Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by challenges in social interaction, communication, and the presence of restricted, repetitive patterns of behavior, interests, or activities. Individuals with ASD may also have varying ways of paying attention, learning, or moving.
This developmental disability affects people worldwide. According to the Centers for Disease Control and Prevention (CDC), an estimated 5.4 million adults in the United States have ASD. It is a lifelong condition with no cure, suggesting people with ASD may need ongoing services and support systems.
Understanding the Link Between Autism and Cancer
While autism and cancer are distinct conditions, recent research implies a potential association between them. This connection raises intriguing questions about the underlying mechanisms and implications for people with autism. Exploring the relationship between these conditions is crucial to improve healthcare outcomes and address the unique needs of this growing population.
1. Genetic Factors Contributing to Autism and Cancer
Research suggests that certain gene mutations and chromosomal abnormalities can increase susceptibility to both autism and cancer. For example, one form of autism results from a mutation in the PTEN gene, which is the same mutation linked to cancers of the brain, skin, thyroid, breast, colon, and many more. Individuals with this mutation possess a higher chance of developing breast cancer in their lifetime. The higher incidence rate is due to normal PTEN gene stopping cell division. When the mutation is present, the cells no longer have this vital function.
According to an article published in the New York Times, 10 percent of children with the PTEN mutation also have autism, insinuating that those with ASD have an elevated risk of developing cancer.
2. Shared Biological Pathways and Molecular Mechanisms
While research is ongoing and the precise nature of this connection is not fully understood, studies have provided insights into potential overlapping mechanisms. Aside from mutation in the PTEN gene, other key points include:
- Abnormal cellular processes: Cellular stress and apoptosis (programmed cell death), disruptions in cell proliferation, and signaling pathways are prevalent in both conditions. These irregularities indicate potential shared molecular mechanisms underlying the development of autism and cancer.
- Immune system dysfunction: The medical and scientific communities have observed inflammation and immune dysregulation in individuals with ASD. Both are well-known risk factors for cancer development and progression.
3. Environmental Factors
Environmental factors, such as prenatal and lifetime exposures to carcinogens, can lead to cancer development over time. For example, chronic exposure to harmful chemicals and air pollutants during critical periods of fetal development or throughout life may increase the risk of cancer, regardless of whether a person has autism.
Common Cancers in People With Autism
Below are the top seven most commonly occurring cancers in people with autism. Note that the majority, if not all, of the malignant disorders mentioned correlate with the genetic factors, biological pathways, and/or molecular mechanisms discussed above.
1. Brain Tumors
Researchers found a higher risk of brain tumors in individuals with autism. In fact, as noted in the above article from the New York Times, about half of children with PTEN gene mutations can develop large tumors in several organs, including the brain. Unfortunately, the exact reasons for this link are not fully understood.
Those with ASD have an increased risk of developing leukemia, particularly acute lymphoblastic leukemia (ALL). Again, the underlying reasons for this association remain unclear, but genetic predisposition, abnormal immune responses, or shared environmental exposures could play a role.
3. Breast Cancer
According to research from the Cancer Support Community, individuals with autism and PTEN gene mutation have an 85 percent chance of developing breast cancer.
4. Prostate Cancer
Researchers from the Cleveland Clinic in Ohio, USA concluded that those with autism have a lifetime cancer risk of 1.3 percent compared to 3.9 percent in the control group. They found that three of the 18 children have PTEN gene mutations, which contribute to dozens of cancer incidences, including of the prostate.
5. Gastrointestinal (GI) Cancers
Autism spectrum disorder is associated with significant rates of genomic aberrations, including chromosomal rearrangements and de novo copy-number variants (MdnCNV). These observations are reminiscent of malignancy – including cancers that occur in the stomach, colon, and pancreas – a disease where genomic rearrangements play a role.
6. Thyroid cancer
According to a 2017 study, folate receptor α (FRα) autoantibodies (FRAAs) may be responsible for the prevalence of thyroid dysfunction in children and adults with ASD. Additional studies have also indicated a potential link between thyroid abnormalities and cancer risk. In particular, research shows that people with autism and birth defects had a twofold higher risk of cancer compared to those without ASD.
7. Kidney Cancer
In 2021, a group of researchers identified the presence of neurodevelopmental impairments as a factor associated with pediatric kidney disease and bladder dysfunction. This connection poses additional challenges for clinicians and the loved ones of those with ASD, as some studies show that people with these conditions, especially those with kidney disease, may have a higher risk for kidney cancer due to long-term dialysis and immunosuppressant medication intake.
In a 2022 study published in the Annals of Oncology, clinical investigators found an overall increased risk of any cancer among those with autism. In other words, although the seven other cancers mentioned are more common, those born with ASD are at risk of any cancer, including general (lung, liver, etc.) and gender-specific (ovaries, testes, etc.) malignancies.
How Common Is Cancer in People With Autism?
Keep in mind that having ASD does not mean an individual will develop cancer. Autism spectrum disorder and cancer are separate conditions with different causes and risk factors. While some studies have highlighted an association between the two, the overall risk of cancer in individuals with autism remains low.
The Bottom Line
The potential link between autism and cancer opens up new avenues of research, underscoring the importance of comprehensive healthcare for people with autism and cancer. Shared genetic and environmental factors, as well as overlapping biological pathways, may be the bridge between these conditions. Understanding these connections can empower early detection and personalized treatment plans, improving outcomes for anyone with autism and cancer.
Continued research is also necessary to deepen our understanding and fulfill the unique needs of this population, leading to better healthcare and support for all with ASD.
Before we end our discussion, remember that events like Autism Awareness Month (April) and Autistic Pride Day (June 18) serve as reminders to promote acceptance, understanding, and support for those with ASD. By raising awareness and advocating for inclusive healthcare, each of us can contribute to a society that embraces neurodiversity.
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