Radiation proctopathy in the treatment of prostate cancer.

Purpose: To compile and review data on radiation proctopathy in the treatment of prostate cancer with respect to epidemiology, clinical manifestations, pathogenesis, risk factors, and treatment.

Methods: Medical literature databases including PubMed and Medline were screened for pertinent reports, and critically analyzed for relevance in the scope of our purpose.

Results: Rectal toxicity as a complication of radiotherapy has received attention over the past decade, especially with the advent of dose-escalation in prostate cancer treatment.

Tolerance of endorectal balloon in 396 patients treated with intensity-modulated radiation therapy (IMRT) for prostate cancer.

Purpose: To report patient tolerance and acute anorectal toxicity of an endorectal balloon used for prostate immobilization during 35 daily fractions.

Materials And Methods: The records of 396 patients treated for prostate cancer from October 1997 to November 2001 were reviewed. Patients were treated with intensity modulated radiation therapy (IMRT).

Impact of setup uncertainty in the dosimetry of prostate and surrounding tissues in prostate cancer patients treated with Peacock/IMRT.

The purpose of this paper was to assess the effect of setup uncertainty on dosimetry of prostate, seminal vesicles, bladder, rectum, and colon in prostate cancer patients treated with Peacock intensity-modulated radiation therapy (IMRT). Ten patients underwent computed tomography (CT) scans using the "prostate box" for external, and an "endorectal balloon" for target immobilization devices, and treatment plans were generated (T1). A maximum of +/-5-mm setup error was chosen to model dosimetric effects.

Hypofractionated intensity-modulated radiotherapy for primary glioblastoma multiforme.

Purpose: A pilot study was designed to evaluate the safety and efficacy of a novel regimen of hypofractionated intensity-modulated radiotherapy (RT) in the adjuvant treatment of primary glioblastoma multiforme (GBM). The rationale of the study was to combine the potential radiobiologic advantage of hypofractionation to GBM with a highly conformal radiotherapeutic technique. The study was designed to measure the acute and chronic morbidity of patients treated with this regimen, response of GBM to the treatment, overall survival, and time to disease progression after therapy completion.

Initial experience using intensity-modulated radiotherapy for recurrent nasopharyngeal carcinoma.

Purpose: To report our initial experience on the feasibility, toxicity, and tumor control using intensity-modulated radiotherapy (IMRT) for retreatment of recurrent nasopharyngeal carcinoma (NPC).

Methods And Materials: A total of 49 patients with locoregional recurrent carcinoma in the nasopharynx were treated with IMRT between January 2001 and February 2002 at the Sun Yat-Sen University Cancer Center, Guangzhou, China. The average time to the nasopharyngeal recurrence was 30.

IMRT for prostate cancer: defining target volume based on correlated pathologic volume of disease.

Purpose: The intensity-modulated radiation therapy (IMRT) treatment planning system generates tightly constricted isodose lines. It is very important to define the margins that are acceptable in the treatment of prostate cancer to maximize the dose escalation and normal tissue avoidance advantages offered by IMRT. It is necessary to take into account subclinical disease and the potential for extracapsular spread.

Dosimetric predictors of xerostomia for head-and-neck cancer patients treated with the smart (simultaneous modulated accelerated radiation therapy) boost technique.

Purpose: To evaluate the predictors of xerostomia in the treatment of head-and-neck cancers treated with intensity-modulated radiation therapy (IMRT), using the simultaneous modulated accelerated radiation therapy (SMART) boost technique. Dosimetric parameters of the parotid glands are correlated to subjective salivary gland function.

Materials And Methods: Between January 1996 and June 2000, 30 patients with at least 6 months follow-up were evaluated for subjective xerostomia after being treated definitively for head-and-neck cancer with the SMART boost technique.

Using technology to decrease xerostomia for head and neck cancer patients treated with radiation therapy.

The treatment of head and neck cancer has evolved from conventional fields encompassing large volumes of normal tissue to focused treatment aimed at conforming the dose around the target while avoiding normal tissue. Intensity modulated radiation therapy has changed the way radiation oncologists think about head and neck cancer. Using the concepts of conformal treatment and avoidance, the therapeutic ratio can be improved and technology exploited to the patients' advantage.

