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Concomitant boost radiation plus concurrent cisplatin for advanced head and neck carcinomas: radiation therapy oncology group phase II trial 99-14.

PURPOSE: To investigate the feasibility of combining concomitant boost accelerated radiation regimen (AFX-C) with cisplatin and to assess its toxicity and the relapse pattern and survival in patients with advanced head and neck carcinoma (HNC). PATIENTS AND METHODS: Between April and November of 2000, 84 patients with stage III to IV HNC who met the eligibility criteria were enrolled; 76 of these patients were analyzable. Radiation consisted of 72 Gy in 42 fractions over 6 weeks (daily for 3.5 weeks, then twice a day for 2.5 weeks). Cisplatin dose was 100 mg/m(2) on days 1 and 22. Tumor and clinical status were assessed, and acute late toxicities were graded. RESULTS: Sixty-five patients (86%) received both radiation and chemotherapy per protocol or with minor variations. The estimated 2-year locoregional relapse and distant metastasis rates were 34.7% and 16.1%, respectively. The estimated 2-year overall survival and disease-free survival rates were 71.6% and 53.5%, respectively. Three patients (4%) died of complications, 19 patients (25%) had acute grade 4 toxicity, and 49 patients (64%) had acute grade 3 toxicity. The 2-year cumulative incidence of late grade 3 to 5 toxicities was 51.3%. CONCLUSION: These data showed that it was feasible to combine AFX-C with cisplatin. The compliance to therapy was high, and the locoregional control and survival rates achieved compared favorably with AFX-C alone or other concurrent chemoradiation regimens tested by the Radiation Therapy Oncology Group. A phase III trial comparing AFX-C plus cisplatin against standard radiation plus cisplatin is ongoing to determine whether the use of AFX-C in the concurrent chemoradiation setting further improves outcome.

Adult↗

Single brain metastases: surgery plus radiation or radiation alone.

We reviewed the records of patients treated for single brain metastases from non-small-cell lung cancer for 1978 through 1982. Forty-three patients received surgical treatment, including 37 who had surgery plus postoperative whole-brain radiation therapy and 6 patients who had surgery after failing to respond to radiation therapy. The surgically treated patients were matched with 43 patients treated with radiation therapy alone. The combined therapy group had significantly longer survivals than those treated with radiation therapy alone (19 months versus 9 months). The rates of local recurrence and neurologically related deaths were significantly higher in the radiation therapy-alone group. Patients treated with combined therapy survived longer, and the increased survival was due to lower recurrence of brain metastases after surgery and fewer neurologically related deaths.

Adenocarcinoma↗

Is interferon-alpha and retinoic acid combination along with radiation superior to chemo-radiation in the treatment of advanced carcinoma of cervix?

Locally advanced cervical cancers comprise a large majority of the gynecologic cancers in India and other developing countries. Concurrent chemo-radiation has improved the survival of high risk stage I and stage II cervical cancers. There is no evidence that the same survival benefit has been achieved with chemo-radiation in stage III and stage IV disease. Interferon-alpha and Retinoic acid have synergistic anti-proliferative activity. In combination with radiation, they substantially enhance the sensitivity of the squamous carcinoma cells to radiation. Based on these observations from the in vitro studies, a few clinical trials have evaluated the combination of interferon-alpha and Retinoic acid, concomitant with radiation, to treat cervical cancers. The results from these early trials were encouraging and the combination had minimal toxicities. However, till date, no phase III randomized controlled trial has been done to evaluate this therapeutic modality.

Antineoplastic Combined Chemotherapy Protocols↗

A phase I/II study of external beam radiation, brachytherapy, and concurrent chemotherapy for patients with localized carcinoma of the esophagus (Radiation Therapy Oncology Group Study 9207): final report.

