Brain metastasis

Source: Wikipedia, the free encyclopedia.
colorectal carcinoma metastasis to the cerebellum. HPS stain
.

A brain metastasis is a

primary tumors that originate in the brain are less common.[4] The most common sites of primary cancer which metastasize to the brain are lung, breast, colon, kidney, and skin cancer. Brain metastases can occur months or even years after the original or primary cancer is treated. Brain metastases have a poor prognosis for cure, but modern treatments allow patients to live months and sometimes years after the diagnosis.[5]

Symptoms and signs

Brain metastasis in the right cerebral hemisphere from lung cancer shown on T1-weighted magnetic resonance imaging with intravenous contrast.

Because different parts of the brain are responsible for different functions, symptoms vary depending on the site of metastasis within the brain. However, brain metastases should be considered in any cancer patient who presents with neurological or behavioral changes.[6]

Brain metastases can cause a wide variety of symptoms which can also be present in minor, more common conditions. Neurological symptoms are often caused by

increased intracranial pressure,[7] with severe cases resulting in coma.[8]
The most common neurological symptoms include:

  • New onset headaches: headaches occur in roughly half of brain metastasis patients, especially in those with many tumors.[6]
  • Paresthesias: patients often present with (hemiparesis), or weakness on only one side of the body, which is often a result of damage to neighboring brain tissue.[7]
  • Ataxia: when metastasis occurs to the cerebellum, patients will experience various difficulties with spatial awareness and coordination.[9]
  • Seizures: when present, often indicates disease involvement of the cerebral cortex.[10]

Causes

The most common sources of brain metastases in a

Memorial Sloan–Kettering Cancer Center were:[11]

Lung cancer and melanoma are most likely to present with multiple metastasis, whereas breast, colon, and renal cancers are more likely to present with a single metastasis.[3]

Diagnosis

Resected fragments of a brain tumor, and in this case the very dark appearance supports a diagnosis of metastatic pigment-forming melanoma.

Brain imaging (

MRI) is needed to determine the presence of brain metastases.[6] In particular, contrast-enhanced MRI is the best method of diagnosing brain metastases, although primary detection may be done using CT.[10] Biopsy is often recommended to confirm diagnosis.[6]

The diagnosis of brain metastases typically follows a diagnosis of a primary cancer.[10] Occasionally, brain metastases will be diagnosed concurrently with a primary tumor or before the primary tumor is found.

In the setting of brain metastasis due to malignant melanoma, MRI imaging showed high T1 and low T2 intensity due to the deposition of melanin in the brain. In susceptibility weighted imaging (SWI), it usually shows abnormal SWI hypointensity in larger proportion than brain metastasis caused by breast carcinoma.[12]

Treatment

Treatment for brain metastases is primarily

Gamma Knife therapy) may be attempted.[1]

Symptomatic care

Symptomatic care should be given to all patients with brain metastases, as they often cause severe, debilitating symptoms. Treatment consists mainly of:

  • emesis. Dexamethasone is the corticosteroid of choice.[10] Although neurological symptoms may improve within 24 to 72 hours of starting corticosteroids, cerebral edema may not improve for up to a week.[15] In addition, patients may experience adverse side effects from these drugs, such as myopathy and opportunistic infections, which can be alleviated by decreasing the dose.[15]
  • Anticonvulsants – Anticonvulsants should be used for patients with brain metastases who experience seizures, as there is a risk of status epilepticus and death.[16] Newer generation anticonvulsants including Lamotrigine and Topiramate are recommended due to their relatively limited side effects.[16] It is not recommended to prophylactically give anti-seizure medications when a seizure has not yet been experienced by a patient with brain metastasis.[16]

Radiotherapy

Radiotherapy plays a critical role in the treatment of brain metastases, and includes whole-brain irradiation, fractionated radiotherapy, and radiosurgery.[6] Whole-brain irradiation is used as a primary treatment method in patients with multiple lesions and is also used alongside surgical resection when patients have single and accessible tumors.[6] However, it often causes severe side effects, including radiation necrosis, dementia, toxic leukoencephalopathy, partial to complete hair loss, nausea, headaches, and otitis media.[17] In children this treatment may cause intellectual impairment, psychiatric disturbances, and other neuropsychiatric effects.[18] Results from a 2021 systematic review on radiation therapy for brain metastases found that despite much research on radiation therapy, there is little evidence to inform comparative effectiveness and such patient-centered outcomes as quality of life, functional status, or cognitive effects.[1] In addition, whole-brain irradiation in combination with surgery showed no effect on overall survival when compared to whole-brain irradiation alone as demonstrated by a systematic review by the Agency for Healthcare Research and Quality.[1]

Surgery

Brain metastases are often managed surgically if they are accessible. Surgical resection followed by

stereotactic radiosurgery or whole-brain irradiation deliver superior survival compared to whole brain irradiation alone.[6] Therefore, in patients with only one metastatic brain lesion and controlled or limited systemic disease, a life expectancy of at least 3 months with maintenance of performance status might be expected.[19]

Chemotherapy

non-small cell lung cancer (NSCLC; ALK-positive), a type of cancer which often metastasizes to the brain, whose condition worsened after use or were unable to take another medication, Xalkori (crizotinib).[23]

Immunotherapy

anti-CTLA-4, appears to be effective in some patients with brain metastases especially when these are asymptomatic, stable and not previously treated.[24] In 2022, OMICs-based approaches such as single-cell and bulk RNA-sequencing revealed molecular subgroups in melanoma brain metastases (MBM) that may explain the variable response of MBM to therapeutic interventions.[25][26]Moreover, methylome and transcriptome profiling of MBM revealed immune cell and microglia-enriched tumor subsets showing favorable outcome.[27]

Prognosis

The prognosis for brain metastases is variable; it depends on the type of primary cancer, the age of the patient, the absence or presence of extracranial metastases, and the number of metastatic sites in the brain.

