Neurologic oncology
Neurologic oncology, also referred to as neuro-oncology, is a specialized field focused on the study and treatment of cancers affecting the brain and the central and peripheral nervous systems. Neuro-oncologists, the physicians in this specialty, combine knowledge from various disciplines, including neurology, neurosurgery, and oncology, to diagnose and manage tumors effectively. This field has evolved significantly since the 1980s, leveraging advancements in understanding cancer biology and treatment methodologies.
Neuro-oncologists utilize modern imaging techniques such as PET and fMRI for accurate tumor diagnosis, followed by treatment options that may include surgery, chemotherapy, and radiation therapy. There are specific types of chemotherapy agents and radiotherapy techniques, including brachytherapy and radiosurgery, tailored to individual patient needs. Training for neuro-oncologists typically includes extensive education in related medical fields, followed by specialized fellowship training in neurologic oncology.
Collaboration among a multidisciplinary team, including various medical specialists and supportive care providers, is crucial in the treatment process. This approach ensures comprehensive care addressing both the oncologic and neurological aspects of patient health, catering to the unique challenges posed by central nervous system cancers.
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Neurologic oncology
ALSO KNOWN AS: Neuro-oncology
DEFINITION: Neurologic oncology is a specialty practice involving studying and treating cancers of the brain and the peripheral and central nervous systems. Physicians who practice in this field are known as neuro-oncologists. It is a branch of medicine that studies tumors to understand their evolution, diagnosis, treatment, and prevention. The discipline of neurologic oncology has developed steadily since the 1980s as advances in the understanding of epidemiology, cellular and molecular biology, genetics, immunology, and radiobiology have come together to increase knowledge of the process of oncogenesis.
Cancers treated:Brain and central nervous system, spinal, and peripheral nervous system cancers
Training and certification: The practice of neurologic oncology requires training and experience in neurology or neurosurgery to properly diagnose and assess patients based on expert knowledge of nervous system function and oncology as it pertains to central nervous system (CNS) involvement and generic oncologic management principles for competence in the use of chemotherapeutic agents and related measures. Although no official or regulated prerequisites have been established for neuro-oncologists, all neurologic oncology physicians have graduate medical degrees. Most physicians practicing neuro-oncology have backgrounds in neurology, neurosurgery, radiology/radiation oncology, or internal medicine/medical oncology. The specialty of neurology generally requires the completion of a one-year internship and a three-year residency program. The specialty of neurosurgery requires the completion of a five- to seven-year residency program. Radiologists complete a four- to six-year residency program. Physicians trained in internal medicine complete a three-year residency program. After completing a residency program, the physician assumes a fellowship in neurologic oncology for two to three years, depending on whether the individual plans to engage in research and academic activities or treat patients with brain, spinal cord, or CNS cancers. Prior board certification by the American Board of Medical Specialties (ABMS) is recommended but optional. The ABMS has twenty-four member specialty boards that certify their members through written and oral examinations and continuing education programs. Many physicians who study neurologic oncology have already been board-certified in their original fields.
Services and procedures performed: Neuro-oncologists provide therapy for primary and metastatic brain, spine, and peripheral and central nervous systems tumors. Tumors are diagnosed using modern neuroimaging techniques such as positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) to facilitate diagnostic biopsies and appropriate treatment. The imaging studies are usually interpreted with the assistance of a neuroradiologist.
Treatment may include chemotherapy, radiation therapy (conventional, brachytherapy, or radiosurgery), neurosurgery, or a combination of these treatments. Whenever possible, and especially in the case of rapidly growing, aggressive disease, neurosurgical of the tumor is the treatment of choice, usually followed by chemotherapy, radiotherapy, or both. In the case of inoperable cancers, a combination of and radiotherapy may be the treatment of choice. Chemotherapy involves the use of chemical compounds that are toxic to cells. Traditional chemotherapeutic agents include carmustine (BCNU, or BiCNU), lomustine (CCNU, Gleostine, or CeeNU), and a combination of procarbazine, CCNU, and vincristine known as PCV.
Chemotherapy may be administered orally (for example, Temodar (temozolomide) tablets), intravenously (most agents), or through direct surgical implantation of a chemotherapeutic wafer, usually placed in the tumor cavity after resection. Chemotherapy is typically performed in stages over time. Conventional radiotherapy alone or in combination with chemotherapy, surgery, or both may also be administered.
Radiotherapy uses high-energy external X-rays, gamma rays, or charged particles (electron or proton beams) to damage important biological molecules in tumor cells. If enough damage occurs in a cell's chromosomes, cell death (or apoptosis) will occur. Radiotherapy is generally administered at regular intervals over a several-week course. Brachytherapy is a type of radiotherapy in which radioactive material (most often iridium-192), usually in the form of a tiny pellet or seed, is inserted inside or next to the tumor. Brachytherapy is commonly used to treat localized cancer. Radiosurgery is a variation of radiotherapy that uses highly focused gamma rays to kill cancerous cells. Radiosurgery is performed in a single session.
Neurosurgery is the incision and excision of cancerous tissue. Tumors may be completely or partially resected depending on their location and accessibility. The tumor may be approached via an open surgical procedure such as a craniotomy or an endoscopic approach such as a transnasal (through the nose) route. Another U.S. Food and Drug Administration-approved technique is convection-enhanced delivery, which involves the implantation of a catheter into the tumor and the slow infusion of a chemotherapeutic agent into the brain or tumor. Convection-enhanced delivery relies on a small, continuous pressure gradient to infuse the chemotherapeutic agent up to several centimeters from the infusion site.
Related specialties and subspecialties: The primary care physician is often the source of the referral to the neuro-oncologist and thus may remain involved in some way with the patient’s care. Other comorbidities may necessitate the continued involvement of the primary physician and other physicians outside the general field of neurologic oncology. For cancer treatment, the practice of neurologic oncology involves the cooperation of a multidisciplinary team, which, depending on the course of treatment chosen, may include neuro-oncology nurse specialists, medical oncologists, neurologists, neurosurgeons, radiation oncologists, neuroradiologists, neuropathologists, neuroanesthesiologists, and pain management personnel, rehabilitative and cognitive physicians, neuropsychologists and psychiatrists, palliative care specialists, and hospice care providers. All team members will have expertise in a neuro-related or oncologic specialty. If the treatment chosen does not involve surgery, neurosurgeons and neuropathologists are not needed. If the treatment succeeds, palliative care specialists and hospice workers are unnecessary.
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