Effects of Beam Startup Characteristics on Dose Delivery Accuracy at Low Monitor Units in Step-and-Shoot Intensity Modulated Radiation Therapy

Intensity modulated radiation therapy (IMRT) is a highly accurate technique that is usually implemented in either dynamic or step-and-shoot fashion with many segments each having low monitor units (MUs). The present study evaluated the effects of beam startup characteristics on the dose delivery accuracy for each segment at low MUs for step-and-shoot IMRT with an Elekta Precise accelerator at the highest dose rates. We used a two-dimensional semi-conductor detector for the dose measurements. The field size of each segment was assumed to be 20 ×20 cm2 and each segment was set to deliver 1 - 10 MUs. Our results show a variation in dose delivery accuracy between segments for the same IMRT beam, which can be attributed to the beam startup characteristics. This variability is attributed to the changes in the transient changes in the temperatures of the electron gun filament and the magnetron. That is, the transient increase in the temperature of the filament leads to increasing doses with time and that of the magnetron leads to decreasing doses with time during the first few MUs.

Hepatocyte growth factor gene therapy prevents radiation-induced liver damage

AIM: To transfer human HGF gene into the liver of rats by direct electroporation as a means to prevent radiationinduced liver damage.METHODS: Rat whole liver irradiation model was accomplished by intra-operative approach. HGF plasmid was injected into liver and transferred by electroporation using a pulse generator. Control rats (n = 8) received electrogene therapy (EGT) vehicle plasmid and another 8rats received HGF-EGT 100 μg 48 h before WLIR.Expression of HGF in liver was examined by RT-PCR and ELISA methods. Apoptosis was determined by TUNEL assay. Histopathology was evaluated 10 wk after whole liver irradiation.RESULTS: Marked decrease of apoptotic cells and downregulation of transforming growth factor-beta 1 (TGF-β1)mRNA were observed in the HGF-EGT group 2 d after liver irradiation compared to control animals. Less evidence of radiation-induced liver damage was observed morphologically in liver specimen 10 wk after liver irradiation and longer median survival time was observed from HGF-EGT group (14 wk) compared to control rats (5 wk). (P = 0.031).CONCLUSION: For the first time it has been demonstrated that HGF-EGT would prevent liver from radiation-induced liver damage by preventing apoptosis and down-regulation of TGF-β1.

A model to predict the risk of lethal nasopharyngeal necrosis after re-irradiation with intensity-modulated radiotherapy in nasopharyngeal carcinoma patients

Background:For patients with nasopharyngeal carcinoma(NPC) who undergo re-irradiation with intensity-modulated radiotherapy(IMRT),lethal nasopharyngeal necrosis(LNN) is a severe late adverse event.The purpose of this study was to identify risk factors for LNN and develop a model to predict LNN after radical re-irradiation with IMRT in patients with recurrent NPC.Methods:Patients who underwent radical re-irradiation with IMRT for locally recurrent NPC between March 2001 and December 2011 and who had no evidence of distant metastasis were included in this study.Clinical characteristics,including recurrent carcinoma conditions and dosimetric features,were evaluated as candidate risk factors for LNN.Logistic regression analysis was used to identify independent risk factors and construct the predictive scoring model.Results:Among 228 patients enrolled in this study,204 were at risk of developing LNN based on risk analysis.Of the 204 patients treated,31(15.2%) developed LNN.Logistic regression analysis showed that female sex(P = 0.008),necrosis before re-irradiation(P = 0.008),accumulated total prescription dose to the gross tumor volume(GTV) ≥ 145.5 Gy(P = 0.043),and recurrent tumor volume >25.38 cm3(P = 0.009) were independent risk factors for LNN.A model to predict LNN was then constructed that included these four independent risk factors.Conclusions:A model that includes sex,necrosis before re-irradiation,accumulated total prescription dose to GTV,and recurrent tumor volume can effectively predict the risk of developing LNN in NPC patients who undergo radical re-irradiation with IMRT.

Secondary and activated X(γ)radiation of SPHIC particle therapy facility

We report the secondary X(γ)radiation from the accelerator in a normal operating state and activated X(γ)radiation from the accelerator devices when the accelerator stops operating in the cancer treatment facility of the Shanghai Proton and Heavy Ion Center(SPHIC).These radiation measurements show us the structural radiation distribution along the beam lines and devices inside the accelerator room when the beam is on and off and can support the radiation protection design of the accelerator facility used for cancer treatment and help evaluate the accumulated radiation dose in the case of an emergency,such as a personal safety system failure or a radiation accident.The radiation dose rate measured in this facility shows that the facility is safe from the radiation protection point.After shooting the quality assurance(QA)beam,the radiation dose rate in the treatment room was also measured to investigate the radiation dose space distribution and decay time dependence.In addition,the time period before safely entering the treatment room after determining the shooting of the QA beam is recommended to be approximately 5 min.

