Presentation
Few weeks history of right lower abdominal pain. The abdominal ultrasound revealed a ruptured right ovarian mass (according to the ultrasound report). A pelvic MRI was requested.
Patient Data
Well-defined tubular cystic structure in the right pelvic region, contiguous to the base of the cecum well-visualized on sagittal T2 sequences with a focal defect of its posteromedial wall (14 mm) well-visualized on axial and coronal T2 sequences. It shows a low signal on TI, a high signal on T2 with thickened irregular enhancing inner wall as well as enhancing mural nodules which show restricted diffusion.
Moderate ascites with thickening and enhancement of the peritoneal reflections.
Both ovaries are well-visualized, atrophied.
Fluid-filled tubular structure of the right pelvic region with curvilinear mural calcification as well as irregular wall thickening with enhancing mural nodularity. The focal mural defect is well-visualized on contrast-enhanced images. Moderate surrounding ascites and in the pelvic region with irregular thickening of the peritoneal reflections and greater omentum.
No mediastinal, abdominal, or pelvic lymphadenopathy.
Single gallstone (10 mm) is noted.
Arteria lusoria (incidental finding).
Both lungs are clear.
Annotated images:
- mural calcification (blue arrow)
- focal wall defect of the appendiceal mucocele (green arrow)
- appendiceal mucocele (yellow arrow)
- appendiceal tip (red arrow)
Thick gelatinous fluid from the ascites during surgery (rich in mucin on cytology exam).
Case Discussion
CT and MRI features most consistent of ruptured appendiceal mucocele of malignant origin with pseudomyxoma peritonei.
The patient went to have a right hemicolectomy, omentectomy, extended colpohysterectomy with intraoperative chemotherapy. The histopathological examination revealed mucinous adenocarcinoma of the appendix with pseudomyxoma peritonei.
Additional contributors: ZE. Boudiaf, MD, S. Zine, MD.