Infantile Myofibromatosis (IM)
Infantile Myofibromatosis (IM) is a rare genetic condition that causes benign
(non-cancerous) tumors, called myofibromas, to form in the body.
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These tumors are made of fibrous tissue and can appear in the skin, muscle, bone, or internal organs.
Because IM is so rare, many doctors may never encounter it in their careers — which is why families often feel isolated and uncertain after diagnosis. Our goal is to change that by providing clear, trustworthy information in one place.
Types of IM
IM can look different from child to child.
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There are three main forms of Myofibromas- Solitary, Multi-centric, and Generalized (Visceral).
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Solitary - This is when there is only one tumor, usually in the skin, muscle, or bone.
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Multi-centric - IM is multi-centric when multiple tumors are found in different parts of the body,
but usually not involving internal organs.
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Generalized/Visceral - When tumors affect internal organs (like the lungs, liver, or intestines) this is diagnosed as the visceral form of IM. This form can be more serious and may require more aggressive forms of treatment.
What Causes IM?
IM is often linked to genetic mutations in the PDGFRB or NOTCH3 genes.
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These mutations are inherited in an autosomal dominant pattern, meaning a parent carrying the gene has a 50% chance of passing it on to their child.
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Research is still ongoing, but these genetic discoveries are helping doctors understand better treatments.
Diagnosing IM
Because Infantile Myofibromatosis is so rare, diagnosis can sometimes take time and may involve several specialists. IM can appear in different ways depending on where the tumors (myofibromas) form - from small skin nodules, to deeper growths in muscle, bone or internal organs.
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Doctors usually begin by gathering a detailed medical history and performing a physical exam to identify any visible or palpable lumps. From there, imaging and tissue testing are often used top confirm the diagnosis.
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• Physical exams (visible or palpable tumors)
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• Imaging (like ultrasounds, MRIs, or CT scans)
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• Biopsy (to confirm the tumor type under a microscope)
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• Genetic testing (to check for PDGFRB or NOTCH3 mutations)
Treatment Options
Watch and Wait
Remarkably, many IM cases resolve on their own over time. These cases use a 'Watch & Wait' approach in which a team of doctors and or specialists may monitor the child monthly/yearly to access tumor growth.
Surgery
Sometimes surgery is needed to remove tumors if tumors interfere with function or cause pain.
Targeted Therapy
Immunotherapy medications like Imatinib have shown effectiveness in some cases with PDGFRB mutations.
Chemotherapy
Chemotherapy may be used for cases with severe visceral involvement.