Mapping the PIK3CA-related overgrowth spectrum (PROS) patient and caregiver journey using a patient-centered approach.

Background: PROS disorders are driven by somatic, gain-of-function mutations in PIK3CA that result in hyperactivation of the phosphatidylinositol-3-kinase (PI3K) signaling pathway. PROS encompasses a broad spectrum of overlapping phenotypes (including overgrowth and vascular malformations) that vary significantly in their severity; every case is unique, leading to different, complex experiences. Here, we aim to describe the PROS experience from the patients' and caregivers' points of view, from onset to diagnosis to treatment and support.