Publications by authors named "Kie Kian Ang"

Devices that combine magnetic resonance imaging with linear accelerators (MRL) represent a novel tool for MR-guided radiotherapy. However, whether magnetic fields (MFs) generated by these devices affect the radiosensitivity of tumors is unknown. We investigated the influence of a 1.

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Interaction between the epidermal growth factor receptor (EGFR) and the insulin-like growth factor receptor (IGF-1R) has been well established in many cancer types. We investigated the effects of cetuximab (EGFR antibody) and IMC-A12 (IGF-1R antibody) on the response of head and neck squamous cell carcinoma (HNSCC) to radiation therapy (RT). The effects of cetuximab and IMC-A12 on cell viability and radiosensitivity were determined by clonogenic cell survival assay.

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Purpose: We investigated whether expression of epidermal growth factor receptor (EGFR) was associated with survival and disease control in this secondary analysis of a phase II trial of cetuximab+chemoradiation for stage III non-small cell lung cancer.

Methods: Patients received cetuximab weekly before and during radiation (63 Gy/35 fractions/7 weeks) with weekly carboplatin + paclitaxel. We analyzed EGFR expression by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) in pretreatment biopsy specimens and compared findings with overall and progression-free survival (OS, PFS) and time to progression (TTP).

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Despite progress in the therapeutic management of patients with squamous cell carcinoma of the head and neck (SCCHN), the mortality rate of patients presenting with advanced disease remains high. One approach to improve treatment efficacy is to add novel molecular targeted agents to the classical treatment regimens. Monoclonal antibodies targeting the epidermal growth factor receptor (EGFR) have shown clinical benefits in palliative and curative settings.

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These NCCN Guidelines Insights focus on nutrition and supportive care for patients with head and neck cancers. This topic was a recent addition to the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Head and Neck Cancers. The NCCN Guidelines Insights focus on major updates to the NCCN Guidelines and discuss the new updates in greater detail.

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Radiation therapy for head and neck malignancies can have side effects that impede quality of life. Theoretically, proton therapy can reduce treatment-related morbidity by minimizing the dose to critical normal tissues. We evaluated the feasibility of spot-scanning proton therapy for head and neck malignancies and compared dosimetry between those plans and intensity-modulated radiation therapy (IMRT) plans.

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Background: Human papillomavirus (HPV) is a causative factor in squamous cell carcinomas of the anus, penis, vagina, vulva, and head and neck, and adenocarcinoma of the cervix. We examined the demographics, clinical characteristics, and timing of multiple potentially HPV-related cancers in individual patients.

Methods: One hundred forty-three patients were identified with 300 potentially HPV-related cancers.

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Background And Purpose: Improved radiation delivery and planning has allowed, in some instances, for the retreatment of thoracic tumors. We investigated the dose limits of the aorta wherein grade 5 aortic toxicity was observed after reirradiation of lung tumors.

Material And Methods: In a retrospective analysis, 35 patients were identified, between 1993 and 2008, who received two rounds of external beam irradiation that included the aorta in the radiation fields of both the initial and retreatment plans.

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Introduction: The radiation doses used to treat unresectable lung cancer are often limited by the proximity of normal tissues. Overexpression of c-Met, a receptor tyrosine kinase, occurs in about half of non-small-cell lung cancers (NSCLCs) and has been associated with resistance to radiation therapy and poor patient survival. We hypothesized that inhibiting c-Met would increase the sensitivity of NSCLC cells to radiation, enhancing the therapeutic ratio, which may potentially translate into improved local control.

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There has been a gradual change in the demographics of head and neck carcinoma. Although relatively uncommon, the incidence of oropharyngeal carcinoma has been increasing despite declining tobacco consumption and contrary to a diminishing incidence of cancers at other head and neck sites. It is now clear that the incidence of human papillomavirus (HPV)-associated oropharyngeal cancers is rising, likely as a consequence of changing life styles and sexual behaviors.

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Background: The aim of this study was to review institutional outcomes for anaplastic thyroid cancer treated with conformal 3-dimensional radiotherapy (3DRT) or intensity-modulated radiotherapy (IMRT).