BACKGROUND: A multiinstitutional, prospective study of the Radiation Therapy Oncology Group (RTOG) was designed to determine the feasibility and toxicity of chemotherapy, external beam radiation, and esophageal brachytherapy (EB) in a potentially curable group of patients with adenocarcinoma or squamous cell carcinoma of the esophagus. A preliminary analysis indicated a 17% 1-year actuarial risk of treatment-related fistulas. A final analysis of this study was considered important to determine the median survival time, local control, and late toxicity associated with this treatment regimen. METHODS: Planned treatment was 50 grays (Gy) of external beam radiation (25 fractions given over 5 weeks) followed 2 weeks later by EB (either high-dose-rate 5 Gy during Weeks 8, 9, and 10, for a total of 15 Gy, or low-dose-rate 20 Gy during Week 8). Chemotherapy was given during Weeks 1, 5, 8, and 11, with cisplatin 75 mg/m(2) and 5-fluorouracil 1000 mg/m(2)/24 hours in a 96-hour infusion. RESULTS: Of the 49 eligible patients, 45 (92%) had squamous histology and 4 (6%) had adenocarcinoma. Forty-seven patients (96%) completed external beam radiation plus at least 2 courses of chemotherapy, whereas 34 patients (69%) were able to complete external beam radiation, EB, and at least 2 courses of chemotherapy. The estimated survival rate at 12 months was 49%, with an estimated median survival of 11 months. Life-threatening toxicity or treatment-related death occurred in 12 (24%) and 5 (10%) cases, respectively. Treatment-related esophageal fistulas occurred in 6 cases (12% overall, 14% of patients starting EB) at 0.5-6.2 months from the first day of brachytherapy, leading to death in 3 cases. CONCLUSIONS: In this study, severe toxicity, including treatment-related fistulas, occurred within 7 months of brachytherapy. Based on the 12% incidence of fistulas, the authors continue to urge caution in employing EB, particularly when used in conjunction with chemotherapy.

Adenocarcinoma↗

[The perception of the radiation situation and assessment of their own health status by the population living in an area under strict radiation control].

Studies of subjective perception of the radiation situation, self-estimation of the health status by the population, the attitude of the population to the formal information available were carried out in the strong radiation control areas and in the regions not polluted by radioactive fallout. Before the accident 71.6% of the population were not aware of real danger of radiation for health. During the accident and after it, mass media were the main source of information on the consequences of the accident and the effect of radiation (71.1%). 38% of the information was provided by scientists and specialists. 89.6% of the persons interviewed experience anxiety whatever the intelligence available. Only 13.4% of those who live in the areas polluted by radionuclides feel well. The low self-estimation of the health status, the high level of anxiety together with the deficiency of radiation and hygienic intelligence favour the forcing of the social and psychological tension and reduce the effectiveness of the whole complex of measures carried out in the areas polluted with radionuclides.

Accidents↗

Medulloblastoma: conventional radiation therapy in comparison to chemo radiation therapy in the post-operative treatment of high-risk patients.

