Pseudomyxoma peritonei has been caused by rupture of a mucinous neoplasm of the appendix. There can be varying degrees of neoplasia: low grade appendiceal mucinous neoplasm, high-grade appendiceal mucinous neoplasm, and mucinous adenocarcinoma. While liver scalloping is not a major feature in this case, the diagnosis of pseudomyxoma can be made based on the presence of intermediate attenuation mucin-containing ascites and identification of an appendiceal primary tumor. 

In this case, a higher grade tumor is favored due to invasion of the small bowel resulting in malignant small bowel obstruction, although evaluation of the primary tumor is needed for definitive histological classification.  

The few flecks of calcification can provide a hint of the location of the primary tumor (calcification is a typical feature of mucinous neoplasms), which at first can be challenging to differentiate from small bowel loops. Interestingly, the delayed images help to outline the appendiceal contours and show discontinuity of the tip, indicating rupture.