What leads to brain tumors? Here’s why they’re relatively rare.
Tumors are often misunderstood medical conditions. While it’s not pleasant to be diagnosed with one, many people are unaware that a tumor is simply a mass formed by a cluster of abnormal cells. These masses can grow to significant sizes, but they can also be tiny—small enough that what seems like a strange pimple or mole might be a tumor, which is why doctors may suggest consulting a dermatologist for evaluation.
The primary concern regarding tumors is whether they are cancerous or benign. Thankfully, around 90% of tumors turn out to be benign.
Among the different kinds of tumors, malignant brain tumors are among the least common. “Fewer than 1% of the population will receive a diagnosis of a malignant brain tumor at some point in their lives,” states Dr. Marissa Barbaro, a neuro-oncologist at the Perlmutter Cancer Center at NYU Langone Hospital—Long Island.
Nevertheless, knowing what brain tumors are and their causes can aid in taking preventive measures.
Understanding brain tumors
Similar to other tumors, brain tumors arise from abnormal cell growth, and the quantity of these cells influences the tumor’s overall size. Benign brain tumors typically grow slowly and do not spread to other body parts, making them easier to identify with well-defined borders.
In contrast, malignant brain tumors can proliferate rapidly, often infiltrating nearby brain tissues. “These tumors tend to be more aggressive and can present significant treatment challenges,” explains Dr. Andrea Cercek, a gastrointestinal oncologist and co-director at the Center for Young Onset Colorectal and Gastrointestinal Cancers at Memorial Sloan Kettering Cancer.
Barbaro mentions two primary types of brain tumors: primary brain tumors, which originate in the brain itself, and secondary brain tumors, which are tumors that spread to the brain from other cancer sites like lung or breast cancer. Secondary tumors are more prevalent than primary brain tumors, “with only about 90,000 new diagnoses of primary brain tumors annually,” she elaborates.
Regardless of whether a brain tumor is primary or secondary, it carries risks. Although malignant tumors are more alarming because of their aggressive nature and difficulty in containment, benign brain tumors can also pose significant concerns, particularly when located in the brain.
This is due to their potential to compress critical brain areas, leading to a wide range of complications. “The brain regulates essential bodily functions such as thought, memory, emotion, sensory perception, motor skills, vision, breathing, temperature control, and hunger,” remarks Dr. Julie Gralow, chief medical officer at the American Society of Clinical Oncology. “If a mass develops in the skull and increases pressure on the brain, it can disrupt these functions, potentially resulting in issues like muscle weakness, difficulty speaking, or seizures,” she adds.
Due to these risks, doctors typically recommend the surgical removal of both malignant and benign brain tumors upon discovery.
What are the causes of brain tumors?
The factors leading to tumor formation in the brain can be similar to those seen in other body regions. One significant contributor is age, as the immune system’s efficiency decreases with increasing age. A compromised immune system results in ineffective recognition and elimination of tumor cells, which explains why brain tumors are more frequently diagnosed in older adults compared to younger individuals and those with immune system disorders.
Further research is still needed, but certain environmental factors such as exposure to radiofrequency energy, electromagnetic waves, and air pollution might also play a role. The most clearly identified risk factor related to the environment is exposure to ionizing radiation, especially during childhood. “For instance, children treated with radiation to the head for diseases like leukemia or individuals exposed during a nuclear incident are at increased risk,” explains Barbaro.
Additionally, Gralow states that family history and genetic factors might heighten the risk of developing brain tumors, along with the possibility of previous brain injuries and dietary influences.
Can brain tumors be avoided?
Although it’s impossible to completely prevent tumors, certain measures can lower the likelihood of developing a brain tumor. Recommended steps include avoiding smoking, limiting exposure to high levels of radiation, and steering clear of environmental hazards. The American Cancer Society advises that children and pregnant women should avoid unnecessary head CT scans.
Maintaining a robust immune system is also crucial; factors like adequate sleep, stress reduction, and a nutritious diet can help enhance immune health.
How brain tumors are detected
In cases where brain tumors are not prevented and occur, some symptoms that might reveal their presence include speech difficulties, weakness or numbness on one side of the body, persistent headaches, vision changes, and balance problems. If these symptoms worsen or become ongoing, Gralow advises seeking medical evaluation.
Once a cell growth is detected in the brain area, malignancy is usually determined through pathology reports or biopsies, according to Barbaro. “When this happens,” she explains, “advanced molecular testing and an in-depth pathological analysis of the tissue are performed to ascertain whether it is benign or malignant.”
the particular type of tumor and its anticipated level of aggressiveness.