Molecular features of gastroenteropancreatic neuroendocrine carcinoma: A comparative analysis with lung neuroendocrine carcinoma and digestive adenocarcinomas

Objective: There is an ongoing debate about whether the management of gastroenteropancreatic(GEP)neuroendocrine carcinoma(NEC) should follow the guidelines of small-cell lung cancer(SCLC). We aim to identify the genetic differences of GEPNEC and its counterpart.Methods: We recruited GEPNEC patients as the main cohort, with lung NEC and digestive adenocarcinomas as comparative cohorts. All patients undergone next-generation sequencing(NGS). Different gene alterations were compared and analyzed between GEPNEC and lung NEC(LNEC), GEPNEC and adenocarcinoma to yield the remarkable genes.Results: We recruited 257 patients, including 99 GEPNEC, 57 LNEC, and 101 digestive adenocarcinomas.Among the mutations, KRAS, RB1, TERT, IL7R, and CTNNB1 were found to have different gene alterations between GEPNEC and LNEC samples. Specific genes for each site were revealed: gastric NEC(TERT amplification),colorectal NEC(KRAS mutation), and bile tract NEC(ARID1A mutation). The gene disparities between small-cell NEC(SCNEC) and large-cell NEC(LCNEC) were KEAP1 and CDH1. Digestive adenocarcinoma was also compared with GEPNEC and suggested RB1, APC, and KRAS as significant genes. The TP53/RB1 mutation pattern was associated with first-line effectiveness. Putative targetable genes and biomarkers in GEPNEC were identified in22.2% of the patients, and they had longer progression-free survival(PFS) upon targetable treatment [12.5 months vs. 3.0 months, HR=0.40(0.21-0.75), P=0.006].Conclusions: This work demonstrated striking gene distinctions in GEPNEC compared with LNEC and adenocarcinoma and their clinical utility.

Analysis of The Effect of Bundled Nursing Intervention on Lung Cancer Patients with a High Risk of PICC-Related Thrombosis

Objective: To explore the effect of bundled nursing intervention on lung cancer patients with a high risk of PICC-related thrombosis. Methods: Eighty-six PICC patients were selected and randomly divided into a control group and an observation group of 43 patients each. The control group received general nursing care and the observation group received bundled nursing intervention based on the control group. The occurrence of venous thrombosis, quality of life score, Zung self-rating depression scale (SDS) score, self-rating anxiety (SAS) score, and nursing satisfaction after treatment were compared between the two groups. Results: The incidence rate of PICC-related venous thrombosis in the observation group (2/4.652%) was lower than that of the control group (13/30.231%) after nursing intervention (P < 0.05). After the intervention, the quality-of-life scores of the observation group were higher than those of the control group (P < 0.001). After the intervention, the SDS and SAS scores of the observation group were lower than those of the control group (P < 0.001). The nursing satisfaction rate of the observation group (41/ 4.652%) was higher than that of the control group (35/18.604%) (P < 0.05). The difference is statistically significant. Conclusion: In the care of lung cancer patients with a high risk of PICC-related thrombosis, bundled nursing care achieved better results.

Postoperative radiotherapy in resected non-small cell lung cancer:The never-ending story

This manuscript collects in a joint and orderly manner the existing evidence at the present time about postoperative treatment with radiotherapy in non-small cell lung cancer.It also systematically reviews the current evidence,the international recommendations in the most relevant guidelines,the most controversial aspects in clinical and pathological staging,the specific technical aspects of radiotherapy treatment,and also collects all the potential risk factors that have been postulated as significant in the prognosis of these patients,evaluating the possibility of segmenting a particularly sensitive subpopulation with a high risk of relapse on which an adjuvant treatment with radiotherapy could have an impact on their clinical evolution.Finally,currently active trials that aspire to provide more evidence on this topic are reviewed.

