Abstract
Objective
Urinary tract endometriosis affects 0.3–12 % of all cases of endometriosis. Medications have limited efficacy in treating advanced disease. Serous cystadenofibroma is a rare benign variant of ovarian epithelial tumors comprising both epithelial and fibrous stromal components. Its diagnosis is challenging due to its visual resemblance to malignancy.
Case report
A patient diagnosed with ureteral endometriosis underwent surgical excision of the right kidney and ureter. Ten years later, the patient developed a tumor suspected to be malignant at the same site. Following exploratory laparotomy, the tumor was pathologically diagnosed as resembling serous cystadenofibroma.
Conclusion
Differentiating a such tumors from other malignancies based solely on imaging findings is challenging. It is crucial to judge the degree of surgical intervention through intraoperative macroscopic examination and rapid pathological assessment. The efficacy of gonadotropin-releasing hormone analog (GnRHa) and dienogest (DNG) therapy in preventing the recurrence of such tumors following surgery for endometriosis remains uncertain.
Introduction
Urinary tract endometriosis reportedly affects 0.3–12 % of all endometriosis cases [ ]. Medical and surgical therapy options are available; however, in cases of advanced disease, the efficacy of medication is limited, and renal function is likely to be compromised [ ]. Serous cystadenofibroma is a rare benign variant of ovarian epithelial tumors characterized by epithelial and fibrous stromal components. Its diagnosis is often challenging due to its visual resemblance to malignant tumors [ ].
We present a case of a serous cystadenofibroma-like tumor that developed at the site of previous ureteral endometriosis, which had been treated with excision of the right kidney and ureter. We describe the diagnosis and treatment of this case, as to the best of our knowledge, there are no reports in the literature of this tumor arising in the context of ureteral endometriosis.
Case presentation
At the age of 31, the patient in this case, without any history of pregnancy, developed right ureteral stenosis and hydronephrosis following persistent fever. Although urinary tract endometriosis was suspected, right kidney function was relatively preserved. The patient was undergoing treatment for infertility, and her progress was carefully monitored. At the age of 37, the patient developed right renal dysfunction due to stenosis caused by tissue mass growth at the right ureteropelvic junction. Enlargement was observed in the surrounding lymph nodes. The right kidney and ureter were surgically removed for treatment and pathological diagnosis. However, the lesions were tightly adherent, making complete removal challenging, resulting in residual lesions. The pathological diagnosis was consistent with endometriosis with no malignant findings. The residual lesions of ectopic endometriosis later caused venous thrombosis due to central venous occlusion. Therefore, pseudomenopausal and luteal therapy with dienogest was continued until menopause.
Magnetic resonance imaging (MRI) performed 10 years after the initial surgery revealed a new multicentric mural nodule with diffusion-weighted imaging restriction arising from the same surgical site ( Fig. 1 ); thus, exploratory laparotomy was performed.
The tumor, likely originating in the tissues near the right common iliac bone, had spread to the internal and external iliac blood vessels. Images showed extensive neovascularization just beneath the tumor’s surface (serosa). The tumor surface was smooth macroscopically, and no disseminated lesions or atypical blood vessels were observed. Three lesions measuring 10 × 10 mm were biopsied, and rapid pathological diagnosis revealed no malignancy ( Fig. 2 ). The intraoperative cytodiagnosis of ascites was classified as class III with no malignant findings. The pathological finding revealed a simple cyst characterized by an atrophic area, a small cyst enclosed in a short epithelium with mild atypia, and a vascular-rich stroma. Immunostaining of the biopsy specimens revealed that both the epithelium and stroma were positive for Estrogen Receptor (ER). The stroma also showed positivity for Cluster of Differentiation 10 (CD10) and weak positivity for Wilms’ Tumor 1 (WT1). The epithelial component was also positive for Pan-Cytokeratin AE-1/AE-3 (AE1/AE3). Biopsies were negative for napsin A, calretinin, and Forkhead Box Protein L2 (FOXL2). The pathological findings of the stromal intima differed from those typical of a serous cystadenofibroma. Therefore, the tumor was diagnosed as a serous cystadenofibroma-like tumor ( Fig. 3 ). The postoperative course was uneventful, and the patient was discharged from the hospital on the 7th postoperative day. Progestin therapy was continued, and no tumor progression was observed at the 1-year follow-up ( Fig. 4 ).
