Retroperitoneal Mucinous Cystadenocarcinoma

Abstract

Introduction: Primary retroperitoneal mucinous cystadenocarcinomas (RMC) are rare tumors characterized by mucinous epithelium and ovarian stroma. Their low prevalence complicates the establishment of their etiology, pathogenesis, and behavior. We present a new case of RMC.

Clinical Case:  A 32-year-old woman with no relevant medical history presented with abdominal pain and a palpable mass in the right iliac fossa. A CT/MRI scan revealed a 7.5 cm complex cystic mass in the right retroperitoneum, featuring solid formations and in contact with the psoas muscle. Surgery was performed, resulting in the complete resection of the lesion, including partial resection of the psoas muscle and the sciatic nerve. Histological analysis confirmed a poorly differentiated RMC with ovarian stroma, and positivity for PAX8 suggested a Müllerian origin. Five months post-surgery, the patient experienced a recurrence of pelvic pain, and a single iliac lymph node metastasis was identified, prompting the initiation of chemotherapy. Unfortunately, the patient passed away seven months after the surgery.

Conclusion: RMC are rare tumors that necessitate a complex diagnostic approach and multidisciplinary management. Surgery remains the primary treatment, while chemotherapy is considered in selected cases.