Understanding PIK3CA and PROS

PIK3CA-Related Overgrowth Spectrum, or PROS

What is PROS?

PROS stands for PIK3CA-Related Overgrowth Spectrum.


PROS is the name for a group of conditions that are caused by a mutation in a gene called PIK3CA. The term mutation means the gene isn’t working correctly.

PIK3CA-Related Overgrowth Spectrum
Did you know?

In 2013, researchers proposed grouping abnormal growth, vascular conditions, and lymphatic conditions caused by PIK3CA mutations under the term PROS. By uniting these many different conditions under one new term, researchers hoped to improve diagnosis, help manage symptoms, and establish future clinical trials. The criteria for PROS may change as research develops.


What conditions are PROS conditions?

You may have been diagnosed with PROS or one of the following PROS conditions:



(Klippel-Trenaunay Syndrome)

CLOVES syndrome

(Congenital Lipomatous Overgrowth, Vascular malformations, Epidermal nevi, Scoliosis/skeletal and spinal)


(Isolated Lymphatic Malformation)


(Megalencephaly-Capillary Malformation)


(HemiMegalEncephaly)/DMEG (Dysplastic MEGalencephaly)/Focal cortical dysplasia type II


(HemiHyperplasia-Multiple Lipomatosis)




(Facial Infiltrating Lipomatosis)


(FibroAdipose Vascular Anomaly)


Muscular HH



(FibroAdipose hyperplasia or Overgrowth)

CLAPO syndrome

(Capillary malformation of the lower lip, Lymphatic malformation of the face and neck, Asymmetry of the face and limbs, and Partial or generalized Overgrowth)

Epidermal nevus, benign lichenoid keratosis, or seborrheic keratosis

Other conditions may be identified and characterized as PROS. Talk to your doctor to find out if your condition is a PROS condition.

This website can provide you with important information, guidance, and support as you learn about your PROS condition and either consider or navigate treatment with VIJOICE® (alpelisib) tablets. See how VIJOICE may help.

Kids' Q&A
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What if my child has questions about their PROS condition or VIJOICE?

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To help you explain certain aspects of their treatment journey, you will find tips for talking to your child throughout this website.


How do PIK3CA mutations cause PROS?

Your condition has been diagnosed as a PROS condition because it is caused by PIK3CA mutations. Let’s take a closer look at the role these mutations play in the body.


Image depicting PI3Kα protein as gears

Think of your body as a machine. In the machine, there are gears that are responsible for keeping it running. One of these gears is called the PI3Kα protein, which receives instructions from the PIK3CA gene to help ensure the machine operates correctly. When these gears move at the right speed, the machine can function properly.


Image depicting PI3Kα gears breaking

When a PIK3CA mutation occurs, the instructions cause the PI3Kα protein to move too quickly. As a result, the machine malfunctions, resulting in the signs and features of your PROS condition.

The PI3Kα protein is responsible for ensuring that many different parts of the body work correctly. That’s why each PROS condition, and how it shows up in a person’s body, is different.


While all PROS conditions are different, the role of the PI3Kα protein is the same.

Find out how VIJOICE works.

Kids' Q&A
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Why do I have a PROS condition?

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Before you were born, a change to your DNA randomly occurred inside of your body. This change is called a mutation, and it’s why you have a PROS condition.