UNLABELLED: The aim of this study is to assess treatment results of 48 pediatric high-risk medulloblastoma cases that were treated by surgery, radiotherapy with or without chemotherapy. The impact of adjuvant combination chemotherapy on treatment results will be assessed. Forty-eight cases of pediatric high-risk medulloblastoma treated from July 2001 to July 2004 were randomized into two groups. The first (group I) included 21 patients who received postoperative craniospinal radiation therapy (36Gy+boost 20Gy to the posterior fossa). The second (group II) included 27 cases who received postoperative combination cranio-spinal radiation therapy (with the same dose as the first group) and chemotherapy (vincristine, etoposide, cisplatin). Both groups were compared as regards overall survival (OS), disease free survival (DFS), response rate and treatment toxicity. In-group I, complete remission (CR) was achieved in 71.4% of the cases; partial remission (PR) in 14.3% of the patients; stationary disease (SD) in 14.3% and none of the cases suffered from progressive disease. The three-year OS was 69.5% and the three-year DFS was 61.3%. In-group II, CR was achieved in 59.3% of the cases; PR in 3.7%; SD in 3.7% and PD in 37.3% of the cases. The three-year OS was 48.4% and the 3-year DFS was 48.9%. Regarding acute treatment toxicity in group I, nine patients (31.5%) developed grade I myelo-suppression and seven cases (24.5%) developed grade II myelo-suppression with three to five days treatment interruption. Whereas in group II, 13 patients (45.5%) developed grade I myelosuppression and seven cases (24.5%) developed grade II myelo-suppression requiring interruption of treatment for a period ranging from five to seven days with spontaneous recovery. In group I no other acute toxicity was recognized, whereas in group II other toxicities related to chemotherapy were noticed. For example, three patients (11%) developed peripheral neuritis during the course of treatment and two patients (7%) developed renal impairment, which responded to medical treatment. Late treatment toxicity, manifested as reduction in intelligence quotient (IQ), was noticed, which makes conventional treatment of medulloblastoma unsatisfactory. In group I; 13 patients (62%) suffered a reduction of 8-20% in IQ in comparison to their normal siblings, whereas in Group II; 13 patients (48%) developed a reduction in IQ ranging from 12-21%. CONCLUSION: The current treatment of medulloblasotma has a detrimental effect on long-term survivors. Whereas acute toxicity is considered mild and tolerable, late toxicity regarding diminution in IQ makes current treatment unsatisfactory because of the long-term mental disability of the cured patients. We believe that, the poorer outcome in the chemo-radiation group was due to the treatment interruption during radiation therapy caused by myelosuppression since the incidence of myelosuppression was higher in the chemo-radiation group and the recovery time was longer.

Antineoplastic Combined Chemotherapy Protocols↗

Radiation therapy alone versus radiation therapy and chemotherapy in the management of Hodgkin's disease.

Forty-four patients with histologically proven Hodgkin's disease underwent initial treatment with extended-field radiation therapy. Nineteen of these patients also received combination chemotherapy. For analysis, patients were assigned to three treatment groups: group 1 received radiation therapy only (25 patients); group 2 received combination chemotherapy followed by consolidative (low-dose extended-field) radiation therapy; and group 3 was treated with alternate chemotherapy and radiation therapy using the sandwich technique. The actuarial 5-year disease-free survival rates were 83% (group 1), 83% (group 2), and 100% (group 3). The overall actuarial survival rates were 96% (group 1), 92% (group 2), and 100% (group 3). No factor was identified as being of prognostic value in predicting relapse. We conclude that extended-field radiation therapy delivered in this manner is a safe and effective approach to the initial management of Hodgkin's disease.

Adolescent↗

[Change in the aggregation ability of rabbit thymocytes under the combined effect of UV-radiation and extremely high frequency radiation].

The number of thymocytes, which have ability to aggregate with homologous erythrocytes, increases under action of the 254 nm UV-radiation at low fluences of 100-350 J/m2 similar action of ultra high frequency (UHF) radiation (46.12 GHz). The number of the active cells decreases during their incubation in the dark after irradiation, i.e. the inactivation after-effect is produced by UV-radiation. The thymocyte inactivation by UV-radiation at high fluences is enhanced if the cell suspension is preliminary irradiated with UHF-radiation at low intensity.

Animals↗

[Easy graphical display of beam directions in three-dimensional converging radiation therapy: proposal for a radiation map].

In stereotactic radiosurgery, non-coplanar isocentric beams are employed to concentrate the dose distribution on the planning target volume (PTV). However, the directions of incident beams must be determined with great care by using a digitally reconstructed beam's eye view (BEV) to prevent the irradiation of organs at risk. We present a new method of 2-dimensional graphical representation (radiation map) to facilitate the understanding of 3-dimensional relationships between incident beams and critical organs. After determining the isocenter and beam diameter, beam directions and critical organs are projected onto the imaginary sphere centered on the isocenter. The coordinate of the beam directions and the organs at risk can be expressed by latitude and longitude on the sphere. The contours of the organs at risk are displayed with a margin of the the radius of the radiation beam. Mirror images of the critical organs are also displayed to prevent irradiation by the opposing beams. The radiation map could be produced within 5 minutes using a workstation. Radiation maps, like DVH, will be very useful in the evaluation of radiation treatment planning.

