61 y.o. male with vague abdominal pain for several weeks.
Lower quadrant abdominal pain, diffuse
Distended appendix with low attenuating fluid/soft tissue.
Follow-up CT delayed one year demonstrates pseudomyxoma peritonei
Mucocele of the Appendix
Mucinous Cystadenoma of the appendix
Mucinous Adenocarinoma of the appendix
Pt. had excision of the appendix which was origally diagnosed on CT as "chronic appendicitis". Pathology results demonstrated that appendix contained a mucinous cystadenocarcinoma. Unfortunately, at the time of surgery there was spillage of the appendiceal contents. Over the course of a year, the patient slowly developed pseudomyxoma peritonei.
The appendix may rarely become distended with sterile mucus. The causes may include simple obstruction by an appendicolith, hyperplasia of the appendix mucosa with overproduction of mucus, a mucinous cystadenocarcinoma of the appendix, or a mucinous adenocarcinoma. A mucocele is found in approximately 0.1% of appendectomies. The patient usually presents with vague abdominal pain, however, approximately 25% are asymptomatic and the mucocele is discovered incidentally at laparoscopy. They appear as oblong, low attenuation masses extending from the cecum. They may occasionally have rim calcification. If a mucinous cystadenocarcinoma ruptures into the abdomen then the patient will develop persistent gelatinous ascites which is extremely difficult to manage. This malignant, gelatinous ascities can displace and/or scallop organs. Chronic cases will develop septations which will often calcify.