Medulloblastoma: symptoms, causes and treatment

Cancer encompasses a group of diseases that are caused by a disproportionate proliferation of cells in some organ of the body. Cancer affects both adults and children. Specifically, in the pediatric population, Within brain tumors, the most common cancer is medulloblastoma..

This type of malignant tumor affects the brain and can also reach the spinal cord. In it, embryonic stem cells proliferate excessively. In this article we will learn about its characteristics, causes, symptoms, treatments used to eradicate it, and survival rates.

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Medulloblastoma: characteristics

Medulloblastoma is a type of brain tumor; Specifically, it consists of a malignant brain tumor, that is, cancerous. Let's keep in mind that tumors are excessive and abnormal proliferations of cells in some organ of the body; Tumors can be benign or malignant (cancer).

Medulloblastoma usually begins in the cerebellum., located in the lower and rear part of the brain. This structure is responsible for coordinating movement and allowing balance. That is why one of its symptoms is the alteration in coordination, gait and balance.

This type of malignant tumor is usually distributed throughout the brain (and even the spinal cord) through cerebrospinal fluid (CSF), a substance that protects these structures. It is not very often that medulloblastoma metastasizes (spreads the tumor) to other parts of the body than here.

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prevalence and distribution

Another characteristic of medulloblastoma is that it is a rare cancer; On the other hand, although it can appear at any age, It is young children who suffer the most (Most medulloblastomas appear before the age of 16).

In the United States, for example, between 250 and 500 new cases of medulloblastoma are diagnosed each year, all of them children. In fact, it is the most common malignant brain tumor in children (between 15 and 25% of cases). Regarding the distribution by sex, it is slightly higher in boys than in girls. In adults, on the other hand, it represents only 1% of brain tumors.

Symptoms

The symptoms of medulloblastoma can vary from person to person. In addition, these can be caused by the medulloblastoma itself, or by the pressure it exerts on the brain. However, there are a number of frequently occurring symptoms, such as headaches, double vision, dizziness, tiredness…

Alterations in coordination also appear. These result, for example, in an unstable gait (especially when the tumor has spread to the spinal cord). Both the alteration in coordination and the unstable gait are related to the affectation of the cerebellum. In addition, the person with medulloblastoma may manifest clumsiness, fall, objects may fall, etc.

Another symptom of medulloblastoma is nausea, which usually occurs in the morning.; on the other hand, vomiting also appears, which gradually worsens in intensity and frequency.

On the other hand, if the malignant tumor has also reached the spinal cord, the symptoms may be above plus the following: difficulty walking, back pain, and trouble controlling sphincters.

Causes

The origin of the cancer remains unknown. There is talk of a multifactorial cause, which varies depending on the type of cancer. Factors related to the etiology of cancer are genetic factors, lifestyle (smoking, diet, exercise...), infectious factors, chemical factors (exposure to substances, radiation...), etc.

It is known, however, that cancer is caused by excessive and abnormal proliferation of cells, which end up invading underlying tissues and even moving to more distant areas (metastasis). It is also known that the normal mechanisms of cell reproduction and division fail.

In the case of medulloblastoma, it is a type of embryonal tumor; this means that the tumor originates from embryonic stem cells in the brain. These cells can synthesize any other type of cell in the body.

Syndromes that increase your risk

We know that medulloblastoma is not hereditary; however, it has been detected how some inherited syndromes (such as Turcot syndrome or Gorlin syndrome) can increase the risk of developing one.

Specifically, Turcot syndrome (also called “brain tumor syndrome”) is characterized by the presence of malignant neoplasms in the Central Nervous System. For its part, Gorlin syndrome involves multiple malignant basal cell tumors and other associated neurological disorders.

Treatment

Treatment of medulloblastoma is usually a surgical surgical procedure to remove the tumor, with subsequent sessions of chemotherapy, radiation therapy, or both. The treatment options that are usually followed are the following:

1. removal surgery

This has the objective of removing the medulloblastoma, and is performed by a neurosurgeon. An attempt will always be made not to damage the tissues adjacent to the tumor. Sometimes it is possible to extract the medulloblastoma completely and sometimes not (when it is located in very deep or delicate structures of the brain).

2. Surgery to reduce CSF

This is intended to reduce the accumulation of cerebrospinal fluid in the brain, which occurs as a consequence of the growth of medulloblastoma. This buildup of CSF puts pressure on the brain, causing hydrocephalus.. This second treatment option is usually combined with the previous one.

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3. Chemotherapy

This treatment option consists of administering certain drugs with the aim of killing cancer cells or prevent them from further dividing. It is usually given through an injection into a vein (called intravenous chemotherapy), both in children as in adults, although oral administration drugs are also used (tablets).

Chemotherapy is generally used after tumor removal surgery, and is It is usually combined with radiotherapy, with the aim of eliminating any remaining tumor that may have meet.

4. Radiotherapy

Radiotherapy, like chemotherapy, is widely used in patients with different types of cancer. It involves administering high doses of radiation (X-rays or other) with the goal of killing cancer cells and shrinking or totally destroying medulloblastoma, as well as stopping cell proliferation.

The disadvantage of this treatment is that it also kills healthy cells, although more and more selective radiotherapies are currently being developed.

Survival rates

The chance of surviving a medulloblastoma It will vary greatly depending on the type of tumor, age of onset, treatment used, affected areas, etc.

Also, the survival rate changes whether or not the tumor has spread to the spinal cord; In this way, in the event that it has not expanded, the survival rate is around 70/80%. If, on the other hand, it has expanded, the rate is around 60%.

Bibliographic references:

• Menon, G., Krishnakumar, K., Nair, S. (2008). Adult medulloblastoma: clinical profile and treatment results of 18 patients. J Clin Neuroscience, 15: 122-126.
• Peris-Bonet, R., Martinez-Garcia, C., Lacour, B., Petrovich, S., Giner-Ripoll, B., Navajas, A., et al. (2006). Childhood central nervous system tumors-incidence and survival in Europe (1978-1997): a report from the Automated Childhood Cancer Information System project. Eur J Cancer, 42: 2064-2080.
• Rodríguez-Mena, R., Barbella-Aponte, R.A., Gallego-Sánchez, J.M. and Barcia-Marino, C. (2011). Adult medulloblastoma: surgical series of 11 cases. Neurosurgery, 22(6): 488-497.