-regional cancer. Any new modality enabling the therapist to increase dose to tumor, while sparing critical normal tissue, can enhance local control and benefit systemic therapy. Limited clinical trials to date warrant further definitive clinical study of particle beams. Physical and biologic considerations of fast-neutron beams have been essentially completed; equipment design, availability, and predicted reliability are good; and the medical community has indicated support of further study. A major clinical investigation can be implemented to provide the scientific basis for judging clinical merit of use of high LET radiations. Concurrently, the first phase of work can be started with protons, negative pions, and heavy ions. It is anticipated that clinical results will accrue much more rapidly with hospital-based units for clinical trials; this Program proposes this transfer of particle technology from the laboratory to such hospital-based facilities in two phases, over a 10-year period.

Clinical Trials as Topic↗
PubMed1990

[Experimental studies on the combined effect of radiation and UFT: 2. fractionated treatments combining UFT and X ray radiation].

The combined effects of fractionated radiation and UFT, which is a mixture of tegafur (FT) and uracil, have been studied using C3H mouse mammary carcinoma. The tumor was implanted in the right hind legs of and irradiated with 300R daily for either 10 or 15 days. UFT (FT 15mg/kg + uracil 33.6mg/kg) was intra-gastrically administered 2 hr. before irradiation. Dose modifying factor (DMF) of UFT obtained from the tumor growth delay assay was 1.52 for 10 fractions (3,000R) and 1.27 for 15 fractions (4,500R). The continuous administrations of UFT for one month after combination treatment suppressed the tumor regrowth. It is suggested that UFT is a useful radiosensitizer for concurrent fractionated radiation and useful adjuvant agent after radiation therapy.

Animals↗
PubMed1990

[The use of radiodiagnostic apparatus as human radiation counters in large-scale radiation accidents].

The problem of dosimetry of internal irradiation necessitates the use of human radiation counters (HRC). A state system of radiation safety should be based on a HRC stock in case of large-scale radiation accidents. Radiodiagnostic units can run in the HRC mode therefore they must be considered as an active reserve widely spread throughout the country. Radiodiagnostic devices can be used for control of the thyroid level of 131I and the whole-body content of a mixture of 134Cs and 137Cs.

Accidents↗
PubMed1986

Cisplatin and etoposide before definitive radiation therapy for inoperable squamous carcinoma, adenocarcinoma, and large cell carcinoma of the lung: a phase I-II study of the Radiation Therapy Oncology Group.

A trial of "neoadjuvant" cisplatin-etoposide and radiation therapy was conducted by the Radiation Therapy Oncology Group for non-small cell carcinoma of the lung limited to the thorax. Thirty evaluable patients were studied: two achieved complete response and four achieved partial response after chemotherapy. All patients underwent radiation therapy as planned, with no unusual acute reactions. Sixteen patients had local failure, and 13 had distant metastasis. Twenty-seven patients are dead, two are alive with cancer, and one is clinically free of cancer at 145 weeks. Five of six patients who survived greater than or equal to 2 years after treatment had adenocarcinomas. There was no unexpected late toxicity. This combination of chemotherapy and radiotherapy is unlikely to improve results in the treatment of inoperable non-small cell carcinoma of the lung over those with radiotherapy alone.

Actuarial Analysis↗
PubMed1988

[Results of radiation therapy of stage I-II non-Hodgkin's lymphoma localized in the head and neck--a report of the Japanese Lymphoma Radiation Therapy Study Group].

A retrospective analysis of 1514 patients with non-Hodgkin's lymphoma treated between 1972 and 1985 was performed. Of these cases, 114 with histology of low-grade malignancy and 750 with intermediate malignancy were localized in the head and neck. All patients received definitive course of radiation therapy, including 390 cases with adjuvant chemotherapy. For cases with low-grade malignancy, all cases were locally controlled and five-year relapse free survival rates were 85% in stage I, and 75% in stage II. For cases with intermediate malignancy, local control rates were 97% in stage I, and 87% in stage II. Five-year survival rates were 67% in stage I and 50% in stage II. There were no benefit on survival rates from adjuvant use of chemotherapy with radiation therapy as compared to radiation therapy alone.

Head and Neck Neoplasms↗
PubMed1988

[Results of radiation therapy of stage II non-Hodgkin's lymphoma of the Waldeyer's ring: a report of the Japanese Lymphoma Radiation Therapy Study Group].

A retrospective analysis of 245 patients with stage II non-Hodgkin's lymphoma of the Waldeyer's ring treated between 1972 and 1985 was performed. Treatment consisted of radiation therapy alone in 96 patients and 149 patients were treated with chemotherapy combined. Five-year survival and relapse-free survival rates were 57% and 50%, respectively. For cases with DH, they were 64% and 55% respectively, and for DLPD 31% and 27%, respectively. Of the cases with relapse, 21% were seen in stomach or intestine. There were no difference on survival rates between radiation therapy alone and chemotherapy combined with radiation therapy.

