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Radiation Alone (radiation + alone)

Distribution by Scientific Domains

Medical Sciences	66%
Life Sciences	33%

Selected Abstracts

Swallowing disorders in the first year after radiation and chemoradiation

HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 2 2008
Jeri A. Logemann PhD
Abstract Background Radiation alone or concurrent chemoradiation can result in severe swallowing disorders. This manuscript defines the swallowing disorders occurring at pretreatment and 3 and 12 months after completion of radiation or chemoradiation. Methods Forty-eight patients (10 women and 38 men) participated in this study involving videofluorographic evaluation of oropharyngeal swallow at the 3 time points. Results At baseline, patients had some swallow disorders, probably related to presence of their tumor. At 3 months posttreatment, frequency of reduced tongue base retraction, slow or delayed laryngeal vestibule closure, and reduced laryngeal elevation increased from baseline. Some disorders continued at 12 months posttreatment. Functional swallow decreased over time in patients treated with chemoradiation, but not those treated with radiation alone. Discussion Chemoradiation results in fewer functional swallowers than radiation alone at 12 months posttreatment completion. © 2007 Wiley Periodicals, Inc. Head Neck, 2008 [source]

UV-B effect on Quercus robur leaf litter decomposition persists over four years

GLOBAL CHANGE BIOLOGY, Issue 4 2001
K. K. Newsham
Summary The effects of elevated UV-B (280,315 nm) radiation on the long-term decomposition of Quercus robur leaf litter were assessed at an outdoor facility in the UK by exposing saplings to elevated UV-B radiation (corresponding to a 30% increase above the ambient level of erythemally weighted UV-B, equivalent to that resulting from a c. 18% reduction in ozone column) under arrays of cellulose diacetate-filtered fluorescent UV-B lamps that also produced UV-A radiation (315,400 nm). Saplings were also exposed to elevated UV-A radiation alone under arrays of polyester-filtered fluorescent lamps and to ambient solar radiation under arrays of nonenergized lamps. After 8 months of irradiation, abscised leaves were placed into litter bags and allowed to decompose in the litter layer of a mixed deciduous woodland for 4.08 years. The dry weight loss of leaf litter from saplings irradiated with elevated UV-B and UV-A radiation during growth was 17% greater than that of leaf litter irradiated with elevated UV-A radiation alone. Annual fractional weight loss of litter (k), and the estimated time taken for 95% of material to decay (3/k) were respectively increased and decreased by 27% for leaf litter exposed during growth to elevated UV-B and UV-A radiation, relative to that exposed to UV-A alone. The present data corroborate those from a previous study indicating that UV-B radiation applied during growth accelerates the subsequent decomposition of Q. robur leaf litter in soil, but indicate that this effect persists for over four years after abscission. [source]

Swallowing disorders in the first year after radiation and chemoradiation

Definitive radiotherapy with interstitial implant boost for squamous cell carcinoma of the tongue base

HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 5 2005
Omur Karakoyun-Celik MD
Abstract Background. The purpose of this study was to examine the long-term outcome of a cohort of patients with unresected base of tongue carcinoma who received interstitial brachytherapy after comprehensive external beam radiation therapy. Methods. Between 1983 and 2000, 122 patients with primary or recurrent squamous cell carcinoma of the oropharynx or oral cavity received interstitial brachytherapy as part of their overall management. Forty patients had primary, unresected carcinoma of the base of tongue and are the subjects of this analysis. The median age was 54 years. Fifty-four percent had T3 or T4 disease, and 70% had clinical or radiographic lymphadenopathy. Twenty-four (60%) received two to three cycles of neoadjuvant chemotherapy. The oropharynx, bilateral neck, and supraclavicular fossae were comprehensively irradiated, and the tongue base received a median external beam dose of 61.2 Gy (50,72 Gy). The primary site was then boosted with an interstitial 192Iridium implant by use of a gold-button single-strand technique and three-dimensional treatment planning. The dose rate was prescribed at 0.4 to 0.5 Gy/hr. The median implant dose was 17.4 Gy (9.6,24 Gy) and adjusted to reach a total dose to the primary tumor of 80 Gy. N2 to 3 disease was managed by a planned neck dissection performed at the time of the implant. Results. The median follow-up for all patients was 56 months, and the overall survival rates were 62% at 5 years and 27% at 10 years. The actuarial primary site control was 78% at 5 years and 70% at 10 years. The overall survival and primary site control were independent of T classification, N status, or overall stage. Systemic therapy was associated with an improvement in overall survival (p = .04) and a trend toward increased primary site control with greater clinical response. There were seven documented late effects, the most frequent being grade 3 osteonecrosis (n = 2), grade 2 swallowing dysfunction (n = 2), trismus (n = 2), and chronic throat pain (n = 1). Conclusions. In an era of greatly improved dose distributions made possible by three-dimensional treatment planning and intensity-modulated radiation therapy, brachytherapy allows a highly conformal dose to be delivered in sites such as the oropharynx. If done properly, the procedure is safe and delivers a dose that is higher than what can be achieved by external beam radiation alone with the expected biologic advantages. The long-term data presented here support an approach of treating advanced tongue base lesions that includes interstitial brachytherapy as part of the overall management plan. This approach has led to a 78% rate of organ preservation at 5 years, with a 5% incidence of significant late morbidity (osteonecrosis) that has required medical management. © 2005 Wiley Periodicals, Inc. Head Neck27: XXX,XXX, 2005 [source]

