8-prenylnaringenin and tamoxifen inhibit the shedding of irradiated epithelial cells and increase the latency period of radiation-induced oral mucositis : cell culture and murine model.

Purpose: The major component in the pathogenesis of oral radiation-induced mucositis is progressive epithelial hypoplasia and eventual ulceration. Irradiation inhibits cell proliferation, while cell loss at the surface continues. We conceived to slow down this desquamation by increasing intercellular adhesion, regulated by the E-cadherin/catenin complex.

Direct effects of delta opioid receptor agonists on invasion-associated activities of HCT-8/E11 colon cancer cells.

Background: Opioids and opioid receptors are an integral part of the tumour microenvironment and hence may influence tumour progression. Studies on direct effects of opioids on invasion-associated cellular activities are equivocal. We wanted to clarify these differences.

Intensity-modulated radiotherapy for recurrent and second primary head and neck cancer in previously irradiated territory.

Purpose: To evaluate re-irradiation using IMRT for recurrent and second primary head and neck cancer in previously irradiated territory.

Materials And Methods: Between 1997 and 2008, 84 patients with recurrent and second primary head and neck cancer were treated with IMRT to a median dose of 69 Gy. Median time interval between initial radiotherapy and re-irradiation was 49.

The influence of small field sizes, penumbra, spot size and measurement depth on perturbation factors for microionization chambers.

The purpose of this study was the investigation of perturbation factors for microionization chambers in small field dosimetry and the influence of penumbra for different spot sizes. To this purpose, correlated sampling was implemented in the EGSnrc Monte Carlo (MC) user code cavity: CScavity. CScavity was first benchmarked against results in the literature for an NE2571 chamber.

The role of oncoplastic surgery in breast cancer.

The authors discuss the objectives of oncoplastic surgery in breast cancer management. Indications and advantages are summarised. Some surgical techniques are described.

Intensity-modulated radiotherapy for sinonasal tumors: Ghent University Hospital update.

Purpose: To report the long-term outcome of intensity-modulated radiotherapy (IMRT) for sinonasal tumors.

Methods And Materials: Between July 1998 and November 2006, 84 patients with sinonasal tumors were treated with IMRT to a median dose of 70 Gy in 35 fractions. Of the 84 patients, 73 had a primary tumor and 11 had local recurrence.

On the calibration process of film dosimetry: OLS inverse regression versus WLS inverse prediction.

The purpose of this study was both putting forward a statistically correct model for film calibration and the optimization of this process. A reliable calibration is needed in order to perform accurate reference dosimetry with radiographic (Gafchromic) film. Sometimes, an ordinary least squares simple linear (in the parameters) regression is applied to the dose-optical-density (OD) curve with the dose as a function of OD (inverse regression) or sometimes OD as a function of dose (inverse prediction).

Intensity-modulated radiotherapy for cervical lymph node metastases from unknown primary cancer.

Purpose: To compare the effectiveness of intensity-modulated radiotherapy (IMRT) and conventional (two-dimensional) radiotherapy in the treatment of cervical lymph node metastases from unknown primary cancer (UPC).

Methods And Materials: Between February 2003 and September 2006, 23 patients with UPC of squamous cell carcinoma were treated with IMRT. Extended putative mucosal and bilateral nodal sites were irradiated to a median dose of 66 Gy.

Monte Carlo modeling of the ModuLeaf miniature MLC for small field dosimetry and quality assurance of the clinical treatment planning system.

The purpose of this investigation was the verification of both the measured data and quality of the implementation of the add-on ModuLeaf miniature multileaf collimator (ML mMLC) into the clinical treatment planning system for conformal stereotactic radiosurgery treatment. To this end the treatment head with ML mMLC was modeled in the BEAMnrc Monte Carlo (MC) code. The 6 MV photon beams used in the setup were first benchmarked with a set of measurements.

Positron emission tomography-guided, focal-dose escalation using intensity-modulated radiotherapy for head and neck cancer.

Purpose: To assess the feasibility of intensity-modulated radiotherapy (IMRT) using positron emission tomography (PET)-guided dose escalation, and to determine the maximum tolerated dose in head and neck cancer.

Methods And Materials: A Phase I clinical trial was designed to escalate the dose limited to the [(18)-F]fluoro-2-deoxy-D-glucose positron emission tomography ((18)F-FDG-PET)-delineated subvolume within the gross tumor volume. Positron emission tomography scanning was performed in the treatment position.

Intensity-modulated radiation therapy for prostate cancer: late morbidity and results on biochemical control.

Purpose: To report on late morbidity and biochemical relapse-free survival (bRFS) after intensity-modulated radiation therapy (IMRT) for prostate cancer.

Methods: Between 1998 and 2005 133 patients were treated with IMRT for T(1-4) N0 M0 prostate cancer. The median follow-up time was 36 months.