Radiosurgery↗

Effects of exposure to external ionizing radiation on cancer mortality in nuclear workers monitored for radiation at Rocketdyne/Atomics International.

BACKGROUND AND METHODS: A retrospective cohort study was conducted to estimate the effects of low-level exposure to external (penetrating) radiation on cancer mortality among 4,563 workers monitored for external radiation between 1950 and 1993 at a nuclear research and production facility in Southern California. RESULTS: Of the 875 deaths that occurred before 1995, 258 were due to cancer as the underlying cause. External comparisons of male subjects with the U.S. white male population indicated that the workers had lower rates of dying from all causes and all cancers, but a higher rate of dying from leukemia. Internal comparisons of workers exposed at different dose levels, using risk-set analyses with adjustment for confounders, demonstrated an increased mortality rate in workers exposed to 200 mSv for hemato- and lymphopoietic cancers and for lung cancer. Mortality rates for total cancers and "radiosensitive" solid cancers increased monotonically with cumulative radiation dose, but no trends were observed for "nonradiosensitive" cancers. CONCLUSIONS: Despite possible residual confounding and low precision for estimating effects on specific cancers, these findings indicate that chronic, low-level radiation exposure may have more generalized carcinogenic effects than have been observed in most previous investigations. Such effects may have become evident as a result of the relatively long follow-up period in the present study.

Adult↗

Effects of radiation fractionation on four squamous cell carcinoma lines with dissimilar inherent radiation sensitivity.

The effect of radiation fractionation was investigated using a new 96-well-plate clonogenic assay in four squamous cell carcinoma lines. Earlier experiments had shown that two of the cell lines (UT-SCC-1A and UM-SCC-14A) were inherently relatively sensitive to irradiation, and two (UM-SCC-1 and UM-SCV-1A) relatively resistant. All of the four carcinomas from which the cell lines were established had poor clinical outcome. The radiation doses were given as a single exposure, or split into two or three equal fractions with a 24-h interval. The two inherently sensitive cell lines showed enhanced survival after radiation fractionation as compared with a single dose, whereas the resistant cell lines did not. The result suggests that both the inherent resistance of cancer cells to irradiation and the repair of sublethal radiation damage may lead to treatment failure, and that shortening of the total irradiation time may overcome cancer cell recovery between fractions in some, but not in all carcinomas.

Carcinoma, Squamous Cell↗

[Electrosmog, cellular phones, sunbeds etc. -- adverse health effects from radiation? Health aspects of non-ionizing radiation].

This review supplies a survey of the three physical influences, i. e. UV radiation, high-frequency electromagnetic fields of radio telephone systems and other wireless radio applications as well as low-frequency fields of electric power supply. The exposure to UV radiation must be considered to be by far the highest health risk. The annual rate of about 2000 deaths from skin cancer in Germany, mainly caused by extensive exposure to solar UV radiation, demands protective measures. Teaching reasonable behaviour is the supreme issue. Recommended protective measures in the order of their effectiveness are protection by adaptation of behaviour, by clothes, sun hats and sunglasses as well as by sun creams. Children are the most important target group. With regard to UV tanning appliances it is recommended not to use artificial UV radiation for cosmetic purposes because of the related health risks. For the assessment of health impairments caused by exposure to electromagnetic fields, direct field reactions due to induced electric body currents, reactions on the surface of the body or heating effects should be separated from indirect field reactions (e. g. electric shocks and burns) due to contact currents or interference with electronic body aids and implants. Risk assessment has led to recommendations of threshold values which-in agreement with international research results-exclude all impairments of health caused by direct field reactions scientifically proven to date. Contrary to public concerns, which are mostly related to base transmitters of radio telephone systems, exposure due to handheld radio telephones (cellular phones) should rather be considered from the viewpoint of precautionary health protection, since it is more likely that their use can lead to high exposure of the user. Due to the protective measures provided so far and observance of the threshold values based on scientific results, exposures do not lead to health impairments-not even in children. Because of the introduction of new technologies more portable devices are to be expected that may be operated near the body. This will further increase the exposure of people to high-frequency electromagnetic fields.

