Costello Syndrome

What Costello Syndrome Means

Costello syndrome is a rare genetic disorder caused by mutations in the HRAS gene. This gene helps control how cells grow and divide. When it is mutated, it can cause cells to grow too much or in an abnormal way. People with Costello syndrome often have distinctive facial features, loose folds of skin (especially on the hands and feet), unusually flexible joints, heart problems, and delays in learning and development. Infants may be larger than average at birth but tend to grow more slowly and have feeding difficulties. The syndrome affects many parts of the body and is part of a group of conditions called RASopathies, which share similar genetic causes and symptoms.

Why Costello Syndrome Matters in Cancer Care

Because the HRAS gene mutation causes cells to grow abnormally, people with Costello syndrome have an increased risk of developing certain tumors. These include noncancerous wart-like growths called papillomas, often found around the nose, mouth, or anus. More importantly, they have a higher chance of developing cancers such as rhabdomyosarcoma, a soft tissue cancer, and neuroblastoma, a cancer of immature nerve cells. Understanding this risk helps doctors monitor for tumors early and guide care to catch and treat cancers promptly if they occur.

What Patients and Caregivers Might See or Hear

If Costello syndrome is mentioned in medical records, test results, or treatment discussions, it may be in relation to genetic testing or cancer risk. Genetic tests can identify HRAS mutations in children suspected of having the syndrome. Doctors may discuss the need for regular check-ups to watch for tumors or heart problems. Families might also hear about related conditions called RASopathies, which share some features with Costello syndrome. Because it is rare, with only a few hundred cases reported worldwide, families may find limited information and should ask their care team for personalized explanations.

How Doctors Use the Term in Diagnosis and Care

Doctors diagnose Costello syndrome primarily through genetic testing, including full genome or exome sequencing, to find mutations in the HRAS gene. Clinical signs like growth delays, distinctive facial features, and heart issues support the diagnosis. Because the syndrome increases cancer risk, doctors may recommend regular monitoring for tumors starting in early childhood. Testing for HRAS mutations in tumors can also help identify Costello syndrome in children. Treatment focuses on managing symptoms and monitoring for complications rather than curing the genetic condition itself.

Common Confusions and What Costello Syndrome Does Not Mean

Seeing the term Costello syndrome does not mean a person has cancer, only that they have a higher risk of certain tumors. It is not a cancer diagnosis by itself. Also, not all tumors in people with Costello syndrome are cancerous. The syndrome is different from other genetic conditions that may sound similar, so it is important not to assume all features or risks apply to every person. Because HRAS mutations can also appear in tumors of people without Costello syndrome, the context of the mutation matters greatly.

Questions to Ask Your Care Team

If Costello syndrome comes up in your or your child’s care, consider asking: What does this diagnosis mean for our health and cancer risk? What tests or monitoring should we expect? How can we watch for early signs of tumors or other complications? Are there treatments to manage symptoms or reduce risks? How does this affect growth, development, and daily life? Where can we find support and reliable information?

Reading Costello Syndrome in Context

Because Costello syndrome involves complex genetic and medical issues, it is important to understand it as part of a broader health picture. Always ask how it applies to the specific medical report, test result, or treatment plan you are reviewing. Avoid making assumptions based on the term alone. Your healthcare team can explain what it means for your or your child’s unique situation.

Safety and Next Steps

This information is educational and not a substitute for medical advice. If you encounter the term Costello syndrome in medical documents or discussions, the best next step is to talk with your healthcare providers. They can help interpret what it means for you or your child and guide appropriate care, monitoring, and support. Understanding this rare condition can help families feel more informed and prepared to manage health challenges together.