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Nick Cannon's Son's Death From Brain Cancer

— A look at the infant's condition

MedpageToday
A photo of Nick Cannon

In December, comedian, rapper, and TV host Nick Cannon that his 5-month-old son, Zen, had passed away from a malignant brain tumor.

Cannon explained that he and Zen's mother, Alyssa Scott, noticed that Zen's breathing seemed unusual when he was about 2 months old. They also noticed that his head seemed a bit on the large side, but chalked it up to being a "Cannon head." They first believed he had something going on with his sinuses and took him to his pediatrician. They discovered that the swelling of his head was caused by hydrocephalus due to the brain tumor.

Zen immediately underwent surgery to have a ventricular shunt placed to drain the excess cerebrospinal fluid (CSF). While he initially appeared to be improving, things took a turn for the worse by Thanksgiving.

"We'd wake up, and he wouldn't be breathing for maybe five to 10 seconds at a time, and then he'd let out a huge gasp. You could see it frightened him. It was the scariest thing I've ever experienced," Cannon .

While the possibility of chemotherapy was discussed, Cannon and Scott decided to avoid invasive treatments and to concentrate on giving him the best quality of life possible in the short time he had left.

Zen's last day was spent being held by his parents at the beach.

Pediatric Brain Tumors

According to the , primary brain tumors are a diverse group of diseases that together make up the most common solid tumor among children, with the Central Brain Tumor Registry of the United States estimating that approximately 4,300 U.S. children are diagnosed each year.

Brain tumors are classified by histology. Tumor location and extent of spread are also important factors that affect treatment and prognosis. Immunohistochemical analysis, cytogenetic and molecular genetic findings, and measures of proliferative activity are commonly used in diagnosis.

While the cause of most childhood brain tumors remains unknown, germline mutations are now recognized as cancer-predisposing, and are identified in up to 8% of children with cancer.

Both benign and malignant brain tumors can cause symptoms. Infiltration of a brain area, or pressure on that area, causes that section of brain to malfunction. Signs and symptoms will depend on the area of malfunction.

Signs and symptoms of brain tumors include morning headache or headache that goes away after vomiting; frequent nausea and vomiting; vision, hearing, and speech problems; loss of balance and trouble walking; unusual sleepiness or change in activity level; unusual changes in personality or behavior; seizures; and increase in head size due to hydrocephalus.

Hydrocephalus

Hydrocephalus is an abnormal buildup of fluid in the ventricles deep within the brain. This excess fluid causes the ventricles to enlarge, putting pressure on the brain's tissues.

Hydrocephalus can occur at any age, but is most common in infants and older adults.

What Causes Hydrocephalus?

Hydrocephalus may be present at birth or may develop over time as a result of injury or disease. Except for hydrocephalus secondary to physical obstruction of CSF passages, the exact causes of hydrocephalus are still not well understood.

Congenital hydrocephalus

Babies may be born with hydrocephalus or develop the condition shortly after delivery. In these cases, hydrocephalus may be caused by:

  • Inherited genetic abnormalities that block the flow of CSF
  • Developmental disorders such as those associated with birth defects in the brain, spine, or spinal cord
  • Complications of premature birth, such as bleeding within the ventricles
  • Infection during pregnancy that can cause inflammation in the fetal brain tissue, such as rubella

Acquired hydrocephalus

Certain factors can increase the risk of developing hydrocephalus at any age, including:

  • Brain or spinal cord tumors
  • Infections of the central nervous system, such as bacterial meningitis
  • Injury or stroke that causes bleeding in the brain

Symptoms of Hydrocephalus

Infants

The "plasticity" of the infant skull allows the skull to enlarge in the face of hydrocephalus. Other than a change of head size (which is normally large in proportion to the body), additional symptoms in an infant may be delayed until the ventricles have become quite large.

Signs and symptoms of hydrocephalus in infants include:

  • A rapid increase in head size
  • An unusually large head
  • A bulge on the soft spot on the top of the head
  • Vomiting
  • Problems sucking or feeding
  • Sleepiness
  • Irritability
  • Eyes that are fixed downward (also called "sun setting") or not able to turn outward
  • Seizures

Older children

Older toddlers and young children have fused skull bones, so increases in CSF will cause more intracranial pressure and resultant symptoms earlier compared with infants.

Symptoms in older children include:

  • Headache
  • Blurred or double vision
  • Nausea or vomiting
  • Problems with balance
  • Slowing or loss of developmental progress like walking or talking
  • Vision problems
  • Decline in school performance
  • Poor coordination
  • Loss of bladder control and/or frequent urination
  • Difficulty remaining awake or waking up
  • Sleepiness
  • Irritability
  • Changes in personality or cognition, including memory loss

Treatment of Hydrocephalus

In patients with hydrocephalus, immediate treatment to lower intracranial pressure should be initiated. Underlying conditions that caused it must also be detected and treated.

Hydrocephalus is treated with one of two surgical options. In one option, a shunt is surgically inserted into the brain and connected to a flexible tube placed under the skin to drain the excess fluid into either the chest cavity or the abdomen, so that it can be absorbed by the body.

The other option is endoscopic third ventriculostomy, which improves the flow of CSF out of the brain. A tiny hole is made at the bottom of the third ventricle and the CSF is diverted there to relieve pressure. Sometimes this is done in conjunction with choroid plexus cauterization to try and decrease the production of CSF. Choroid plexus cauterization uses an electric current to burn the choroid plexus in the lateral ventricles of the brain, so that it produces less CSF.

Shunt systems generally function well, but they can fail to properly drain the CSF due to mechanical failure or infection. When this occurs, the CSF once again begins to build up in the brain and earlier symptoms may recur. To reduce the buildup of CSF, the clogged shunt system is replaced to restore drainage.

Shunts require monitoring and regular medical checkups. Multiple surgeries may be needed to repair or replace a shunt throughout a person's lifetime; this is especially true in children who will need revisions to the shunt as they grow.

Michele R. Berman, MD, is a pediatrician-turned-medical journalist. She trained at Johns Hopkins, Washington University in St. Louis, and St. Louis Children's Hospital. Her mission is both journalistic and educational: to report on common diseases affecting uncommon people and summarize the evidence-based medicine behind the headlines.