Keywords:
Abdominal Viscera, Abdomen, Gastrointestinal tract, CT, Biopsy, Surgery, Inflammation, Neoplasia, Pathology, Retrospective, Cross-sectional study, Performed at one institution
Authors:
K. Khandwala1, N. Sajjad2, W. A. Memon1, A. Malik3; 1Karachi/PK, 2Karachi, Si/PK, 3Atlanta/US
DOI:
10.26044/ecr2020/C-04208
Results
31 patients were included in the study. 10 out of 31 patients presented with diffuse abdominal pain. 9 of the 31 patients presented with symptoms of acute appendicitis and localized right iliac fossa pain, while 4 presented with a palpable abdominal mass. 20 patients underwent simple appendectomy while 11 patients underwent right hemicolectomy. The mean appendiceal diameter was 2.6 cm (1.1-5.4 cm), wall thickness was 2.8 mm (1.1-8.8 mm) and mean attenuation was 28 HU (5-173 HU). Periappendiceal fat stranding showed statistically significant association with inflammatory mucoceles (P-0.01). Wall enhancement was present in 60% of inflammatory mucoceles (P-0.17) Fig. 1.
![](https://epos.myesr.org/posterimage/esr/ecr2020/156609/media/886287?maxheight=300&maxwidth=300)
Fig. 1: Appendiceal mucocele with co-existing appendicitis in a 35-year-old male with right iliac fossa pain. Generalized dilatation of the appendix measuring 17 mm in diameter with wall enhancement and minimal periappendiceal fat stranding (red arrow).
Focal cystic dilatation was present in 15 out of 31 patients while 16 patients had generalized dilatation of the appendix. Out of focal dilatations, 6 were in the region of the base, 5 in the mid part of the appendix and 4 in the tip of the appendix. However none of these showed statistically significant associations with histopathology (P-0.54). Mural calcification, present in 38.7% of cases, achieved statistical significance in predicting benign mucoceles (P-0.003) Fig. 2.
![](https://epos.myesr.org/posterimage/esr/ecr2020/156609/media/886302?maxheight=300&maxwidth=300)
Fig. 2: Appendiceal mucocele in an 83 year old female with vague abdominal pain. Mural calcifications and internal septations were present (red arrow). On pathology, this was a low-grade mucinous neoplasm.
Internal septations were seen in only in benign and malignant mucoceles (P-0.04). Presence of a soft-tissue thickening was seen in 19.4% of cases and this showed statistically significant association with malignant mucoceles (P-0.01) Fig. 3.
![](https://epos.myesr.org/posterimage/esr/ecr2020/156609/media/886308?maxheight=300&maxwidth=300)
Fig. 3: Appendiceal mucocele in a 57 year old male with abdominal distension. Soft tissue thickening was present in the base with significant periappendiceal fat stranding. This proved to be mucinous adenocarcinoma on pathology.
ROC analysis showed best cut-off diameter for diagnosis of inflammatory mucoceles ≤2.2 cm with a sensitivity of 90.0% and specificity of 71.4%, positive predictive value of 60% and negative predictive value of 93.8% Fig. 4.
![](https://epos.myesr.org/posterimage/esr/ecr2020/156609/media/886323?maxheight=300&maxwidth=300)
Fig. 4: ROC curve analysis for inflammatory versus neoplastic mucoceles against diameter.