Predictors of Survival for Patients with Non-small Cell Lung Cancer and Synchronous Brain Metastases with FDG-PET/CT Staging

Purpose: The clinical course of patients diagnosed with non-small cell lung cancer (NSCLC) with brain metastases (BM) at presentation is variable. Here we seek to identify predictors of survival in patients staged with FDG-PET/CT. American Association of Physicists in Medicine (AAPM) 52nd Annual Meeting July 18-22, Philadelphia, P

Decrease of Morbidity and Cost of Care with Prophylactic Cranial Irradiation for Non-small Cell Lung Cancer

Purpose: While several studies analyze the incidence of brain metastases in patients with non-small cell lung cancer (NSCLC) treated with prophylactic cranial irradiation (PCI), there is little data available on how this treatment can affect medical cost and morbidity. Our goal was to analyze those issues patients encounter secondary to brain metastases, often in the final months of their lives, and to support the hypothesis of economic benefit and cost effectiveness resulting from the use of PCI in this population. American Society for Therapeutic Radiation Oncology (ASTRO) 52nd Annual Meeting October 31 - November 4, San Diego, C

Combination of Vorinostat with Whole-brain Radiotherapy in the Treatment of Brain Metastases

Background: A third of patients with solid malignancies develop brain metastases. Expected overall survival is 4-7 months depending on age, performance status, and extracranial disease. Standard treatment is controversial; however, the majority of patients receive wholebrain radiation therapy at some point. Vorinostat (suberoylanilide hydroxamic acid, SAHA), an FDA-approved HDAC inhibitor, has been demonstrated to radiosensitize tumor cells in vitro, as assessed by both radiation-induced DNA damage and clonogenic cell survival (Munshi et al. Molecular Cancer Therapeutics 5, 1967-1974, 2006). We have shown that vorinostat downregulates key genes involved in double-strand DNA repair (Rad50, Rad51, XRCC2, XRCC3, XRCC6), as assessed by quantitative PCR. This suggests that the drug’s mechanism of radiosensitization is epigenetic coordinated inhibition of the DNA repair process. We hypothesize that the combination of vorinostat with whole-brain radiation therapy will be both safe and efficacious. American Society of Clinical Oncology (ASCO) 46th Annual Meeting June 4-8, Chicago, IL

Reirradiation for Recurrent Meningioma

Purpose/Objective(s): Management options for meningioma include observation, surgical resection, and radiation therapy (RT). In cases of progressive or recurrent disease after RT, similar options exist. The control rate following a second course of RT is unknown. American Society for Therapeutic Radiation Oncology (ASTRO) 52nd Annual Meeting October 31 - November 4, San Diego, C

Dosimetric Evaluation of Tumor Tracking in 4D Radiotherapy

Purpose: In some patients the tumors in lung, pancreas, liver, breast, and other organs move significantly during cardiac and breathing cycles. In this study we have investigated the dosimetric benefits of real-time tumor tracking for patients who were diagnosed with lung cancer. American Society for Therapeutic Radiation Oncology (ASTRO) 52nd Annual Meeting October 31 - November 4, San Diego, C

Pathologic Correlation of PET-CT Based Auto Contouring for Radiation Planning in Lung Cancer

Purpose/Objective(s): Radiation therapy in lung cancer relies on CT and functional imaging (FDG-PET) to delineate tumor volumes. Semi-automatic contouring tools have been developed for PET to improve on the inter-observer bias of manual contouring and intrinsic differences in imaging equipment. A common method involves using a threshold at a given percentage of the max activity, which may be less accurate with smaller tumors and tumors with low source to background ratio. To overcome this deficiency, a gradient algorithm, which detects changes in image counts at the border of the tumor, has been developed. Few studies have correlated these methods to pathological specimens. American Society for Therapeutic Radiation Oncology (ASTRO) 52nd Annual Meeting October 31 - November 4, San Diego, C

Substantial Dose-response Relationship with Clinical Outcome for Lung Stereotactic Body Radiotherapy (SBRT) Delivered via Online Image Guidance

Purpose: To examine potential tumor dose-response relationships with various non-small cell lung cancer (NSCLC) SBRT fractionation regimens delivered with online CT-based image guidance. American Society for Therapeutic Radiation Oncology (ASTRO) 52nd Annual Meeting October 31 - November 4, San Diego, C

Dosimetric Advantages of Active Tracking and Dynamic Dose Delivery

Purpose: To investigate dosimetric effect of tumor tracking. To evaluate changes of treatment volumes when tracking is applied. American Association of Physicists in Medicine (AAPM) 52nd Annual Meeting July 18-22, Philadelphia, PA

Performance Study of Novel Accelerationenhanced Filters in the Prediction of Normal and Irregular Respiration Motion

Purpose: To study the performance of the novel acceleration-enhanced (AE) filters in the prediction of normal and irregular respiration motion and compare them with those of traditional adaptive normalized least mean squares (nLMS) and adaptive neuron network (ANN) filters. This facilitates the real-time tumor tracking and dynamic delivery of radiation dose to the tumor. American Association of Physicists in Medicine (AAPM) 52nd Annual Meeting July 18-22, Philadelphia, P