Neuroscience Class: Glial Cells and Tumors

Management of Patients with Brain Tumors

• Brain tumors are diverse, with over 120 types and cysts.
• Primary tumors originate from brain/spinal cord cells, while secondary/metastatic tumors derive from other parts of the body.
• Secondary tumors are more frequent than primary tumors, originating from locations such as breast, lung, or GI tract.
• Tumor cells can enter the brain via the bloodstream, cerebrospinal fluid (CSF), or lymphatic system.

Etiology

• The precise cause of primary brain tumors is often unknown.
• Ionizing radiation is a strong risk factor.
• Other contributing factors include genetics and environmental elements.

Epidemiology

• The incidence of brain tumors varies by age.
• Adolescents and young adults frequently develop primary brain tumors, with a focus on low-grade gliomas.
• Adults (30-40 years and older) demonstrate an increase in metastatic brain tumors.
• Glioblastoma is the common malignant primary brain tumor in adults, with a median diagnosis age of 64.
• Meningiomas and glial tumors account for most primary brain tumors in adults.

Incidence of Brain Tumors by Location

• Location significantly impacts tumor incidence.
• Specific areas like the frontal lobe (26%), temporal lobe (30%), and parietal lobe (12%) experience varying frequencies of tumor occurrences.

Benign vs. Malignant Tumors

• Benign tumors rarely recur after removal, exhibit well-defined borders, and do not spread.
• They typically exert pressure on brain tissues.
• Malignant tumors have a high potential for return, have unclear borders, and can spread.
• They rapidly grow and invade healthy brain tissue. They also spread to other parts of the body in certain cases.

Risk Factors

• The origin of primary brain tumors is frequently unknown.
• Ionizing radiation is a major risk factor.
• Genetic and environmental factors may increase risks.

Clinical Manifestations

• The symptoms of brain tumors depend on their position and size, as well as the impact on adjacent structures.
• These may include headache, nausea/vomiting, seizures, motor weakness (ataxia, paralysis, hemiparesis, aphasia), mental status changes, memory loss, visual disturbances, hormonal effects (with pituitary adenomas), hearing loss, tinnitus, vertigo (in the case of acoustic neuromas), and increased intracranial pressure (ICP) symptoms.

Brain Lobes and Function

• Different brain regions have varying roles.
• The frontal lobe involves executive functions, like planning, decision-making.
• The parietal lobe is involved in sensory information processing and spatial awareness.
• The temporal lobe handles hearing, memory, and language processing.
• The occipital lobe focuses on visual processing.
• The cerebellum aids in motor coordination, balance, and movement.
• The brain stem manages functions like breathing and heart rate.

Brain Tumor Classification

• Classification considers the type of tissue involved, the location of the tumor, and the tumor grade (determined by biopsy).
• Tumor grading signifies malignancy levels, from Grade 1 (well-differentiated) to Grade 4 (undifferentiated and highly malignant).
• WHO criteria (for CNS) for tumor grading specify microscopic appearance and rate of growth in tumors.

Tumor Grading

• Tumor grading is based on microscopic appearance and growth behavior.
• Specific grades are identified according to WHO guidelines.

Clinical Presentation

• Brain tumors produce symptoms due to local invasion, adjacent structure compression, and increased intracranial pressure (ICP).
• The clinical manifestations correlate with the involved brain areas' functions.
• Patients require a detailed medical history, neurological examination, and diagnostic neuroimaging studies for proper evaluation.

Pathophysiological Results of Brain Tumors

• Increased intracranial pressure (ICP), cerebral edema/inflammation, seizure activity, obstruction of cerebral spinal fluid (CSF) flow (hydrocephalus), and altered pituitary function/hormonal changes are possible consequences.

Symptoms of Tumors in Different Brain Regions

• Frontal lobe tumors can cause problems with concentration, decision-making, speech/language production, emotions, and behavior.
• Temporal lobe tumors can affect hearing, memory, language understanding, and emotional processing.
• Parietal lobe tumors can impair sensory perception, spatial awareness, and body recognition.
• Occipital lobe tumors can create vision problems, including difficulty recognizing colors or objects.
• Cerebellum tumors cause balance issues, coordination problems, and difficulties with walking and/or speech.
• Brainstem tumors can lead to headaches, balance disturbances, walking difficulty, and facial weakness.

Management

• Management involves surgery, radiation therapy, and chemotherapy, tailored to the tumor type, location, and accessibility.
• Surgery aims to alleviate symptoms and decompress affected areas.
• Radiation therapy is a fundamental treatment component.
• Chemotherapy plays a role, often used concurrently with other treatments.

Intracranial Surgery

• Craniotomy involves opening a portion of the skull to access the brain.
• Burr holes are smaller openings used for diagnosis or surgical exploration.
• Trans-sphenoidal approach is a less invasive technique using the nasal cavity to reach the pituitary gland.

Preoperative Care

• Before surgery, patients need a baseline neurological examination.
• Understanding of the surgery and preparation are crucial.
• Preoperative procedures include medical evaluations and scans.
• Medications like antibiotics and corticosteroids support pre-surgical care.

Drug Therapy

• Medications are used to manage symptoms and prevent complications.
• Analgesics (pain relief), steroids (inflammatory control), anti-seizure drugs, anti-emetics, and muscle relaxants are often used.
• Mannitol can help reduce increased intracranial pressure (ICP).

Postoperative Care

• Postoperative care involves close monitoring for complications like increased intracranial pressure (ICP), cerebral edema, seizures, and infection.
• Supporting respiratory function, controlling pain, and preventing complications are critical.

Nursing Diagnoses

• Common nursing diagnoses focus on issues like ineffective cerebral tissue perfusion, risk for imbalanced body temperature, impaired sensory perception, and changes in body image.

Nursing Interventions

• Nurses implement various interventions, including monitoring vital signs, supporting respiratory function, managing pain, and preventing complications.

Potential Complications

• Potential post-craniotomy complications include increased intracranial pressure (ICP), bleeding, infection, seizures, and fluid/electrolyte imbalances.

Interventions to Maintain Cerebral Perfusion

• Nurses meticulously monitor respiratory status to maintain appropriate oxygen levels.
• Reducing cerebral edema plays a critical role.
• Controlling factors that could raise intracranial pressure (ICP) is a notable intervention.

Interventions (continued)

• Nurses manage various patients' issues by encouraging deep breathing, turning and positioning, using suction if necessary, and offering humidified oxygen.

Preventing Infections

• Assessing the surgical incision and monitoring for signs of infection are crucial.
• Instructions regarding coughing/sneezing are vital.
• Maintaining strict aseptic technique helps minimize infection risk.

Nursing Interventions for Metastatic Brain Tumors

• Implementing a palliative approach is essential and includes measures to provide comfort, maintain functionality, and acknowledge patients' preferences and anxieties.
• Patient and family support is essential.
• Referrals to healthcare providers and other resources that may aid the patient.
• Managing symptom relief is also important.

Improving Nutrition

• Patient-centered dietary plans, incorporating preferred foods and supplements, meet nutritional requirements and promote comfort.
• Thoroughly recording dietary intake is important for monitoring nutritional needs.

Conclusion

• This comprehensive summary provides a detailed overview of brain tumor management, encompassing assessment, diagnosis, treatment (including surgical approaches), nursing care, and potential complications.

Test your knowledge on glial cells and the tumors that arise from them in this quiz. You'll explore different types of glial cells, their functions, and associated brain tumors. Ideal for students studying neuroscience or biology.