Medulloblastoma is a malignant (cancerous) brain tumor that occurs in the lower part of the brain, known as the cerebellum. The cerebellum is involved in muscle coordination, balance, and movement. Medulloblastoma tends to spread through the cerebrospinal fluid (CSF), the fluid that surrounds and protects the brain and spinal cord. This tumor rarely spreads to other parts of the body [1].
Symptoms
Medulloblastoma is a type of embryonal tumor, a tumor that starts in the fetal cells in the brain. Though medulloblastoma is not inherited, syndromes such as Gorlin's syndrome or Turcot's syndrome might increase the risk of medulloblastoma. Signs and symptoms of medulloblastoma include:
headaches
nausea
vomiting
tiredness
dizziness
double vision
poor coordination and unsteady walk.
These symptoms may be caused by the tumor itself or may be due to the build-up of pressure within the brain. Despite being uncommon, medulloblastoma is the most frequent type of malignant brain tumor in children. Children should be seen at a facility that has a team of pediatric specialists with experience and expertise in treating pediatric brain tumors, access to cutting-edge medical equipment, and expertise in pediatrics [1], [2].
Global perspective
In high-income countries, medulloblastoma accounts for 20%-25% of all pediatric brain tumors and it has a global impact on children's general health. Because of improved treatment options, medulloblastoma survival rates have greatly increased, with a five-year survival rate that ranges from 70% to 85%. The difference in survival rates in low- to middle-income countries, however, ranges from 33% to 73%. The long-term quality of life of survivors around the world may be compromised by social, cognitive, and neurological long-term late consequences [3].
Indian perspective
The incidence of central nervous system tumors in India ranges from 5 to 10 per 100,000 population, making up for 2% of malignancies. The high success rate in the management of medulloblastoma in the Western world is not precisely reflected in developing countries including India. Some of the factors that may help to partially explain this discrepancy in outcomes include socio-demographic differences, healthcare disparities, and a lack of consistency in the delivery of care, has led to vast variability in clinical practice [4].
Treatment
The treatment approaches for medulloblastoma may be determined by tumor size, nature, location, stage, and/or progression, as well as patient age, and overall health status of the patient, . The treatment plan may be decided based on the risk of treatment toxicity (in the case of infants and children under the age of three). A combination of surgical resection, radiation therapy, and chemotherapy is currently used to treat medulloblastoma, which helps to reduce the overall risk of late mortality. Surgical resection of the tumor helps to alleviate elevated intracranial pressure. Following surgery, radiation therapy of the brain and spine (craniospinal irradiation) with various radiation doses is commonly used across medulloblastoma risk groups. Furthermore, chemotherapy is now commonly used as a standard treatment after postsurgical radiation therapy in patients with medulloblastoma since it increases survival and decreases radiation therapy-related side effects, especially in young children [1], [5].
Quality of life (QOL)
Survivors of medulloblastoma experience the physically and mentally debilitating side effects of its treatment, resulting largely in their existence being negatively affected. Nearly 60% of individuals receiving treatment for a brain tumor struggle to maintain their independence, keep their jobs, and establish long-term relationships after the therapy [6].
Almost 80% of survivors have been reported to suffer neurological, cognitive, or endocrinological morbidity following surgery, including intellectual retardation and growth hormone deficiency. In the presence of extraneural metastases and young age, the patient is placed in the high-risk group that experiences a 50% mortality rate. Every patient must undergo a physical and occupational therapy evaluation following surgery [7].
If cerebellar mutism or any other language-processing disorder is suspected, speech therapy should be incorporated. The neurocognitive state of the patient should be assessed before radiation therapy is utilized. A post-therapy evaluation is essential after completing the treatment regime to determine the functional status and quality of life of the patient. Managing the side effects of treatment is known as palliative care or supportive care. Symptomatic management and supporting patients and their families with their non-medical needs are the goals of supportive care, and it is most effective when it begins right after diagnosis. Various types of supportive care are available, including nutrition counseling, relaxation techniques, emotional and spiritual support, and support groups. Many patients may also require educational support after their treatment before returning to school [5], [8].
References
1. “Medulloblastoma - Overview - Mayo Clinic.” https://www.mayoclinic.org/diseases-conditions/medulloblastoma/cdc-20363524 (accessed Jul. 07, 2023).
2. “Medulloblastoma - Childhood - Symptoms and Signs,” Cancer.Net, Jun. 25, 2012. https://www.cancer.net/cancer-types/medulloblastoma-childhood/symptoms-and-signs (accessed Jul. 07, 2023).
3. C. B. de Medeiros et al., “Medulloblastoma has a global impact on health related quality of life: Findings from an international cohort,” Cancer Medicine, vol. 9, no. 2, p. 447, Jan. 2020, doi: 10.1002/cam4.2701.
4. A. Dasgupta, T. Gupta, and R. Jalali, “Indian data on central nervous tumors: A summary of published work,” South Asian J Cancer, vol. 5, no. 3, pp. 147–153, 2016, doi: 10.4103/2278-330X.187589.
5. “Medulloblastoma - Childhood - Types of Treatment,” Cancer.Net, Jun. 25, 2012. https://www.cancer.net/cancer-types/medulloblastoma-childhood/types-treatment (accessed Jul. 07, 2023).
6. A. A. King et al., “Long-term neurologic health and psychosocial function of adult survivors of childhood medulloblastoma/PNET: a report from the Childhood Cancer Survivor Study,” Neuro Oncol, vol. 19, no. 5, pp. 689–698, May 2017, doi: 10.1093/neuonc/now242.
7. A. C. Paulino, “Extraneural Metastasis in Medulloblastoma,” in Tumors of the Central Nervous System, Volume 8: Astrocytoma, Medulloblastoma, Retinoblastoma, Chordoma, Craniopharyngioma, Oligodendroglioma, and Ependymoma, M. A. Hayat, Ed., in Tumors of the Central Nervous System. Dordrecht: Springer Netherlands, 2012, pp. 71–75. doi: 10.1007/978-94-007-4213-0_7.
8. E. M. Wells et al., “Postoperative cerebellar mutism syndrome following treatment of medulloblastoma: neuroradiographic features and origin: Clinical article,” Journal of Neurosurgery: Pediatrics, vol. 5, no. 4, pp. 329–334, Apr. 2010, doi: 10.3171/2009.11.PEDS09131.
