There are twelve major types of childhood cancers. Of these, leukemias and brain cancers comprise more than half of all new cases. 1
 Approximately 4,000 children are diagnosed with brain tumors each year, and about 72% of those children are younger than 15.2  
Click here to read about Lindsey's tumor.

 When the body's cells grow old or get damaged, they normally die and are replaced by new, healthy cells. When this process goes wrong, new cells form when the body (or, in this case, the brain) doesn't need them, and the old/damaged cells don't die as they should. This build-up of extra cells often forms a mass of tissue, also known as a tumor.
    Brain tumors are either benign or malignant. Benign tumors do not contain cancer cells; malignant tumors do. However, some benign tumors do have the potential to become malignant, and can be just as dangerous if the tumor grows large enough to press on vital areas of the brain.
    Pediatric brain tumors are typically primary, meaning they were not formed as a result of cancer cells elsewhere in the body. The cause for some pediatric brain tumors is still unknown, but research has shown that the majority are formed as a result of genetic abnormalities within the tumor cells. Certain types of brain tumors are more common in children due to the fact that they are made up of "young cells", but a child can develop any type of brain tumor. For more information regarding pediatric brain tumors, visit MedLinePlus: Childhood Brain Tumors.

MEDULLOBLASTOMAS: These are one of the most common types of pediatric brain tumor, typically occurring between the ages of 2 and 6 years old. Medulloblastomas are more common in boys than in girls, and are found in the cerebellum (the part of the brain involved in motor function and balance).
BRAIN STEM GLIOMAS: These tumors occur in the glial (supportive) cells of the brain. There are several different types of gliomas; one of the most common gliomas are astrocytomas. Gliomas make up the most common groups of brain tumors in children, most common in children ages 3 to 12.
EPENDYMOMAS: Ependymomas are the third most common type of pediatric brain tumor, with about 140 new cases occurring each year. These tumors are uncommon, affecting around 200 children and young adults each year.

See below
AT/RT is a rare type of pediatric tumor that affects the central nervous system, and is most commonly diagnosed in children under the age of three.

Lindsey was diagnosed with a rare, inoperable type of glioma known as a diffuse intrinsic pontine glioma (DIPG).
Diffuse intrinsic pontine gliomas develop in the pons (middle) area of the brainstem. This area is critical for many vital functions including breathing and heart rate. DIPGs are one of the most devastating and deadly of all pediatric gliomas, with approximately 200 children diagnosed each year. The average age affected is 5-9 years old.
     DIPG diagnosis carries a grim prognosis, with a typical rate of survival of 9 months. The one year survival rate for this tumor is around 30%, and less than 10% of children will live 2 years following diagnosis. Complete survival of DIPG is even more rare.
    Symptoms of DIPG typically include headaches, nausea, vomiting (particulary in the morning), loss of coordination and vision changes. However, these symptoms do not usually present themselves until the tumor is well advanced, making early diagnosis extremely difficult.
    Because of this tumor's sensitive location, surgery is highly dangerous and is not a treatment option. Typically, DIPG patients go through a six to nine week course of radiation therapy, and in some cases, this can cause a suppression of symptoms. Unfortunately, this is temporary and symptoms return, usually within 6 to 9 months, and the tumor begins to progress rapidly. Occasionally, some children will also undergo chemotherapy treatments, but the majority of these are experimental and done through clinical trials. As of today, there are no "real" treatments for DIPG. Chemo and radiation are unsuccessful in removing the tumor, and are almost always done as a means to try and extend the child's life just a little longer.
       To put it bluntly, DIPG is one of the most cruel and devastating diseases a child could ever be faced with.  The tumor is extremely debilitating, robbing the child of his or her motor functions, eventually leaving them partially paralyzed. The child loses the ability to walk, use one or both of their hands, sit up, speak and see. They are left completely bedridden and eventually the ability to eat and even breathe is soon lost. The most horrifying aspect of these effects is the fact that the child's cognitive functions remain unharmed, so that they are fully aware of what is happening to them. They are left completely helpless and over time, can no longer even verbalize their needs and feelings. Imagine being 5 years old, knowing that at one time in the very recent past you were able to color, and go outside and run and play (and knowing that you should still be doing all of those things), and now you are left lying in a bed, all night and day, not even understanding what is happening to you, and being helpless to do anything about it. To me, that is one of the most cruel things that could ever happen to a child- no matter what age they are. 
    As if all of these things weren't enough, these children's bodies undergo countless physical traumas in their search to get better- daily radiation treatments (most younger patients must be sedated for this), chemotherapy that leaves them sick, weak and bald, steroids that leave their faces and bodies swollen and misshapen, surgically implanted IV ports so that they can receive their daily medications (often, these are extremely uncomfortable for children), feeding tubes when they lose the ability to eat on their own... it goes on and on. Even after all of this, their treatments eventually fail and they succumb to the disease that took everything away from them.
    This is a disease that "strikes" at a time when children are supposed to be innocent, and carefree; unaware of all the dangers of the world and the bad things that can happen. They should be able to color and draw, run and play, go to school... all of those little things that make children just that... children.
    We need more awareness of the disease, we need advancements in treatment, we need advancements in research... we need a cure.  Not just for DIPG, but for all pediatric brain tumors, for all childhood cancers.