Reduction in stray radiation dose using a body-shielding device during external radiation therapy.

With the purpose of reducing stray radiation dose (SRD) in out-of-field region (OFR) during radiotherapy with 6 MV intensity-modulated radiation therapy (IMRT), a body-shielding device (BSD) was prepared according to the measurements obtained in experimental testing. In experimental testing, optimal shielding conditions, such as 1 mm lead, 2 mm lead, and 1 mm lead plus 10 mm bolus, were investigated along the medial axis of a phantom using thermoluminescent dosimeters (TLDs). The SRDs at distances from field edge were then measured and analyzed for a clinical IMRT treatment plan for nasopharyngeal carcinoma before and after shielding using the BSD.

Analysis of setup error based on CTVision for nasopharyngeal carcinoma during IGRT.

The aim of the present study was to investigate the role of CTVision in interfractional setup errors during intensity-modulated radiation therapy (IMRT) in 12 nasopharyngeal carcinoma (NPC) patients. The trend of setup errors as a function of time during a fractionated radiotherapy course was investigated, and the influence of reconstructive thickness on image reconstruction for setup errors was analyzed. The appropriate planning target volume (PTV) margin and planning risk volume (PRV) margin were defined to provide a reference for the design of IMRT for NPC.

Optimal beam arrangement for pulmonary ventilation image-guided intensity-modulated radiotherapy for lung cancer.

Background: The principal aim of this study was to evaluate the feasibility of incorporating four-dimensional (4D)-computed tomography (CT)-based functional information into treatment planning and to evaluate the potential benefits of individualized beam setups to better protect lung functionality in patients with non-small cell lung cancer (NSCLC).

Methods: Peak-exhale and peak-inhale CT scans were carried out in 16 patients with NSCLC treated with intensity-modulated radiotherapy (IMRT). 4D-CT-based ventilation information was generated from the two sets of CT images using deformable image registration.

Volume and dosimetric variations during two-phase adaptive intensity-modulated radiotherapy for locally advanced nasopharyngeal carcinoma.

The aims of this study were to evaluate the volume and dosimetric variations during IMRT for locally advanced NPC and to identify the benefits of a two-phase adaptive IMRT method. Twenty patients with locally advanced NPC having received IMRT treatment were included. Each patient had both an initial planning CT (CT-1) and a repeated CT scan (CT-2) after treatment at a dose of 40 Gy.

4D-CT reconstruction based on pulmonary average CT values.

To date, commercial 4D-CT systems typically depend on an external respiratory monitoring device. Immobilizing patients in a thermoplastic mask while receiving radiotherapy may result in a failure of 4D-CT reconstruction. The aim of this study is to investigate the feasibility of 4D-CT reconstruction based on a method using pulmonary average CT values (ACV) without an external respiratory monitoring device.

Up-regulation of PIK3CA promotes metastasis in gastric carcinoma.

Aim: To explore expressions of PIK3CA in the progression of gastric cancer from primary to metastasis and its effects on activation of phosphatidylinositol 3-kinase (PI3K)/Akt pathway.

Methods: mRNA and protein levels of PIK3CA were assessed, respectively, by real-time quantitative polymerase chain reaction and immunohistochemistry in specimens of normal gastric mucosa, primary foci and lymph node and distant metastasis of gastric cancer. Akt and phosphorylated Akt protein were also examined by Western blotting in these tissues, in order to analyze the effect of PIK3CA expression level changes on the activation of PI3K/Akt signaling pathway.

Lack of association between the GRP78 polymorphisms in the promoter and 3' UTR and susceptibility to chronic HBV infection in a Chinese Han population.

Background: Hepatitis B virus (HBV) infection causes large amount of unfolding or false-folding protein accumulation in the endoplasmic reticulum (ER), which in turn induces the expression of glucose-regulated protein 78 (GRP78). The aim in the present study was to analyse the potential association between GRP78 single-nucleotide polymorphisms (SNPs) and the risk of HBV infection.

Methods: The associations between seven common GRP78 polymorphisms in the promoter (rs391957, rs17840762, rs17840761, rs11355458) and in the 3' untranslated region (UTR) (rs16927997, rs1140763, rs12009) and possible risk of chronic HBV infection were assessed in a case-control study.

Chemotherapy with laparoscope-assisted continuous circulatory hyperthermic intraperitoneal perfusion for malignant ascites.

Aim: To investigate the procedure, feasibility and effects of laparoscope-assisted continuous circulatory hyperthermic intraperitoneal perfusion chemotherapy (CHIPC) in treatment of malignant ascites induced by peritoneal carcinomatosis from gastric cancers.

Methods: From August 2006 to March 2008, the laparoscopic approach was used to perform CHIPC on 16 patients with malignant ascites induced by gastric cancer or postoperative intraperitoneal seeding. Each patient underwent CHIPC three times after laparoscope-assisted perfusion catheters placing.

Resection of a giant hepatocellular carcinoma weighing over ten kilograms.

The authors report a giant hepatocellular carcinoma (HCC) with a diameter over 30 cm and weight over 10 kg that was resected completely. A 62-year-old man was admitted because of continuous abdominal uplift. A computed tomography scan demonstrated that the entire abdomen was filled with a giant tumor containing both cystic and solid components with a size of 29 cm x 22 cm.

[Comparison of the irradiation doses for IMRT and conventional radiotherapy in nasopharyngeal carcinoma patients].

Objective: To compare the dose difference in irradiation dose between nasopharyngeal cancer patients receiving conventional radiotherapy (CR) and intensity-modulated radiotherapy (IMRT).

Methods: The various IMRT and the CR plans for patients with nasopharyngeal carcinoma were created by a three-dimensional treatment planning system (3D-TPS). The dose-volume histograms (DVH) of normal tissues and the total number of irradiation monitor units (MU) were calculated by 3D-TPS.

[Radiofrequency thermal ablation combined with arterial embolization for primary liver cancer].

Objective: To explore the short-term effect of radiofrequency ablation (RFA) combined with arterial embolization in treating patients with primary liver cancer.

Methods: Thirty patients with primary liver cancer received the combined treatment and the pre- and post-operative alpha-fetoprotein (AFP) levels, imaging features, and liver function were investigated along with observation of the incidence of complications to evaluate the therapeutic effects.

Results: The post-operative AFP positivity and the tumor density were significantly reduced in these patients, and their one-year survival rate reached 96.