UCLA Radiological Sciences Proceedings

PIK3CA-related overgrowth syndrome (PROS) is characterized by a range of mutations in the phosphoinositide 3-kinase (PI3K) pathway, resulting in diverse and variable imaging findings. Hyperplasia in PROS can affect multiple organ systems and commonly presents with asymmetric limb and brain enlargement, venous anomalies, and pigmented nevi. While genetic testing for PROS may be considered in the presence of these features, diagnosis and treatment are often delayed in patients with atypical phenotypes or those without visible external anomalies. We report a case of newly diagnosed PROS in a 20-year-old woman with a lifelong history of abdominal pain. This patient exhibited no external signs of the disease and had unusual vascular manifestations identified through imaging. The unique clinical and imaging features in this case provide valuable insight into the broad spectrum of PROS findings and offer guidance for radiologists in recognizing these elements.