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CyberKnife® (Accuray Incorporated, Sunnyvale, CA) Frameless Image-Guided Radiosurgery [ 1 , 2 ] with the Synchrony® Motion Tracking Module (Accuray Incorporated) [ 3 , 4 ] is now available for the treatment of thoracic malignancies. Gold fiducial markers are required for the treatment planning and tracking of the tumor during each treatment. Fiducials have traditionally been placed percutaneously under CT-guidance. This chapter describes our center’s experience placing fiducials using flexible bronchoscopy with a transbronchial aspiration needle (TBNA).

The Synchrony® (Accuray Incorporated, Sunnyvale, CA) Respiratory Tracking System allows the CyberKnife®(Accuray Incorporated, Sunnyvale, CA) to deliver precisely high-dose radiation to targets that move with respiration. Tracking of moving tumors currently requires the use of implanted radiographic markers (or fiducials) as reference points [ 1 , 7 ]. Several reports describe the placement of fiducials through surgical or percutaneous methods under image guidance (ultrasonography or computed tomography) in the prostate, spine, and lungs [ 2 , 3 , 6 – 8 ]. Fiducial implantation surgery can be invasive, and the percutaneous approach carries risks and limitations, especially when the lesions are in a deep location such as the posterior mediastinum or the abdomen. Innovations in the fiducial implantation procedure may improve its accuracy and reduce its risks, ultimately enhancing comfort for the patient. We recently described a new approach to placing fiducials in these deep structures using endoscopic ultrasound (EUS) [ 9 ].

Lung cancer is a significant cause of morbidity and mortality in the United States, with an estimated 173,000 new lung cancer cases and 156,300 deaths due to lung cancer in 2003 [ 1 ]. Eighty-five percent of these patients are diagnosed with non-small cell lung cancer (NSCLC), of which 15–20% will have early stage disease [ 2 ]. Treatment options for early stage NSCLC depend on patient factors, such as pulmonary reserve, to determine if a patient is a surgical candidate or not. Typically, standard “cut-off” medical guidelines for surgical resection of NSCLC include the following: baseline forced expiratory volume in 1 s (FEV_1) < 40% of predicted, post-operative predicted FEV_1 < 30%, severely reduced diffusion capacity, baseline hypoxemia and/or hypercapnia, and exercise oxygen consumption < 50% predicted. For the relatively healthy patient, the traditional treatment of choice for Stage I (T1–2, N0, M0) NSCLC usually consists of radical surgery (lobectomy, pneumonectomy) resulting in an approximate 60% to 80% 5-year overall survival [ 3 ]–[ 5 ].

In the performance of stereotactic body radiotherapy (SBRT), one must take into consideration not only the biology of the cancer being treated, but the physics and dosimetry behind delivery of the radiation dose. In a sense, investigation of the clinical application has begun before the basic research has been performed. Investigation of the biology of large-fraction radiotherapy has only started, but due to its potential for significant toxicity, extremely stringent conditions must be applied after due consideration. Here we examine some of the issues.

Lung cancer is the leading cause of cancer mortality in men and women. More than 170,000 Americans receive a diagnosis of lung cancer annually and the majority of them die of the disease [ 1 ]. There is considerable interest in improving treatment for lung cancer given its high impact on society. More than 80% of patients with lung cancer have non-small cell carcinoma (NSCLC). Surgery is the mainstay of treatment for patients with early stage NSCLC and results in cure of about 60–80% of patients with stage I (T1-2N0) disease [ 2 ]–[ 5 ].

Curative surgery is not an option for many patients with clinical stage I non-small-cell lung carcinoma (NSCLC) because of associated comorbidities. Stereotactic radiosurgery with the CyberKnife® (Accuray Incorporated, Sunnyvale, CA) tumor tracking system may be an option for many of these medically inoperable patients. Here we provide a concise overview of the standard treatment options for stage I lung cancer and a practical summary of the Georgetown University Hospital stereotactic radiosurgery treatment protocol. We review preliminary outcomes for single small peripheral lung tumors uniformly treated with the CyberKnife using the Synchrony® (Accuray Incorporated, Sunnyvale, CA) motion tracking module.

Stereotactic body radiosurgery (SBRS) of lung tumors with the CyberKnife® (Accuray Incorporated, Sunnyvale, CA) achieves excellent rates of local disease control with limited toxicity to surrounding tissues. We retrospectively reviewed treatments and outcomes for 90 patients with 109 lung lesions treated at the CyberKnife Center of Miami between March 2004 and September 2006. This monotherapy review included 49 patients with 53 primary lung cancers, 27 patients with 42 pulmonary metastases, 6 patients with external beam failure and 8 patients treated by SBRS as a boost following or before conventionally fractionated radiotherapy (3DCRT or IMRT). In the primary tumor category, 43 patients remain alive. Thirty-two have been followed 1 to 25 months (median = 11.5 months). Fortynine percent (21/43) of them have had a complete radiographic response and have been followed for a median of 18.5 months. Another 8 have evidence of at least a partial radiographic response. There have been 5 failures (5/43) within the PTV, for a local recurrence rate of 11%. Of the total 109 treated lesions, 97/109 (89%) showed radiographic evidence of at least a partial response to treatment. Six of the failures were in lesions < 20 cc; 4 were in lesions 21–100 cc and 2 were in lesions > 100 cc. All of the patients tolerated SBRS well with fatigue as the main toxicity. Two patients required hospitalization for Grade III radiation pneumonitis. We conclude that the delivery of precisely targeted, high dose, hypofractionated irradiation to lung tumors with the CyberKnife is well tolerated and has outcomes that are comparable with published results for other methods of SBRS.

Lung cancer is the most common cause of cancer death [ 1 ]. While advanced disease portends a very poor prognosis, the subset of patients who present with localized disease are potentially curable. Anatomic lobectomy is the current standard of care for early stage lung cancer [ 2 ]. Sub-lobar resection is generally reserved for patients with inadequate pulmonary reserve. For patients with small tumors (2 cm or less) new data suggests that sub-lobar resection may be adequate [ 3 , 4 ]. It has also become apparent that patients with very marginal pulmonary reserve may safely tolerate lung resection or even have improved pulmonary function afterwards [ 5 , 6 ].

When pondering the choice of therapy for a cancer, clinicians must weigh the risks and benefits of each modality individually for each patient, taking into account age, coexisting medical problems, general fitness, therapeutic toxicity, and therapeutic efficacy. This chapter will focus on lung cancer and other tumors in an area of the chest fraught with potential complications: the mediastinum and hilum. We will briefly review the literature on toxicity and efficacy of radiotherapy to the central chest, and then present some of our early experience with stereotactic body radiotherapy (SBRT) to this difficult area.

The first published experience with stereotactic body radiotherapy was reported on the treatment of liver malignancies at the Karolinska Institute in Stockholm, Sweden in the early 1990s. Since then, two different treatment schedules have evolved: hypofractionated radiation therapy, mostly using 3 fractions, and the radiosurgical approach, using single-dose therapy. As opposed to the stereotactic treatment of liver tumors, little has been published about stereotactic treatments of pancreatic tumors. The following chapter reviews the history of stereotactic radiation therapy of liver and pancreas tumors including recent updates of ongoing clinical trials.