Enhancement of leukocyte adhesion after percutaneous irradiation in rats with hepatocellular carcinoma

AIM: To evaluate the effects of percutaneous radiation on leukocyte-endothelium interaction (LEI) in experimental hepatocellular carcinoma (HCC). METHODS: Twelve ACI rats underwent HCC-inoculation, six of which on day 12 received low-dose external radiation and six did not. After 12 h intravital microscopy was performed. RESULTS: LEI was significantly reduced in tumor tissue. However,irradiation of liver sinusoids and tumor tissue with 6 Gy led to a significant activation of leukocyte adhesion in the tumor with a marked increase of the proinflammatory cytokine TNF-α. CONCLUSION: The findings indicate that the immune-logical tumor-endothelial barrier can be overcome by external irradiation.

The Influence of Different Single Radiation Dose on Delayed Growth of Transplanted Tumor in Athymic Mouse

OBJECTIVE To reveal the biological effects and effective dosage in radiotherapy model which applies high single-dose irradiation by animal experiment. METHODS We inoculated subcutaneouly human pancreatic carcinoma cell line （MIA PaCa-2） in the lateral of the right lower extremity of the athymic mouse to grow transplantation tumor. While the median diameter of transplantation tumor reached 10 mm approximately, the animals were randomly divided into 7 groups （6 animals per group） and irradiation by different dose in one fixed with consciousness for fraction （0, 2, 5, 10, 17, 25, 35 Gy）. All were kept on to be bred for observation of the change in gross tumor volume, calculation of delayed growth time and delayed growth curve. RESULTS With increased dose per fraction, cutaneous reaction on the neoplasma surface of the animal, which was mainly moist yellow effusion was more and more severe. When dosage is less than 10 Gy, all animals showed similar effects, that＇s the delayed tumor growth was not obvious. Tumors receiving more than 10 Gy in one fraction showed very good biological effect and the delayed tumor growth was obviously related to dosage. The difference in delayed tumor growth between the 2 groups was statistically significant. The delayed tumor growth time in 10, 17, 25 Gy group was respectively 3 weeks, 6 weeks and more. CONCLUSION The biological effect of the model which applies high single-dose irradiation （more than 10 Gy in one fraction） was very good. The effect of delayed tumor growth was obviously related to the dosage after transplantation tumor was radiated. Because of its higher dose per fraction and biological effects, the model of high single-dose irradiation can get better clinical effects.

Initial Approach to the Cellular Irradiation Injury of Human Pancreatic Carcinoma Cell Line MIA PaCa-2 by High Dose per Fraction

OBJECTIVE To investigate an initial approach of radiotherapy, which produces cellular radiation injury by high dose in one fraction. METHODS Human pancreatic carcinoma cell line MIA PaCa-2, was cultivated and divided into 5 groups： 0, 2, 5, 10, 17 Gy. Cultivated cells were irradiated by 6MV-X ray in one fraction. Analysis were done as follows： comet assay, which assessed the level of DNA damage in the treated cells right after the cell was irradiated, flow cytometry, which was performed at 0, 6, 12, 24, 36 h after the cell line treated to ladder, which quantitatively asses changes of its cell cycle, DNA assessed the degree of DNA injury after 6 and 12 h, and histological examination, which analyzed cellular morphology after 24 h. RESULTS （1） After X-ray irradiated, the morphological change of human pancreatic carcinoma cell line （MIA PaCa-2） was mainly swelling. （2） When the dose of radiation was lower than 10 Gy, increasing the dose could greatly improve cell necrosis, apoptosis and blockage of cell cycle in GJM phase, which was consistent with the theory of radiation biology. （3） When radiation dose was more than the 10 Gy, the peak of apoptotic necrosis appeared strong and early. （4） The degree of DNA injury was also related to the dose of radiation therapy and most obvious in the 10 Gy group and not so obvious in the 17 Gy group. （5） When dose was less than 10 Gy, DNA ladder was a single electrophoretic band; in the 10 Gy group, the electrophoresis showed a multiple ladder band; when dose was more than 10 Gy, a vague and irregular band appeared on the electrophoresis. CONCLUSION Oncotic necrosis may be the main cell death style when dose per fraction is high, which differs from conventional dose fraction radiation therapy.

