Appendiceal mucocele is a very rare clinical condition. Associated ascites and an ovarian mass could suggest synchronous ovarian cystadenocarcinoma with pseudomyxoma peritonei. We describe the case of a 36-year-old female with a mucinous cystadenoma of the appendix causing intussusception, diagnosed by CT but not by US scan, since the associated anomalous fixation of the caecum was misleading i...