PROS, or “PIK3CA-Related Overgrowth Spectrum,” is a group of conditions caused by changes in the PIK3CA gene. This gene plays a role in cell growth and development. A mutation in this gene can cause certain cells to grow too quickly or excessively, leading to tissue and organ overgrowth. The severity and type of overgrowth can vary from person to person, depending on where in the body the mutation has an effect.