Intrathoracic latissimus dorsi muscle transposition: a reliable technique for prevention of bronchopleural fistula developing after extrapleural pneumonectomy and external beam radiotherapy in malignant pleural mesothelioma

Objective: Bronchopleural fistula (BPF) is a life threatening complication after pneumonectomy. Extra thoracic skeletal muscle transposition especially latissimus dorsi muscle flap (LDMF) had been used to prevent this complication. The aim of this study was to assess the effectiveness of LDMF in preventing BPF developing after extrapleural pneumonectomy (EPP) and external radiation therapy in malignant pleural mesothelioma (MPM). Methods: Between May 1999 and Dec. 2008, 37 patients with MPM were operated upon by EPP using LDMF prophylactically to reinforce the bronchial stump, and then received external radiation therapy with or without postoperative chemotherapy. Results: The mean age of all patients was 46.7 (range 26-57) years. Twenty five patients were males and 12 patients were females. Twenty three patients had MPM of the right side and 14 patients had MPM of the left side. The peri-operative mortality was 2.7% and only few flap related postoperative morbidity were reported in the form of minor seroma and subcutaneous surgical emphysema. The median follow up was 17 (range 9-43) months. All cases completed their postoperative external radiation therapy with no reported cases of early or late BPF. Conclusion: Intrathoracic pedicled LDMF transposition is proved to be effective in prevention of BPF developing after EPP and external radiation therapy in MPM and it is advised to be a routine step in EPP in these cases and to use more sophisticated technique of postoperative external beam radiotherapy (3D conformal or IMRT) to minimize this complication.

STAGE IB, HA AND PROXIMAL IIB, CARCINOMA OF THE UTERINE CERVIX, TREATED BY IRRADIATION ALONE OR IN COMBINATION WITH SURGERY

This is a report of a nonrandomized comparison of treatment results of 139 patients with stage IB, HA and proximal IIB carcinoma of the uterine cervix treated by radiation alone and 113 treated with a combination of radiation and surgery. The five-year tumor free acturial survival for the patients with stage IB either with irradiation alone (RT) or combined with surgery (RS) was approximately 87%. For stage Ⅱ the tumor free actuarial five-year survival 79% with patients of RS, and 76% with RT. In the 113 patients treated with RS there were 18 (16%). In the 139 patients treated by RT there were 18 (13%) recurrences of pelvic, 4 local recurrences, 11 combined with parametrial, and free parametrial recurrences. There was no significant difference in the survival and recurrence rate of the patients treated with either method. Major complications were comparable in both groups (RT approximately 25% and RS approximately 10%), but 2/3 of those complications recovered without sequelae. The most frequent minor complication in the patients treated with RT was rectosigmoiditis.

Monitoring of Tumor Response to Neoadjuvant Radio-Chemotherapy of Esophageal Carcinoma by F-18-FDG-PET

Introduction: For clinical assessment of neoadjuvant radiochemotherapy of esophageal cancer reliable in-vivo methods are necessary. Therefore, the capabilities of F-18-Fluorodesoxyglucose-PET in comparison to histomorphological grading of tumor regression were studied. Methods: In 33 patients with locally advanced esophageal carcinoma (uT3, uN0-1, cM0) F-18-FDG-PET was performed before and 2 weeks after radiochemotherapy. All tumors were resected by transthoracic en-bloc esophagectomy 3–4 weeks after induction therapy. A subgroup of 11 patients underwent weekly PET scan during neoadjuvant therapy. PET was performed in a dedicated scanner 1.3 h after administration of 370 MBq F-18-FDG. Data analysis based on maximum SUV data derived from individual regions of interest in pre- and posttherapeutic images. PET data were compared to histomorphological grading parameters for tumor regression whithin the resected tissues. Results: The comparison of histopathological tumor regression after neoadjuvant therapy and PET SUV di?erences showed a signi?cant χ2 P -value of 0.006. There was a signi?cant decrease 五笔字型计算机汉字输入技术 of the SUV data from 9.1±3.5 to 4.3±1.9 (P <0.0001). In therapy responders SUV was diminished by 59 % and in non-responders by 34 %. Longitudinal SUV measurement during neoadjuvant therapy showed a strong SUV decrease already after one and two weeks (P =0.021 and 0.003). Conclusion: The recent data of the FDG-PET follow-up after neoadjuvant therapy show that PET is able to predict therapy response. Longitudinal PET data advocate that it may be possible to recognize response also very early during radiochemotherapy.