Cell Phone↗

Molecular mechanisms of radiation carcinogenesis and the linear, non-threshold dose response model of radiation risk estimation.

Recent research in molecular radiation carcinogenesis is reviewed with the specific aim of exploring the implications this research may have on the dose response relationship of radiation-induced cancer at low doses and low dose rates. It is concluded that the linear non-threshold dose response hypothesis may be used in radiation protection planning as a simple, convenient method to optimize procedures and regulations, but should not be mistaken as a stringent scientific conclusion directly derived from the present state of knowledge of the processes involved in radiation carcinogenesis.

DNA Repair↗

Radiation induced secretion of surfactant from cell cultures of type II pneumocytes: an in vitro model of radiation toxicity.

The pathogenesis of pneumonitis and fibrosis secondary to lung irradiation is incompletely understood. The role of the type II alveolar epithelial pneumocyte in these processes has been under investigation. The type II pneumocyte has been shown in vivo to respond to radiation induced injury with release of pulmonary surfactant. The effect of irradiation on cell cultures of type II pneumocytes was studied to determine if this could be reproduced in vitro. Type II pneumocytes were found to release surfactant material with a threshold of radiation dose between 1000 and 1500 rad. This is similar to the dosage range over which the same effect has been demonstrated in vivo. Experimental results support the concept that the release of surfactant is not due to either cell disruption or non-specific release of phospholipid from cell membranes. Irradiation appears to trigger membrane receptor mediated surfactant release. In addition, irradiation abolishes the ability of cells to subsequently respond to a physiologic agonist, suggesting radiation induced damage to the secretory mechanism. These studies establish that surfactant release in response to irradiation in vivo is a direct effect on type II pneumocytes. Cell cultures of type II pneumocytes can serve as a laboratory model of lung cell radiation toxicity.

Animals↗

Acute radiation-induced pulmonary damage: a clinical study on the response to fractionated radiation therapy.

Acute radiation-induced pulmonary damage can be a significant cause of morbidity in radiation therapy of the thorax. A prospective, clinical study was conducted to obtain dose-response data on acute pulmonary damage caused by fractionated radiation therapy. The endpoint was a visible increase in lung density within the irradiated volume on a computed tomographic (CT) examination as observed independently by three diagnostic radiologists. Fifty-four patients with various malignancies of the thorax completed the study. CT chest scans were taken before and at preselected times following radiotherapy. To represent different fractionation schedules of equivalent biological effect, the estimated single dose (ED) model, ED = D X N-0.377 X T-0.058 was used in which D was the average lung dose within the high dose region in cGy, N was the number of fractions, and T was the overall treatment time in days. Patients were grouped according to ED and the percent incidence of pulmonary damage for each group was determined. Total average lung doses ranged from 29.8 Gy to 53.6 Gy given in 10 to 30 fractions over a range of 12 to 60 days. Five patient groups with incidence ranging from 30% (ED of 930) to 90% (ED of 1150) were obtained. The resulting dose-response curve predicted a 50% incidence level at an ED value (ED50) of 1000 +/- 40 ED units. This value represents fractionation schedules equivalent to a total average lung dose of 32.9 Gy given in 15 fractions over 19 days. Over the linear portion of the dose-response curve, a 5% increase in ED (or total dose if N and T remain constant), predicts a 12% increase in the incidence of acute radiation-induced pulmonary damage.

Adolescent↗

Repair of ionizing-radiation damage in the radiation resistant bacterium Deinococcus radiodurans.

