Mature cystic teratoma mimicking a tailgut cyst in an adolescent female: a case report.

Presacral tumors are uncommon, particularly in the pediatric population, and can arise from various germ cell types during embryologic development. Tailgut cysts, or retrorectal cystic hamartomas, represent rare congenital anomalies resulting from defective regression of hindgut remnants. We present a unique case of a 13-year-old female with pelvic symptoms, initially suspected to have a tailgut cyst based on imaging findings. However, surgical exploration revealed a mature cystic teratoma, a rare occurrence in this age group. Surgical excision was performed using an anterior approach, revealing adhesions and necessitating meticulous dissection for complete removal. Histopathological examination of the mass unexpectedly confirmed a mature cystic teratoma, characterized by a fibrovascular cyst wall containing smooth muscle and lobules resembling salivary acini, the cyst's surface exhibited squamous and respiratory-type epithelium. The accurate diagnosis of presacral masses, rather than relying solely on diagnostic measures, underscores the importance of prioritizing surgical exploration for definitive assessment and management.