Preoperative chemoradiation versus radiation alone for stage II and III resectable rectal cancer: A systematic review and meta-analysis

INTERNATIONAL JOURNAL OF CANCER, Issue 12 2009
Wim Ceelen
Abstract Combining chemotherapy with preoperative radiotherapy (RT) has a sound radiobiological rationale. We performed a systematic review and meta-analysis of trials comparing preoperative RT with preoperative chemoradiation (CRT) in rectal cancer patients. The Cochrane Central Register of Controlled Trials, Web of Science, Embase and Medline (Pubmed) were searched from 1975 until June 2007. Dichotomous parameters were summarized using the odds ratio while time to event data were analyzed using the pooled hazard ratio for death. From the primary search result of 324 trials, 4 relevant randomized trials were identified. The addition of chemotherapy significantly increased grade III and IV acute toxicity (p = 0.002) while no differences were observed in postoperative morbidity or mortality. Preoperative CRT significantly increased the rate of pathological complete response (p < 0.001) although this did not translate into a higher sphincter preservation rate (p = 0.29). The local recurrence rate was significantly lower in the CRT group (p < 0.001). No statistically significant differences were observed in disease free survival (p = 0.89) or overall survival (p = 0.79). Compared to preoperative RT alone, preoperative CRT improves local control in rectal cancer but is associated with a more pronounced treatment related toxicity. The addition of chemotherapy does not benefit sphincter preservation rate or long-term survival. Future trials should address improvements in the rate of distant metastasis and overall survival by incorporating more active chemotherapy. © 2008 UICC [source]

Inactivation of Mycobacterium avium ssp. paratuberculosis in milk by UV treatment

LETTERS IN APPLIED MICROBIOLOGY, Issue 2 2009
J. Donaghy
Abstract Aims:, To determine the effect of UV radiation on the viability of two strains of Mycobacterium avium ssp. paratuberculosis (Map) inoculated into milk. Methods and Results:,Mycobacterium avium ssp. paratuberculosis in a ultra heat treated milk matrix was subjected to increasing doses of UV-C radiation from 0 to 1836 mJ ml,1 using a pilot-scale UV reactor (20 l capacity). Survival of Map was monitored by culture on Herrold's egg yolk medium, Middlebrook 7H10 medium and the FASTPlaqueTBÔ phage assay. Differences in sensitivity to UV treatment were observed between strains, however, at 1000 mJ ml,1 a Map kill rate of 0·1,0·6 log10 was achieved regardless of strain used or method employed to enumerate Map. Although the inactivation trend was similar on the culture and phage assay, the former gave a consistently higher viable count. Conclusions:, The use of UV radiation alone does not represent an alternative to current pasteurization regimes for a large reduction in viable Map in milk. Significance and Impact of the Study:, To the authors' knowledge the work here represents the first pilot-scale UV treatment process used to assess UV efficacy to inactivate Map in milk. The results are similar to those obtained with a laboratory-scale process indicating the difficulties associated with UV treatment of an opaque liquid and the recalcitrance of Map towards inimical treatments. [source]

Selective neck dissection and deintensified postoperative radiation and chemotherapy for oropharyngeal cancer: A subset analysis of the university of pennsylvania transoral robotic surgery trial,

