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Primary neoplasms of the spine encompass a broad spectrum of tumors, ranging in their tissue of origin, local behavior, and potential for metastasis. The diagnosis and treatment of these disorders is accordingly varied. As a category, non-myeloproliferative primary tumors of the spine are rare, accounting for approx 5% of all bone tumors, when one excludes hemangiomas (,). In frequency, therefore, they are much less common than metastatic and/or myeloproliferative neoplasms involving the spine, as well as non-neoplastic processes such as infection, metabolic disorders, and other pathologies. The diagnosis of primary tumors of the spine, therefore, must occur with careful consideration of other more common entities. In this chapter, we discuss the common benign and malignant tumors that afflict the spinal column, and describe the appropriate algorithm for evaluating and treating these conditions.

Radiation therapy is an important modality in the management of both primary and metastatic tumors involving the spine and spinal cord. The mesenchymal elements of the spinal column and its contents may give rise to a wide variety of primary tumors. Yet, primary neoplastic lesions of the spine are rare, accounting for roughly 5 to 10% of all skeletal tumors. Metastatic lesions of the spine are far more common (). True spinal cord neoplasms are relatively rare and typically intradural in location. Radiation therapy has evolved over the past decades to better meet these needs. Better pretreatment imaging studies, megavoltage linear accelerators, and computer-based three-dimentional (3D) treatment planning are all improving radiation dose distributions, thus, decreasing the likelihood of severe acute or late toxicity.

Radiation therapy (RT) in the pediatric population presents challenging dilemmas to the clinician. Some of the pediatric malignancies are treated according to multi-institutional multimodality trials that guide the indications and techniques within specific parameters. Because of the extremely low incidence of primary spinal malignancies, multi-institutional trials have not been implemented. Most experience has been gained through the retrospective single institution review of patient management and outcome. The application of RT as a therapeutic modality in the management of pediatric malignancies has to be carefully evaluated because the potential for long-term consequences in this population is significant. The indications for RT are constantly evolving and in a few instances are controversial.

In the spine, as elsewhere, conventional doses and treatment schedules in radiotherapy have been titrated to the clinical tolerance of normal tissues. Protracted treatment courses delivered over several weeks, “fractionated schedules,” are a radiobiological compromise employed to permit normal tissue repair between multiple small doses of radiation with the goal of reducing morbid late effects of treatment. Radiotherapy is widely used because this approach is often successful in dealing with microscopic disease or particularly radio-sensitive tumors, however, for bulky disease or radio-resistant tumors, sterilizing tumoricidal doses may never be reached owing to limitations imposed by nearby critical structures such as the spinal cord.

Over the last 30 yr, the treatment of primary and metastatic tumors of the cervical, thoracic, and lumbar spine has evolved dramatically. In the case of primary tumors of the spine, advances in neoadjuvant treatments and instrumentation techniques have offered patients with previously inoperable disease new options with reasonable chances of cure. When the overall morbidity of radical resection makes it a poor treatment option, radiation therapy can be combined with more conservative surgical procedures or can be used in lieu of surgery for palliation, or even cure in some instances. With new advances in radiotherapy techniques, greater doses of radiation (often tumorocidal doses) can be administered to the majority of tumor volume with fewer effects on the surrounding structures and, most particularly, minimal risk to the spinal cord. It is imperative for the clinician and surgeon to be familiar with these new techniques so that the care of their patients can be optimized, with the highest potential for long-term survival and reduced morbidity.

Each year approx 1.37 million new cases of cancer are diagnosed in the United States. It is estimated that approx 563,700 of these new cases will die from their disease (). Despite significant advances in the overall management of cancer in the past decades, the major cause of death in most cases remains metastatic disease and its complications. The three most common sites for metastasis are the lungs, liver, and skeletal system. The spine is the most common site for skeletal metastasis. Based on autopsy studies, approx 5 to 30% of patients with cancer will develop spinal metastasis, with 20% of these patients developing epidural compression (–).

The primary goal of biopsy is to obtain adequate tissue for histopathological diagnosis with minimal amount of trauma (). In patients with a known primary tumor, biopsy is often used to confirm metastatic disease or to obtain tissue for hormonal evaluation () Without a history of malignancy, the appropriately performed biopsy plays a crucial role in the diagnosis and subsequent management process. Conversely, a poorly planned biopsy can result in misdiagnosis, complications, and adversely limit potential treatment options.

The surgical decision-making process is an art form. No single strategy always works, and even the most inadequate of strategies will work occasionally. The decision-making process involves the assimilation of prior experience of others (e.g., by a learned assessment of the literature), and an in-depth knowledge and awareness of the application of biomechanical and anatomical factors and principles ().

Tumors of the vertebral column include both primary and metastatic lesions. These tumors can cause significant morbidity consisting of lesional pain and pain from deformity. Compression of the spinal cord and spinal nerve roots can also cause radicular pain as well as neurologial deterioration including sensory deficits, weakness, paralysis, and/or sexual/bowel/ bladder dysfunction. In cases of metastatic lesions, the spine is the most common region of osseous involvement (). Metastatic vertebral spine lesions can result in pathological fractures or have significant epidural tumor involvement, both of which can lead to neurological deterioration (). Mortality and morbidity can be significant in malignant tumors and overall treatment is best addressed by a multidisciplinary approach.

Metastatic spine tumors occur in 5 to 10% of all cancer patients (–). Cervical spine involvement is relatively uncommon, accounting for less than 10% of all spinal metastases (,,,). The most prevalent tumors are lung, breast, prostate, kidney, and thyroid (,,–). Most patients presenting with cervical spine tumors generally have extra-cervical and extra-spinal sites of disease at presentation (). Radiation therapy, surgery, or a combination, are the primary treatment modalities for cervical spine tumors. Treatment decisions are based primarily on the segmental level of cervical spine involvement, radio-sensitivity of the tumor, presence of mechanical instability, and prior treatment.