Combined Modality Therapy↗
PubMed1982

Immunosuppressive effects of ultraviolet (280-320 nm) radiation and psoralen plus ultraviolet (320-400 nm) radiation in mice.

Contact hypersensitivity (CHS), a cell-mediated immunologic reaction, can be induced in mice by application of a contact-sensitizing chemical to the shaved skin. Exposing the animals to UV radiation from FS40 sunlamps inhibits this immune response. This inhibition is systemic, since the sensitizer need not be applied to the irradiated site of the animal. The mechanism whereby UV radiation prevents CHS appears to involve the production of suppressor T-lymphocytes. Recent evidence suggests that UV exposure of mice alters the way in which certain antigens are processed, and this altered processing or presentation of antigen results in the activation of the suppressor cell pathway, rather than leading to immunization. Treatment of mice with a photosensitizer, psoralen, plus UV (320-400 nm) radiation also suppresses CHS systemically, but whether the cellular mechanisms are the same as those underlying the suppression from the shorter UV wavelengths remains to be determined. The possible role of these immunosuppressive events in photocarcinogenesis is discussed.

Animals↗
PubMed1983

Radiation inactivation of (Na,K)-ATPase, an enzyme showing multiple radiation-sensitive domains.

The radiation inactivation of membrane-bound (Na,K)-ATPase from pig kidney was studied by irradiating lyophilized enzyme preparations in vacuo. Various results were obtained depending upon the function assayed. The apparent target size of (Na,K)-ATPase activity was found to be 264 kDa an the high affinity binding sites for ATP, vanadate, and ouabain (bound in the presence of Na+, Mg2+, and ATP) had an apparent target size of 145 kDa. The binding of ouabain in the presence of Mg2+ alone seemed to depend upon the integrity of a domain with a target size of approximately 100 kDa. Na-ATPase and p-nitrophenyl phosphatase, assayed under a variety of conditions, gave inactivation kinetics that did not conform to classical target theory. All the results have been assembled into a model according to which 1) the membrane-bound enzyme is an (alpha beta)2-dimer; 2) there is radiation energy coupling between all four peptides in a molecule, and 3) each alpha-peptide consists of five discrete and independent radiation-sensitive domains with specific functions in the enzymatic reactions catalyzed by the sodium pump.

Adenosine Triphosphate↗
PubMed1984

Molecular signals in antigen presentation. II. Activation of cytolytic cells in vitro after ultraviolet radiation or combined gamma and ultraviolet radiation treatment of antigen-presenting cells.

Murine low-density spleen cells have potent antigen-presenting ability in a hapten-specific cytolytic T lymphocyte (CTL) system using the hapten azobenzenearsonate (ABA). Exposure of these cells to 0.33 KJ/m2 of ultraviolet radiation (UVR) after coupling to hapten results in markedly inhibited antigen-presenting function that can be substantially corrected or bypassed by interleukin 1 (IL 1). These results have been interpreted to reflect an inhibition of Lyt-1+ T cell activation by UVR-treated APC. Treatment of these cells sequentially with 1500 rad of gamma-radiation (GR) prior to hapten coupling, followed by 0.33 KJ/m2 of UVR radiation after coupling, results in an antigen-presenting defect only minimally improved by IL 1. However, partially purified interleukin 2 (IL 2) can completely bypass or correct this defect. Thus, combined GR and UVR induces a different or more profound defect in APC function when compared to UVR alone. However, these cells do provide a signal(s) other than hapten necessary for CTL activation because ABA-coupled high density spleen cells do not activate CTL cells, even with the addition of IL 2. Fluorescence-activated cell sorter analysis demonstrates that exposure of these low density spleen cells to GR or UVR results in decreased I-A antigen expression at 24 hr than either alone. The addition of nonhapten-coupled low-density APC partially reconstitutes the ability of combined GR/UVR-treated LD-APC to present antigen, and this effect is enhanced by the administration of exogenous IL 1. This occurs despite a lack of significant accessory cell activity by the LD-APC for the ABA hapten, and indicates that combined GR/UVR-treatment of APC is not functionally equivalent to completely removing them.

Animals↗
PubMed1982

The influence of infrared radiation on short-term ultraviolet-radiation-induced injuries.

Because heat has been reported to influence adversely short- and long-term ultraviolet (UV)-radiation-induced skin damage in animals, we investigated the short-term effects of infrared radiation on sunburn and on phototoxic reactions to topical methoxsalen and anthracene in human volunteers. Prior heating of the skin caused suppression of the phototoxic response to methoxsalen as evidenced by an increase in the threshold erythema dose. Heat administered either before or after exposure to UV radiation had no detectable influence on sunburn erythema or on phototoxic reactions provoked by anthracene.

Adult↗