Determining the efficacy of vitamin B12 mixed oral liquid in the treatment of radiation-induced esophagitis

Objective This study aimed to investigate the effects of vitamin B12 mixed oral liquid in the treatment of radiation-induced esophagitis in patients with esophageal cancer.Methods Seventy-five patients with esophageal cancer who met the enrollment criteria were randomly divided into the vitamin B12 mixed oral liquid group(39 patients in the study group)and the gentamicin mixed oral liquid group(36 patients in the control group).The effects of the two treatment methods on esophagitis grading,pain degree,body weight loss,and Karnofsky performance status(KPS)score in patients with radiation esophagitis were observed.Results In the control group,grade 1 radiation esophagitis accounted for 27.8%of the total patients,grade 2 accounted for 41.7%,and grades 3 and 4 accounted for 30.6%.In the vitamin B12 treatment group,grade 1 radiation esophagitis accounted for 66.7%of the total patients,grade 2 accounted for 25.6%,and grades 3 and 4 accounted for 7.7%;there was a significant difference between the vitamin B12 treatment group and control group(P<0.01).Similarly,pain caused by radiation esophagitis was significantly improved in the vitamin B12 group compared with the control group(P<0.05).After treatment,the average weight loss of the control group was(2.18±0.36)kg,while that of the vitamin B12 treatment group was(0.90±0.43)kg(P<0.05).The KPS scores of the vitamin B12 group were higher than those of the control group,which were 86.2±1.2 and 85.6±1.5,respectively,but there was no statistical difference(P>0.05).Conclusion Vitamin B12 mixed oral liquid can effectively reduce the severity of radiation esophagitis,relieve pain,improve patients’quality of life,and increase treatment compliance.

Unusual Case of Radiation Induced Balanitis after Chemoradiation for Upper Rectal Adenocarcinoma

Background: Penile toxicity after preoperative concurrent chemoradiation (CCRT) for rectal cancers is extremely rare and only two cases of phimosis and one case of recto-cavernosalfistula have been reported so far in literature. Preoperative CCRT for rectal cancer is given in prone position and with the support of belly board (BBD) to avoid small bowel toxicity. However, positional errors during rectal radiotherapy can lead to unexpected penile toxicity. Case Presentation: A 50-year-old Saudi male with diagnosed case of rectal adenocarcinoma stage cT3N1M0 was given preoperative CCRT 50.4 Gy in 28 fractions with three-dimensional conformal radiation therapy (3DCRT) in prone position using belly board with concurrent oral capecitabine 825 mg/2 twice a day. After the completion of CCRT, he complained of severe soreness, itching over glans penis and dysuria. Examination revealed grade 3 erythema, skin desquamation over glans penis (balanitis). Portal imaging of treatment revealed glans penis to lie within posterior radiation beam. A patient was assured and he recovered fully after local steroids and short course of antibiotics. Conclusion: Penile toxicity after CCRT for rectal cancer is extremely rare manifestation. Radiation oncologists and therapists must be aware of this rare side effect and must assure proper patient education and positioning during CCRT for rectal cancer.

Variations in Tomotherapy Beam Outputs: A Multiple-Institutional Investigation

This study aimed to determine variations in tomotherapy beam outputs at multiple institutions. Measurements were obtained at 22 radiotherapy institutions. The first parameter was the absolute dose to water (Dfmsrw, Qmsr) in the machine-specific reference field (fmsr), which indicated a static field in the tomotherapy reference conditions defined by the International Atomic Energy Agency (IAEA) study group. The second measured parameter was the difference between the measured and the planed doses in the intensity modulated radiotherapy (IMRT) verification plans, which were created using a solid phantom by the vendor during tomotherapy apparatus installation to adjust the beam output. The IMRT verification plan error at each institution was defined as the systematic error of the beam output;Dfmsrw, Qmsr was subsequently modified. The Dfmsrw, Qmsr values of four institutions with a modified energy fluence per ideal open time (EFIOT) were lower than the values at other institutions. The mean value of all institutions except those four was 0.994 ± 0.013 Gy (range: 0.974 Gy, 1.017 Gy). When the Dfmsrw, Qmsr value was corrected by the IMRT verification error, this variation decreased. In addition, the mean IMRT verification errors in the TomoDirectTM and TomoHelicalTM modes with the TomoEDGETM mode were 1.2% ± 0.8% (range: -0.6%, 1.8%) and 0.2% ± 0.5% (range: -0.6%, 0.9%), respectively (p

Method for Converting Cone-Beam CT Values into Hounsfield Units for Radiation Treatment Planning

