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    Current Status of Postoperative Radiation for Non-Small-Cell Lung Cancer
    (W B Saunders Co-Elsevier Inc, 2010) Saynak, Mert; Higginson, Daniel S.; Morris, David E.; Marks, Lawrence B.
    Radiation therapy can increase local control and potentially improve survival in patients who have had resection for lung cancer. However, radiation therapy also has the potential to cause serious toxicity and should not be indiscriminately delivered. The PORT meta-analysis clearly illustrated the potential toxic effects of postoperative radiotherapy (PORT). Modern three-dimensional radiation treatment planning facilitates the design of treatment fields that more conformally treat the site(s) at risk, and this appears, based on limited data, to improve the therapeutic ratio of PORT. Moreover, systemic and local therapies are likely synergistic, and thus improvements in systemic staging and treatment may increase the ability of local therapies to improve overall survival. Therefore, a reassessment of the utility of postoperative radiation therapy using limited fields and modern techniques is warranted. Semin Radiat Oncol 20:192-200 (C) 2010 Elsevier Inc. All rights reserved.
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    The role of functional imaging in the diagnosis and management of late normal tissue injury
    (W B Saunders Co-Elsevier Inc, 2007) Evans, Elizabeth S.; Hahn, Carol A.; Kocak, Zafer; Zhou, Su-Min; Marks, Lawrence B.
    Normal tissue injury after radiation therapy (RT) can be defined based on either clinical symptoms or laboratory/radiologic tests. In the research setting, functional imaging (eg, single-photon emission computed tomography [SPECT], positron-emission tomography [PET], and magnetic resonance imaging [MRI]) is useful because it provides objective quantitative data such as metabolic activity, perfusion, and soft-tissue contrast within tissues and organs. For RT-induced lung, heart, and parotid gland injury, pre- and post-RT SPECT images can be compared with the dose- and volume-dependent nature of regional injury. In the brain, SPECT can detect changes in perfusion and blood flow post-RT, and PET can detect metabolic changes, particularly to regions of the brain that have received doses above 40 to 50 Gy. On MRI, changes in contrast-enhanced images, T-1 and T-2 relaxation times, and pulmonary vascular resistance at different intervals pre- and post-RT show its ability to detect and distinguish different phases of radiation pneumonitis. Similarly, conventional and diffusion-weighted MRI can be used to differentiate between normal tissue edema, necrosis, and tumor in the irradiated brain, and magnetic resonance spectroscopy can measure changes in compounds, indicative of membrane and neuron disruption. The use of functional imaging is a powerful tool for early detection of RT-induced normal tissue injury, which may be related to long-term clinically significant injury.
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    The Role of Imaging in the Study of Radiation-Induced Normal Tissue Injury
    (Springer-Verlag Berlin, 2008) Kocak, Zafer; Shankar, Lalitha; Sullivan, Daniel C.; Marks, Lawrence B.
    The recognition and assessment of normal tissue injury is an important aspect of radiation oncology practice and a critical endpoint in clinical studies. One of the major challenges in the study of radiation (RT)-induced normal tissue injury is determining the appropriate endpoint. Patients' symptoms have obvious clinical relevance; however, the scoring of symptoms is relatively subjective. Conversely, radiologic endpoints are potentially quantifiable and are available for objective I study. Furthermore, radiologic evidence of subclinical normal tissue injury is far more common than are clinical symptoms, providing a larger number of patients with identifiable injury for study. We review herein radiologically-detected normal tissue injury as it relates to the lung, heart, brain, and salivary glands. The concepts described are likely to be similar for other organs. We conclude that: (1) radiologically-defined normal tissue injury in human patients may be related to long-term clinically meaningful injury, but further study is needed to better quantify this association; (2) radiologically-defined normal tissue injury in human patients is manifest soon after (or even during) RT and hence is a potential tool to rapidly study potential mitigators of this injury in humans; and (3) additional work is needed to develop standards to quantitatively score radiologic injury. Thus, advances in anatomic and functional imaging afford unique opportunities to facilitate the study of radiation-associated normal tissue injury.
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    Solitary Fibrous Tumors of Chest: Another Look with the Oncologic Perspective
    (2017) Saynak, Mert; Veeramachaneni, Nirmal K.; Hubbs, Jessica L.; Okumuş, Dilruba; Marks, Lawrence B.
    Solitary fibrous tumors are mesenchymal lesions that arise at a variety of sites, most commonly the pleura. Most patients are asymptomatic at diagnosis, with lesions being detected incidentally. Nevertheless, some patients present due to symptoms from local tumor compression (eg. of the airways and pulmonary parenchyma). Furthermore, radiological methods are not always conclusive in making a diagnosis, and thus, pathological analysis is often required. In the past three decades, immunohistochemical techniques have provided a gold standard in solitary fibrous tumor diagnosis. The signature marker of solitary fibrous tumor is the presence of the NAB2-STAT6 fusion that can be reliably detected with a STAT6 antibody. While solitary fibrous tumors are most often benign, they can be malignant in 10-20% of the cases. Unfortunately, histological parameters are not always predictive of benign vs malignant solitary fibrous tumors. As solitary fibrous tumors are generally regarded as relatively chemoresistant tumors; treatment is often limited to localized treatment modalities. The optimal treatment of solitary fibrous tumors appears to be complete surgical resection for both primary and local recurrent disease. However, in cases of suboptimal resection, large disease burden, or advanced recurrence, a multidisciplinary approach may be preferable. Specifically, radiotherapy for inoperable local disease can provide palliation/shrinkage. Given their sometimes -unpredictable and often- protracted clinical course, long-term follow-up post-resection is recommended.
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    Stage III vs. stage IV lung cancer: Crossing a Great Divide
    (Elsevier Ireland Ltd, 2010) Marks, Lawrence B.; Saynak, Mert; Christodouleas, John P.
    [Abstract Not Available]