case_images: PMC6535882_01
case_images: T2-weighed magnetic resonance imaging at 9 (a, b) and 32 (c, d) weeks of gestation. (a) Bilateral pelvic masses with a horizontal view. A right-sided multilocular mass (arrow) and left-sided unilocular mass (asterisk) are shown. We suspected bilateral ovarian tumors at this point. (b) Sagittal view. The left-sided unilocular mass (asterisk) is shown. (c) Horizontal view. The right-sided multilocular mass (arrow) is involved in or at least is located very close to the large mass (star). (d) Sagittal view. The left-sided mass (star) occupies the pelvic cavity.
case_images: CRIOG2019-3120921.001.jpg
case_images: PMC6535882_01_CRIOG2019-3120921.001.jpg
case_images: fig1
case_images: Transvaginal ultrasound and magnetic resonance imaging (MRI) (Figures 1(a) and 1(b)) revealed two pelvic cysts. At 32 weeks of gestation, MRI revealed that the left-sided cyst size had increased to 27 cm in diameter (Figures 1(c) and 1(d)), although she was asymptomatic. As shown in Figure 1(c), the right-sided multilocular cyst became very close to the left monocytic cyst.
case_images: Intra-operative findings during cesarean section (CS) and tumor resection at 37 weeks of gestation. (a) The large cyst (arrow) is on the dorsal and caudal sides of the uterus (star) following CS. (b) The large cyst wall (arrow) is adjacent to the right multicystic ovarian tumor (arrowhead). We resected the right adnexa and a part of the cyst wall. The wall of the large cyst was coarse and weak, suggestive of degeneration. Uterus (double arrows).
case_images: CRIOG2019-3120921.002.jpg
case_images: PMC6535882_01_CRIOG2019-3120921.002.jpg
case_images: fig2
case_images: We resected it as widely as possible together with right salpingo-oophorectomy (Figures 2(a) and 2(b)).
case_images: Histological findings of the right ovarian tumor (a-d). (a) The epithelium of the right ovarian tumor without dysplasia contains mucin. It is consistent with mucinous cystadenoma (Hematoxylin and Eosin stain, x20). (b) The large cyst wall containing serous fluid shows partial defects of epithelium. This is due to adhesion of the abdominal cavity and cyst. (c-e) The large cyst wall is strongly positive, partly weakly positive (arrows), and partly positive (arrowheads) for cytokeratin AE1/AE3, estrogen receptors (ER), and progesterone receptors (PR), respectively (x20).
case_images: CRIOG2019-3120921.003.jpg
case_images: PMC6535882_01_CRIOG2019-3120921.003.jpg
case_images: fig3
case_images: The resected tumor consisted of a large unilocular cyst with serous fluid and a mucinous cystadenoma (Figures 3(a) and 3(c)). In the former, lining epithelium was absent in many parts (Figure 3(b)) and mucinous epithelium was occasionally found in continuity with the cyst wall of the latter (right ovarian cystadenoma). Immunohistochemistry revealed focally positive staining for estrogen and progesterone receptors on the resected cyst wall (Figures 3(d) and 3(e)).