Cone-beam CT (CBCT) images acquired during radiation treatment can be used to recalculate the dose distribution as well as to confirm the treatment location. However, it is difficult to obtain the electron densities (EDs) necessary for dose calculation from CBCT images because of the effects of scatter contamination during CBCT image acquisition. This paper presents a mathematical method for converting the pixel values of CBCT images (CBCT values) into Hounsfield units (HUs) of radiation treatment simulation CT (simCT) images for use in radiation treatment planning. CBCT values are converted into HUs by matching the histograms of the CBCT values with the histograms of the HUs for each slice via linear scaling of the CBCT values. For prostate cancer and head-and-neck cancer patients, the EDs obtained from converted CBCT values (mCBCT values) show good agreement with the EDs obtained from HUs, within approximately 3.0%, and the dose calculated on the basis of CBCT images shows good agreement with the dose calculated on the basis of the simCT images, within approximately 2.0%. Because the CBCT values are converted for each slice, this conversion method can account for variation in the CBCT values associated with differences in body size, body shape, and inner tissue structures, as well as in longitudinally displaced positions from the isocenter, unlike conventional methods that use electron density phantoms. This method improves on conventional CBCT-ED conversion and shows considerable potential for improving the accuracy of radiation treatment planning using CBCT images.

The Reproducibility of Patient Setup for Head and Neck Cancers Treated with Image-Guided and Intensity-Modulated Radiation Therapies Using Thermoplastic Immobilization Device

The reproducibility of patient setup is an important issue for head and neck cancers treated with intensity-modulated radiation therapy (IMRT). In this study, an image-guided radiation therapy (IGRT) system has been used to minimize the uncertainty of patient setup while standard thermoplastic masks were used to provide adequate immobilization for the head and neck. However, they do not provide sufficient immobilization of the shoulders, which is an important requirement in comprehensive nodal irradiation. Therefore, we investigated the setup and rotational shifts in head and neck cancer patients undergoing IMRT for which this immobilization device had been used together with an IGRT system. The setup and rotational shifts of patients were analyzed using the ExacTrac X-ray 6D IGRT system. The patients were classified as having head and neck tumors in the upper or lower regions. The upper neck nodes included lymph nodal level II while the lower neck nodes included lymph nodal levels III and IV. Clinical data from 227 treatment sessions of 12 head and neck cancer patients were analyzed. The random translational error in inter-and intra-fraction errors of the anterio-posterior (AP) direction might influence the rotational errors of pitch and roll in the upper region. At the same time, the random translational error in the inter-and intra-fraction errors of the AP direction might influence the rotational error of roll in the lower region. We believe that these random translational errors should be considered during treatment. We found variability in random translational errors for different regions in the anatomy of head and neck cancer patients due to rotational shifts. Depending on the location of the primary lesion or the selected nodal treatment targets, these relative positional variations should be considered when setup and rotational shifts are corrected with IGRT systems before treatment.

Harnessing macrophages in thermal and non-thermal ablative therapies for urologic cancers-Potential for immunotherapy

Prostate and bladder cancers are one of the cancers occurring worldwide.In addition to radical surgery,the past decade has also focused on targeted therapy of overexpressed cancer proteins that are lethal and critical for cancer cell survival.However,targeted therapy cannot adapt for changing of cancer molecular characteristics and,ultimately,a clone that bypasses the targeted therapy emerges.This can be overcome by immunotherapy.New studies on ablative therapy of cancers show presence of immunomodulatory effect in these modalities.Tumor ablation prime the immune system for further destruction of persistent primary tumor in addition to destruction of concurrent metastatic disease and also reduce recurrence.Ablative therapies can achieve a state of increased antigenicity.Its combination with a novel macrophage targeted therapy may enhance immune priming,trafficking,and/or effector phases;thereby improving clinical outcomes.Tumor associated macrophages or M2 phenotype are now known to mediate this immunosuppressive pro-tumorigenic effect.Alteration of macrophage differentiation may enhance tumor destruction of ablative therapy.This breakthrough in immunotherapy opens up arenas for further robust clinical trials on combinatorial therapies.In the present review,we aim to elucidate the major aspects of immune stimulatory minimal invasive approaches by combining with macrophage directed pathways.

Radiotherapy for Brain Metastases

Radiotherapy for Brain Metastases Brain metastases are common in patients with malignant tumors.According to the reports from autopsy,surgery and imaging investigations,the incidence of brain metastases is approximately 20%~40%[1].The main symptoms are headache,dementia and motor dysfunction.The most common primary sites are lung,breast,colorectal,melanoma and kidney.