Methods: In all, 53 consecutive patients were analyzed. Thirty-one (58%) patients were irradiated with curative intent.

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Background: To evaluate quality-adjusted survival (QAS) of patients with locally advanced squamous cell carcinoma of the head and neck treated with 4 different radiation fractionation schedules.

Methods: QAS was calculated using the quality-adjusted time without toxicity or relapse (Q-TWiST) methodology. Utilities (patient preferences for certain health states) were obtained by threshold analysis.

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Oral mucositis (OM) has emerged as a common cause of dose delays and interruptions of cancer therapies such as multicycle chemotherapy, myeloablative chemotherapy, and radiotherapy with or without concurrent chemotherapy of head and neck cancer. Research into both preventive and management strategies has lagged behind research into the common cancer treatment-related morbidities of nausea, vomiting, and cytopenias. This disparity is related to the complex risk assessment of multifactorial patient and treatment factors and different techniques of rating mucositis.

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Background: The purpose of this study is to catalog modern-era postoperative radiotherapy (external beam radiotherapy [EBRT]) outcomes for advanced medullary thyroid cancer.

Methods: Thirty-four consecutive patients with stage IVa-c disease were evaluated. Ten patients had recurrent disease, 16 had mediastinal involvement, and 10 had distant metastasis.

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Background: Our objectives were to determine the incidence of acute and late toxicities and to estimate the 2-year overall survival for patients treated with reirradiation and chemotherapy for unresectable squamous cell carcinoma of the head and neck (SCCHN).

Methods: Patients with recurrent squamous cell carcinoma or a second primary arising in a previously irradiated field were eligible. Four weekly cycles of 5-fluorouracil 300 mg/m2 IV bolus and hydroxyurea 1.

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Purpose: To examine experimental strategies for prevention of radiation-induced late spinal cord damage.

Material And Methods: The effects of treatment with high, proliferation-stimulating doses of platelet-derived growth factor (PDGF) administered at various times after radiotherapy of rat spinal cord, and aiming at increased tissue regeneration, were studied in an established model. Animals were followed and monitored for expression of radiation myelopathy (RM), which was confirmed by histopathologic diagnosis.

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Background: Survival has decreased among patients with laryngeal cancer during the past 2 decades in the United States. During this same period, there has been an increase in the nonsurgical treatment of laryngeal cancer.

Objective: The objectives of this study were to identify trends in the demographics, management, and outcome of laryngeal cancer in the United States and to analyze factors contributing to the decreased survival.

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Background: The aim was to evaluate the relationship between nutrition support (NS) on host toxicity and cancer outcome in patients with locally advanced head and neck squamous cell carcinoma (HNSCC) undergoing definitive radiotherapy (XRT).

Methods: We performed a secondary analysis of Radiation Therapy Oncology Group (RTOG) 90-03, a prospective randomized trial evaluating four definitive XRT fractionation schedules in patients with locally advanced HNSCC, which prospectively collected data on NS delivered before treatment (BNS), during treatment (TNS), and after definitive XRT. NS data and pretreatment characteristics of the 1073 evaluable patients were analyzed against therapy toxicity and outcome.

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Background: In 2004, level I evidence was established for the postoperative adjuvant treatment of patients with selected high-risk locally advanced head and neck cancers, with the publication of the results of two trials conducted in Europe (European Organization Research and Treatment of Cancer; EORTC) and the United States (Radiation Therapy Oncology Group; RTOG). Adjuvant chemotherapy-enhanced radiation therapy (CERT) was shown to be more efficacious than postoperative radiotherapy for these tumors in terms of locoregional control and disease-free survival. However, additional studies were needed to identify precisely which patients were most suitable for such intense treatment.

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Advances in radiation therapy over the past decade have resulted from increased accuracy of imaging and highly conformal three dimensional treatment planning and delivery of radiation therapy. Three-dimensional conformal radiation therapy (3D CRT) with higher doses than previously considered tolerable is now standard for many types of cancer. Intensity modulated radiation therapy (IMRT) with x-rays, proton beam treatments and intensity modulated proton therapy (IMPT) are major areas of research.

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