Implementation of meta-analysis approach, comparing conventional radiotherapy, and proton beam therapy treating head and neck cancer

Introduction: Radiation therapy is commonly used in the treatment of head and neck cancer in both the definitive and postoperative settings. Proton therapy, due to its intrinsic physical properties, has the ability to reduce the integral dose delivered to the patients while maintaining highly conformal target coverage Materials and Methods:.A literature search was performed on scientific databases, and Preferred Reporting Items for Meta-Analyses guidelines were followed to compute results. Only original studies were selected. Selected studies were used to extract some proposed data for comparison, dosimetry, site, complications, and survival. Results: Proton beam therapy technology can be used against the conventional radiotherapy and shows satisfactory results. Yet conventional therapy is not less advantageous considering the amount of work available for any cross interpretations. Conclusion: Comparative preplanning could be beneficial considering multiple therapies for ruling out the best treatment outcomes that could be expected

Dosimetric comparison with conventional radiation therapy and intensity modulated radiation therapy for locally advanced laryngeal carcinoma / 实用肿瘤学杂志

Obejctive To compare the differences between conventional radiation therapy (3DCRT) and intensity modulated radiation therapy( IMRT) for locally advanced laryngeal carcinoma patients by ECLIPSE treat -ment planning system.Methods Six locally advanced laryngeal carcinoma patients ′treatment plans were de-signed as IMRT and 3DCRT according to ECLIPSE treatment planning system ,respectively.The following values were measured,such as V95%、D5%、D95%、Dmin and D mean of the target volume,and the D50,D33,D5, Dmax and Dmean of normal tissues.Results The dose coverage rate of GTV and GTVnd in the IMRT plan was compared to ECLIPSE treatment planning system with no statistical differences.However, there were obvious difference in CTV and some normal tissues.Conclusion Both IMRT and 3DCRT have good coverage to primary tumor and metastatic lymph nodes.IMRT can spare the parotid from high dose irradiation.

Spinal cord biological safety comparison of intensity modulated radiotherapy and conventional radiation therapy / 中华放射医学与防护杂志

Objective To compare the spine intensity modulated radiation therapy (IMRT) and the conventional radiation therapy on the beagle spinal cord neurons,in order to prove the biological safety of IMRT of the spinal cord.Methods Twelve selected purebred beagles were randomly divided into 2 groups.A beagle clinical model of tumor was mimiced in the ninth and tenth thoracic vertebrae.Then the beagles were irradiated by 2 different models of intensity modulated radiotherapy and conventional radiation therapy,with the total irradiation doses of 50 and 70 Gy.The samples of spinal cord were taken out from the same position of the nine and tenth thoracic vertebrae at the third month after radiation.All the samples were observed by the electron microscope,and the Fas and HSP70 expression in spinal cord neurons were evaluated by immunohistochemistry method.Terminal deoxynucleatidyl transferase mediated dUTP nick and labeling (TUNEL) technique was used to examine the apoptotic cells in the spinal cord.Results The neurons in the spinal cord of IMRT group were mainly reversible injury,and those in the conventional radiation therapy were mainly apoptosis.Compared with the conventional radiation therapy group [50 Gy group,(7.3±1.1)% ;70 Gy group,(11.3 ±.4)%],the apoptosis rate of the spinal cord neurons of the intensity modulated radiotherapy group[50 Gy group,(1.2 ±0.7)%;70 Gy group(2.5 ±0.8)%] was much lower[(50 Gy group,t＝0.022,P＜0.05;70 Gy group,t＝0.017,P＜0.05)].The expression levels of Fas in the IMPT group(50 Gy group,4.6 ±0.8;70 Gy group,7.4 ±1.1)were also much lowerthan those in the other group(50 Gy group,15.1 4-6.4;70 Gy group,19.3 ±7.6.50 Gy group,t＝0.231,P＜0.05;70 Gy group,t:0.457,P＜0.05),while the expression levels of HSP70 in the IMPT group(50 Gy group,9.1 ±0.8;70 Gy group,7.3±1.4)were much higher than those in the conventional radiation therapy group(50 Gy group,2.1 ±0.9;70 Gy group,1.7±0.3;50 Gy group,t＝0.153,P＜0.05;70 Gy group,t＝0.223,P＜0.05).The expression of Fas/HSP70 was positively correlated with the apoptosis rate of the spinal cord neurons(r＝0.996,t＝1.14.P＜0.05).Conclusions The late radiotherapy response of the spinal cord neurons was obviously observed on the third month.Comparison of the morphology and apoptosis rate of the spinal cord neurons after radiotherapy,the expression of Fas and HSP70 indicated that the biological safety in the 1MRT might be much better than that the conventional radiation therapy.

The Effect of External Radiation Therapy for Intracranial Arteriovenous Malformation: Conventional Radiation Therapy vs Stereotactic Radiosurgery / 대한치료방사선과학회지

From February 1987 through July 1990, the seventeen cases of inoperabelintracranial arteriovenous malformation (AVM) were treated using 6 MV linear accelerator at the Division of Therapeutic Radiology, Kang Nam St. Mary's Hospital. Of seventeen cases, fourteen were male and three were female. Ages ranged from 10 to 51 years (median age of 26 years). The main symptoms were headache, epilepsy and hemiparesis in decreasing order of frequency. The middle cerebral artery is the most common origin of the feeding vessel (41.2%). Four were treated by conventionally fractionated radiation therapy (CRT), thirteen were treated by stereotactic radiosurgery (RS). Duration of follow-up study, two of four CRT group showed minimal response. Of thirteen cases of RS group, two (15.4%) showed complete response, five (38%) partial response, two (15.4%) minimal response and four (30.7%) no response by the same assessment. There was no statistical significance in terms of follow-up period (p=0.22), size of lesion (p=0.82) and treated dose (p=0.65). Further accumulation of experience s recommended with proper case selection and sufficient follow-up period.