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, Among 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.
Medulloblastoma is a type of brain tumor; Specifically, it consists of a malignant brain tumor, that is, cancerous. Let us 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 starts in the cerebellum, located at the bottom and back of the brain. This structure is responsible for coordinating movement and allowing balance. That is why one of its symptoms is 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 common for medulloblastoma to metastasize (spread of the tumor) to other parts of the body.
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 small 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, however, 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 series of frequently occurring symptoms, such as headaches, double vision, dizziness, tiredness …
Alterations also appear in coordination. These result, for example, in 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 involvement of the cerebellum In addition, the person with medulloblastoma may show clumsiness, fall, drop objects, etc.
Another symptom of medulloblastoma is nausea, which usually appears 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 the above plus the following: difficulties walking, back pain and problems controlling the sphincters.
Causes
The origin of the cancer remains unknown. There is talk of a multifactorial cause, which varies depending on the type of cancer The factors related to the etiology of cancer are genetic factors, lifestyle factors (smoking, diet, exercise…), infectious factors, chemical factors (exposure to substances, radiation…), etc.
It is known, however, that cancer is caused by an 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 embryonic tumor; This means that the tumor originates in embryonic stem cells of 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) may 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 alterations.
Treatment
Treatment of medulloblastoma is usually a 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. Extraction 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 remove 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 has the objective of reducing 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.
This treatment option consists of administering certain drugs with the aim of killing cancer cells or to prevent them from continuing to divide. It is usually administered through an injection into a vein (so-called intravenous chemotherapy), both in children and adults, although orally administered drugs (pills) are also used.
Chemotherapy is generally used after surgery to remove the tumor, and is usually combined with radiotherapy, with the aim of eliminating any remaining tumor that may have remained.
4. Radiotherapy
Radiotherapy, like chemotherapy, is widely used in patients with different types of cancer. It consists of administering high doses of radiation (X-ray or other) with the aim of killing cancer cells and reducing or completely destroying medulloblastoma, as well as stopping the proliferation of cells.
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 probability of surviving medulloblastoma It will vary greatly depending on the type of tumor, age of appearance, treatment used, affected areas, etc
Additionally, the survival rate changes whether or not the tumor has spread to the spinal cord; In this way, if it has not expanded, the survival rate is around 70/80%. If, however, it has expanded, the index is around 60%.
