Ileocolic intussusception due to mucocoele of the appendix causing small bowel obstruction
Presentation
One week generalized colicky abdominal pain and vomiting
Patient Data
Abdomen and pelvis
There is a 14 cm complex ileocolic and ileoileal intussusception. A tubular blind-ending structure is visualized within the intussusception, with a 3.5 cm, murally calcified cyst at its base. The mid and distal small bowel proximal to the intussusception is dilated measuring up to 3.7 cm.
Small volume ascites. Note of an incidental small simple liver cyst.
Case Discussion
The intussusception was able to be reduced at surgery and the patient underwent an uncomplicated right hemicolectomy.
Histology:
Sections of the appendix wall show a lumen filled with partly calcified mucus. The wall is generally thinned and composed of dense collagenous tissue and in many places lacks an epithelial lining. However, in areas, the lumen is lined by a single layer of columnar mucus secreting epithelium with mild atypia of the basally located nuclei. Occasional thin papillary projections are present. The epithelium rests directly on the fibrous wall. There is no high grade dysplasia or invasive malignancy. No mucus is seen dissecting through the appendix wall.
No malignancy in nodes.
FINAL DIAGNOSIS: Low grade appendiceal mucinous neoplasm.
Case also contributed by Dr. Shyam Sankaran