The use of rectal balloon during the delivery of intensity modulated radiotherapy (IMRT) for prostate cancer: more than just a prostate gland immobilization device?

Purpose: The purpose of this study was to investigate the role of a rectal balloon for prostate immobilization and rectal toxicity reduction in patients receiving dose-escalated intensity-modulated radiotherapy for prostate cancer.

Patients And Methods: Patients with localized prostate cancer who were undergoing intensity-modulated radiotherapy were treated in a prone position, immobilized with a customized Vac-Lok bag (MED-TEC, Orange City, IA). A rectal balloon with 100 cc of air was used to immobilize the prostate.

Combining radiotherapy with gene therapy (from the bench to the bedside): a novel treatment strategy for prostate cancer.

Combined radiotherapy and gene therapy is a novel therapeutic approach for prostate cancer. There are various potential benefits in combining ionizing radiation with gene therapy to achieve enhanced antitumor effects: A) ionizing radiation improves transfection/ transduction efficiency, transgene integration, and possibly, the "bystander effect" of gene therapy; B) gene therapy, on the other hand, may interfere with repair of radiation-induced DNA damage and increase DNA susceptibility to radiation damage in cancer cells, and C) radiotherapy and gene therapy target at different parts of the cell cycle. Preclinical data have demonstrated the enhanced antitumor effects of this combined approach in local tumor control, prolongation of survival, as well as systemic control.

Post-nerve-sparing prostatectomy, dose-escalated intensity-modulated radiotherapy: effect on erectile function.

Purpose: The advent of widespread prostate-specific antigen screening has resulted in more younger, potent men being diagnosed with early-stage, organ-confined prostate cancer amenable to definitive surgery. Nerve-sparing prostatectomy is a relatively new surgical advance in the treatment of prostate cancer. Very few data exist on the effect of postoperative radiotherapy (RT) on erectile function after nerve-sparing prostatectomy.

Intensity-modulated radiation therapy (IMRT) for meningioma.

Purpose: To assess the safety and efficacy of intensity-modulated radiation therapy (IMRT) in the treatment of intracranial meningioma.

Methods And Materials: Forty patients with intracranial meningioma (excluding optic nerve sheath meningiomas) were treated using IMRT with the NOMOS Peacock system between 1994 and 1999. Twenty-five patients received IMRT after surgery either as adjuvant therapy for incomplete resection or for recurrence, and 15 patients received definitive IMRT after presumptive diagnosis based on imaging.

Intensity modulated radiotherapy (IMRT) decreases treatment-related morbidity and potentially enhances tumor control.

Intensity modulated radiation therapy (IMRT), a new form of three-dimensional conformal radiation therapy (3DCRT), optimizes the concept of computer-controlled radiation deposition in tumor (target) while sparing adjacent normal structures. A retrospective review was done on the initial 185 patients with tumors in different sites including prostate cancer, head and neck cancer, pediatric tumors, adult brain tumors, and previously irradiated recurrent tumors treated with IMRT. Preliminary findings indicate that IMRT is a new clinically feasible tool in radiation oncology.

Clinical experience with intensity-modulated radiation therapy (IMRT) for prostate cancer with the use of rectal balloon for prostate immobilization.

The implementation of intensity-modulated radiation therapy (IMRT) is the result of advances in imaging, radiotherapy planning technologies, and computer-controlled linear accelerators. IMRT allows both conformal treatment of tumors and conformal avoidance of the surrounding normal structures. The first patient treated with Peacock IMRT at Baylor College of Medicine took place in March 1994.

Intensity-modulated radiation therapy for pediatric medulloblastoma: early report on the reduction of ototoxicity.

Purpose: The combination of cisplatin chemotherapy and radiation therapy for the treatment of medulloblastoma has been shown to cause significant ototoxicity, impairing a child's cognitive function and quality of life. Our purpose is to determine whether the new conformal technique of intensity-modulated radiation therapy (IMRT) can achieve lower rates of hearing loss by decreasing the radiation dose delivered to the cochlea and eighth cranial nerve (auditory apparatus).

Patients And Methods: Twenty-six pediatric patients treated for medulloblastoma were retrospectively divided into two groups that received either conventional radiotherapy (Conventional-RT Group) or IMRT (IMRT Group).