Multiplex immunohistochemistry reveals histological features of three different intestinal polyp subtypes in pediatric patients.

BACKGROUND: Histologically, our understanding of intestinal polyps remains limited in scope, particularly regarding the diverse subtypes observed in pediatric patients. To enhance our comprehension, three different polyp subtypes including solitary juvenile polyps (SJPs), juvenile polyposis syndrome (JPS)-related polyps, and Peutz‒Jeghers syndrome (PJS)-related polyps were investigated. METHODS: This study used advanced multiplex immunohistochemistry (mIHC) technology to analyze polyps comprising 4 SJP, 4 JPS and 4 PJS polyps from 12 individual patients who underwent colonoscopies or radical surgical procedures. subtypes. RESULTS: These mIHC analyses revealed some differences among these polyp subtypes. PJS-related polyps, specifically, displayed epithelial dysplasia with dendritic gland hyperplasia and distinct villous structures adorned with finger-like projections on their surfaces. In contrast, SJP and JPS polyps exhibited cystic glandular dilation, with their surfaces lined with continuous but eroded epithelia. Furthermore, PJS polyps had an abundance of microvessels and thick smooth muscle fibers, whereas SJP and JPS polyps were characterized by lymphoid follicle-like structures. CONCLUSIONS: These findings not only deepen our structural understanding of various intestinal polyp subtypes but also offer valuable insights that may inform the diagnosis of patients with these conditions.