The effect of IGF-1 on the closure process of processus vaginalis

BACKGROUND: The processus vaginalis is a peritoneal sac that descends with the testes during the fetal period and typically undergoes obliteration in early life. However, failure of obliteration is associated with pathologies such as inguinal hernia, hydrocele, and cysts of the canal of Nuck, as well as cryptorchidism and epididymal anomalies. The Insulin-like Growth Factor (IGF) system is a signaling pathway that plays a critical role in biological processes such as cell growth, proliferation, and differentiation. This study investigates the effect of IGF-1 on the obliteration process of the processus vaginalis. METHODS: This retrospective study includes 218 cases recorded in the pathology archives between January 1, 2022, and June 30, 2024, comprising cases of inguinal hernia and hydrocele. The inguinal hernia cases include both pediatric and adult age groups, while the hydrocele cases pertain to the pediatric age group. New paraffin blocks were prepared from archived specimens using the manual microarray method, and the samples were stained with IGF-1 antibody. Evaluations were conducted semi-quantitatively under a light microscope. Data analysis was performed using the Pearson chi-square test, Mann-Whitney U test, and Friedman test. RESULTS: No significant differences were observed between the inguinal hernia and hydrocele groups in terms of epithelial, stromal, and muscle staining levels (P = 0.958, P = 0.669, and P = 0.529, respectively). In the hernia group, a significant difference was identified between epithelial and muscle staining levels, with muscle staining being significantly higher (P = 0.016). No significant differences were noted among epithelial, stromal, and muscle staining levels in the hydrocele group (P = 0.199). CONCLUSION: Our study demonstrates that IGF-1 expression is similar in hernia and hydrocele cases, showing positive expression in vascular and muscle tissues but negative expression in epithelial cells. IGF-1 expression was higher in the pediatric group, suggesting that IGF-1 may be associated with closure defects.