TITLE:
Primary Retroperitoneal Mature Cystic Teratoma with Incidental Extramedullary Hematopoiesis in a 35-Year-Old Female
AUTHORS:
Gaber Elsafy, Alaa Aly Mousa, Moustafa Ismail, Abdullah Elrashidy
KEYWORDS:
Teratoma, Retroperitoneal, Extramedullary, Benign
JOURNAL NAME:
Open Journal of Urology,
Vol.16 No.7,
July
31,
2026
ABSTRACT: Primary retroperitoneal teratomas are rare germ cell tumors in adults. The presence of extramedullary hematopoiesis (EMH) within a benign mature cystic teratoma is an exceptionally scarce histopathological variant. We report the case of a 35-year-old female who presented with a large, well-defined retroperitoneal mass. Following successful complete surgical excision, histopathological examination revealed classic elements of a mature cystic teratoma interspersed with ectopic bone elements and foci of extramedullary hematopoiesis. The patient experienced an uneventful recovery with no signs of recurrence. This case emphasizes the diagnostic importance of comprehensive tissue sampling to rule out malignancy and identify unique benign tissue variations.