Karnofsky performance score is used for a more specific prognosis.[6]

Epidemiology

It is estimated that the worldwide

incidence rate for brain metastases lies around 9% to 17%, based on the region of diagnosis.[28][29] However, the baseline incidence rate of brain metastases were found to increase with improvements to brain imaging technology.[30] Approximately 5-11% of brain metastasis were found to be deadly at 30 days, and 14 - 23% were found to be deadly at three months.[31]

More cases of brain metastases were found in

intracranial
areas within the context of extracranial diseases.

Both population studies and autopsy studies have historically been used to calculate the incidence of brain metastases. However, many researchers have stated that population studies may express inaccurate data for brain metastases, given that surgeons have, in the past, been hesitant to take in patients with the condition. As a result, population studies regarding brain metastases have historically been inaccurate and incomplete.[39][40]

Advances in systemic treatments of brain metastases, such as

surgical resection has led to an increase in median survival rate of brain metastases patients.[41]

See also

References

  1. ^
    S2CID 236256085
    .
  2. ^ a b c d Tse V (10 November 2009). "Brain Metastasis". Medscape. Retrieved 13 January 2010.
  3. ^ a b "Metastatic Brain Tumors" (PDF). Archived from the original (PDF) on 29 August 2017. Retrieved 13 August 2017.
  4. ^ "Tumor Types - National Brain Tumor Society". National Brain Tumor Society. Retrieved 1 August 2017.[permanent dead link]
  5. ^ "Radiation Therapy for Brain Metastases: What are brain metastases?". Archived from the original on 2010-04-06. Retrieved 2010-03-17.
  6. ^ a b c d e f g h i j Loeffler JS. Wen PY, Eichler AF (eds.). "Epidemiology, clinical manifestations, and diagnosis of brain metastases". UpToDate. Retrieved 2 August 2017.
  7. ^
    PMID 11589063. Archived from the original
    on 2022-10-04. Retrieved 2017-08-13.
  8. ^ "Metastatic Brain Tumors". American Association of Neurological Surgeons. Retrieved 3 August 2017.
  9. ^ "Metastatic Brain Tumors". Memorial Sloan Kettering Cancer Center. Retrieved 3 August 2017.
  10. ^
    PMID 10442342
    .
  11. ^ Ts V (10 November 2009). "Brain Metastasis - Morbidity/Mortality". Medscape. Retrieved 13 January 2010.
  12. PMID 29307364
    .
  13. PMID 30053879
    .
  14. PMID 36435874
    .
  15. ^ a b Drappatz J. Wen PY, Eichler AF (eds.). "Management of Vasogenic Edema in Patients with Primary and Metastatic Brain Tumors". UpToDate. Retrieved 2 August 2017.
  16. ^ a b c Drappatz J. Avila EK, Schachter SC, Wen PY, Dashe JF (eds.). "Seizures in Patients with Primary and Metastatic Brain Tumors". UpToDate. Retrieved 2 August 2017.
  17. ^ Loeffler JS. Wen PY, Eichler AF (eds.). "Overview of the Treatment of Brain Metastases". UpToDate. Retrieved 2 August 2017.
  18. ^ "What are the real benefits versus risks of preventative brain radiation for patients with non-small cell lung cancer?" (PDF). Archived from the original (PDF) on 2010-06-13. Retrieved 2010-03-17.
  19. ^ "IIS7". Archived from the original on 2010-01-29. Retrieved 2010-01-16.
  20. PMID 22696370
    .
  21. ^ "Definition of intrathecal chemotherapy". 2011-02-02. Retrieved 2017-08-13.
  22. PMID 24998288
    .
  23. ^ "FDA approves new oral therapy to treat ALK-positive lung cancer". FDA. 11 December 2015. Retrieved 4 August 2017.
  24. S2CID 3782427
    .
  25. S2CID 250343194
    .
  26. PMID 36435874
    .
  27. PMID 38386085
    .
  28. ISBN 9780470753064
  29. OCLC 805657369
    .
  30. PMID 15254054
    .
  31. PMID 23717790
    .
  32. PMID 9010115
    .
  33. PMID 8708681
    .
  34. PMID 21244695
    .
  35. S2CID 19575548
    .
  36. PMID 10098435
    .
  37. S2CID 23306094
    .
  38. PMID 15254054
    .
  39. S2CID 20786479
    .
  40. S2CID 43324791
    .
  41. PMID 24311640
    .
Retrieved from "https://en.wikipedia.org/w/index.php?title=Brain_metastasis&oldid=1215720983"