NF1 and multiple endocrine neoplasia type 2: VHL is the most common genetic cause of pediatric PPGL and tends to present the earliest at an average age of 11-12 years (4, 5, 7, 8, 22), in contrast to those syndromes arising from pathogenic variants in cluster 2 – specifically, MEN-2 (14-20 years) and NF1 (16-17 years); PCC may be the first manifestation of VHL disease (4, 5, 7, 8, 22).