THE LARYNGOSCOPE, Issue 9 2010
Gregory S. Weinstein MD
Abstract Objectives/Hypothesis: The purpose of this study was to determine the regional recurrence rate of node-positive oropharyngeal squamous cell carcinoma (OPSCC) in patients undergoing transoral robotic surgery (TORS) and selective neck dissection (SND) followed by observation, radiation, or concurrent chemoradiation. Study Design: A prospective, phase I, single-arm study was conducted. All OPSCC patients who voluntarily participated in a surgical trial with TORS and SND at an academic tertiary referral center from May 2005 to July 2007 were included. Methods: Thirty-one patients with previously untreated OPSCC undergoing TORS and SND (29 unilateral and two bilateral) were included. There were 29 males and two females, with ages ranging from 36 to 76 years (median = 55 years) with one palate, one lateral wall, 17 tonsil, 11 base of tongue, and one vallecula primary tumor classified as follows: T1 (n = 9, 29%), T2 (n = 15, 48.4%), T3 (n = 7, 22.6%), N0 (n = 6, 19.4%), N1 (n = 15, 48.4%), N2b (n = 10, 32.3%), and N2c (n = 1, 3.2%). There were three stage I (9.7%), two stage II (6.5%), 15 stage III (48.4%) and 11 stage IVa (35.5%) patients. Twenty-two patients were treated postoperatively with adjuvant therapy (12 radiation alone and 12 combined radiation and chemotherapy). Primary outcome measured was regional recurrence rate. Results: There was one regional recurrence on the contralateral, non-operated neck and one distant recurrence among the 31 patients who underwent SND. Conclusions: SND after TORS resection of primary OPSCC enables the use of selective and deintensified adjuvant therapy to reduce regional recurrence rates. Laryngoscope, 2010 [source]

The Effect of treatment on survival in patients with advanced laryngeal carcinoma,

THE LARYNGOSCOPE, Issue 7 2009
Christine G. Gourin MD
Abstract Objectives/Hypothesis: Over the last 2 decades, survival from laryngeal cancer has decreased. We sought to identify factors associated with decreased survival in laryngeal cancer. Methods: Patients diagnosed with laryngeal squamous cell carcinoma from 1985 to 2002 were retrospectively reviewed. Results: A total of 451 patients met study criteria. Five-year survival rates were 85% for stage I, 77% for stage II, 51% for stage III, and 35% for stage IV disease. Survival for patients with stage I,III disease was similar for patients treated operatively or nonoperatively (P = .4). However, patients with stage III disease treated nonoperatively had worse survival with radiation alone (XRT) compared to chemoradiation (CR) (P = .006). Patients with stage IV disease had significantly better survival with surgery (49%) than CR (21%) or XRT alone (14%) (P < .0001). Analysis by primary tumor stage demonstrated that survival for T1,T3 disease was independent of treatment modality (P = .2); however, for T4 patients, operative treatment was associated with significantly better survival (55%) than CR (25%) or XRT (0%) (P < .0001). Proportional hazards models confirmed significantly worse survival for stage IV, T4, N2 or N3 disease, and nonoperative treatment. For T4 disease, after controlling for nodal status, nonoperative treatment was the only significant predictor of worse survival. Conclusions: Primary surgical treatment is associated with improved survival for patients with stage IV disease and specifically T4 primary tumors. These data suggest that the observed national decrease in survival from laryngeal cancer may be due to a shift toward nonoperative treatment in that subset of patients with advanced primary disease. Laryngoscope, 2009 [source]

Sensitivity of human glioma U-373MG cells to radiation and the protein kinase C inhibitor, calphostin C

CELL PROLIFERATION, Issue 1 2001
M. Acevedo-Duncan
We assessed the radiosensitivity of the grade III human glioma cell line U-373MG by investigating the effects of radiation and the specific protein kinase C inhibitor, calphostin C on the cell cycle and cell proliferation. Irradiated glioma U-373MG cells progressed through G1 -S and underwent an arrest in G2 -M phase. The radiosensitivity of U-373MG cells to graded doses of either photons or electrons was determine by microculture tetrazolium assay. The data was fitted to the linear-quadratic model. The proliferation curves demonstrated that U-373MG cells appear to be highly radiation resistant since 8 Gy was required to achieve 50% cell mortality. Compared to radiation alone, exposure to calphostin C (250 n m) 1 h prior to radiation decreased the proliferation of U-373MG by 76% and calphostin C provoked a weakly synergistic effect in concert with radiation. Depending on the time of application following radiation, calphostin C produced an additive or less than additive effect on cell proliferation. We postulate that the enhanced radiosensitivity observed when cells are exposed to calphostin C prior to radiation may be due to direct or indirect inhibition of protein kinase C isozymes required for cell cycle progression. [source]