Deinococcus radiodurans is extremely resistant to the lethal and mutagenic effects of ionizing-radiation and many other physical and chemical agents that damage DNA. This resistance is known to be due to D. radiodurans' extremely proficient DNA repair processes. However, little is known about the precise mechanisms employed by this organism to achieve its efficient repair. In the past two years there has been substantial progress in studies on the repair and tolerance of ionizing radiation damage. Areas of progress include: 1) studies on the importance of the deinococcal recA-gene in repair; 2) characterization of a large number of new ionizing radiation-sensitive strains; 3) newly discovered genetic loci with novel repair-related mutational phenotypes; 4) demonstration of efficient interplasmidic and interchromosomal recombination occurring postirradiation; and 5) recent speculations on the mechanisms of radiation resistance and the driving forces of natural selection for DNA damage resistance in D. radiodurans.

DNA Damage↗

The radiation-induced changes in rectal mucosa: hyperfractionated vs. hypofractionated preoperative radiation for rectal cancer.

PURPOSE: The purpose of the study was the qualitative and quantitative evaluation of acute radiation-induced rectal changes in patients who underwent preoperative radiotherapy according to two different irradiation protocols. PATIENTS AND METHODS: Sixty-eight patients with rectal adenocarcinoma underwent preoperative radiotherapy; 44 and 24 patients underwent hyperfractionated and hypofractionated protocol, respectively. Fifteen patients treated with surgery alone served as a control group. Five basic histopathologic features (meganucleosis, inflammatory infiltrations, eosinophils, mucus secretion, and erosions) and two additional features (mitotic figures and architectural glandular abnormalities) of radiation-induced changes were qualified and quantified. RESULTS: Acute radiation-induced reactions were found in 66 patients. The most common were eosinophilic and plasma-cell inflammatory infiltrations (65 patients), erosions, and decreased mucus secretion (54 patients). Meganucleosis and mitotic figures were more common in patients who underwent hyperfractionated radiotherapy. The least common were the glandular architectural distortions, especially in patients treated with hypofractionated radiotherapy. Statistically significant differences in morphologic parameters studied between groups treated with different irradiation protocols were found. CONCLUSION: The system of assessment is a valuable tool in the evaluation of radiation-induced changes in the rectal mucosa. A greater intensity of regenerative changes was found in patients treated with hyperfractionated radiotherapy.

Adenocarcinoma↗

Efficacy and tolerability of concurrent weekly low dose cisplatin during radiation treatment of localised muscle invasive bladder transitional cell carcinoma: a report of two sequential Phase II studies from the Trans Tasman Radiation Oncology Group.

BACKGROUND AND PURPOSE: To determine the feasibility, toxicity, and clinical effectiveness of concurrent weekly cisplatin chemotherapy in conjunction with definitive radiation in the treatment of localised muscle invasive bladder cancer. PATIENTS AND METHODS: In January 1997 the Trans Tasman Radiation Oncology Group embarked on a Phase II study (TROG 97.01) of weekly cisplatin (35 mg/m(2) x 7 doses) plus radiation to a dose of 63 Gy over 7 weeks. Following an interim toxicity analysis, the dose intensity of cisplatin was reduced to 6 cycles and the radiation schedule changed to 64 Gy over 6.5 weeks leading to the second study (TROG 99.06). A total of 113 patients were enrolled. RESULTS: Acute grade 3 urinary toxicity occurred in 23% of the patients. Acute grade 4 pelvic toxicity was not seen. Thirty-eight patients (33%) experienced grade 3 or 4 cisplatin related toxicities with 15 patients (12%) requiring significant dose modification. The reduced dose intensity in Study 99.06 improved tolerability. Incidence of significant late morbidity was low (6%). Seventy-nine patients (70%) achieved complete remission at the 6 month cystoscopic assessment. Local invasive recurrence was seen in 11 of the 79 patients (14%). In 18 patients (16%) isolated superficial TCC/CIS were detected (6 months and beyond). The local control rate was 45% with a functional bladder being retained in 69 of the 113 patients (61%). RFS and DSS at 5 years were 33% and 50%, respectively. CONCLUSION: Our two sequential Phase II studies have shown that concurrent chemoradiation using weekly cisplatin in the management of localised invasive bladder TCC is feasible and reasonably well tolerated. This approach is currently being investigated further in a randomised study.

Aged↗