99mTc-HYNIC Annexin-V imaging of tumors and its relationship to response to radiotherapy and/or chemotherapy.

Aim: The aim of this study was to report on the relationship between preradiotherapy and prechemotherapy 99mTc-HYNIC Annexin-V tumor uptake values, reflecting ongoing apoptosis, and outcome to radiotherapy and/or chemotherapy.

Methods: Twenty-three cancer patients underwent staging examinations and a 99mTc-HYNIC Annexin-V scintigraphy and subsequent radiotherapy and/or chemotherapy. Tumor-to-background ratios derived from tomographic 99mTc-HYNIC Annexin-V images were related to treatment outcome as assessed by RECIST criteria.

Systemic NO production during (septic) shock depends on parenchymal and not on hematopoietic cells: in vivo iNOS expression pattern in (septic) shock.

Septic shock is the leading cause of death in noncoronary intensive care units and the 10th leading cause of death overall. Several lines of evidence support an important role for the vasodilator NO in hypotension, a hallmark of septic shock. However, NO may also positively or negatively regulate inflammation, apoptosis, and oxidative stress.

Interobserver delineation variation using CT versus combined CT + MRI in intensity-modulated radiotherapy for prostate cancer.

Purpose: To quantify interobserver variation of prostate and seminal vesicle delineations using CT only versus CT + MRI in consensus reading with a radiologist.

Material And Methods: The prostate and seminal vesicles of 13 patients treated with intensity-modulated radiotherapy for prostatic adenocarcinoma were retrospectively delineated by three radiation oncologists on CT only and on CT + MRI in consensus reading with a radiologist. The volumes and margin positions were calculated and intermodality and interobserver variations were assessed for the clinical target volume (CTV), seminal vesicles, prostate and three prostatic subdivisions (apical, middle and basal third).

Postoperative intensity-modulated radiotherapy in sinonasal carcinoma: clinical results in 39 patients.

Background: Carcinoma of the paranasal sinuses is rare. Standard therapeutic modalities consist of surgery and radiotherapy (RT). Because of the often advanced stage and the vicinity of optic structures, RT-induced ocular toxicity is a feared side effect of conventional RT.

Automatic generation of a plan optimization volume for tangential field breast cancer radiation therapy.

Background And Purpose: Dose homogeneity is one of the objectives during computer planning of postoperative radiotherapy of the conserved breast. For three-dimensional (3-D) optimization of the dose distribution using serial CT scan images, suitable volumes have to be delineated. The purpose of this study was to develop a computer-generated delineation of a plan optimization volume (POV) and an irradiated volume (IV) and to automate their use in a fast dose homogeneity optimization engine.

Intensity-modulated radiotherapy as primary treatment for prostate cancer: acute toxicity in 114 patients.

Introduction: Dose escalation improves local control in prostate cancer. At Ghent University Hospital, intensity-modulated radiotherapy (IMRT) is used to increase the dose to the prostate and/or seminal vesicles. We report on acute toxicity in 114 patients who received IMRT for prostate cancer.

The incidence of inclusion of the sigmoid colon and small bowel in the planning target volume in radiotherapy for prostate cancer.

Background And Purpose: In radiotherapy for prostate cancer, the rectum is considered the dose-limiting organ. The incidence of overlap between the sigmoid colon and/or small bowel and the planning target volume (PTV) as well as the dose to sigmoid colon and small bowel were investigated.

Patients And Methods: The CT data of 75 prostate cancer patients were analyzed.

Pain control by ionizing radiation of bone metastasis.

Pain treatment due to cancer is a large fraction of the care in a radiotherapy department. While radiation treatment is very effective in reducing pain, the pathophysiology of bone metastases remains very complex. Reducing the number of tumour cells by radiation will reduce the pressure in bone marrow, but the very rapid response to radiation treatment seen in some patients is probably related to the presence of highly radiosensitive inflammatory cells.

Direct segment aperture and weight optimization for intensity-modulated radiotherapy of prostate cancer.

Background And Purpose: To describe the implementation and to evaluate the results of direct segment aperture optimization using the segment outline and weight adapting tool (SOWAT) in intensity-modulated radiotherapy (IMRT) for prostate cancer.

Patients And Methods: 14 consecutive, unselected patients with localized prostate cancer were entered in a planning study comparing IMRT without and with the use of SOWAT. The clinical target volume (CTV) consisted of the prostate and seminal vesicles in all cases.

G-protein alpha(olf) subunit promotes cellular invasion, survival, and neuroendocrine differentiation in digestive and urogenital epithelial cells.

The heterotrimeric G-protein subunits Galpha and Gbetagamma are involved in cellular transformation and tumor development. Here, we report the expression of Galpha(olf) in human digestive and urogenital epithelial cells using RT-PCR and Western blot. When the constitutively activated form of Galpha(olf)Q214L (AGalpha(olf)) was stably transfected in canine kidney MDCKts.