Mucocele of the Appendix
Definition
- A gross or clinical descriptive term for dilation of the appendiceal lumen by mucus
Diagnostic Criteria
- Mucocele is a gross or clinical descriptive term
- It is not a pathologic diagnosis
- Dilation of appendiceal lumen by mucus
- Overt obstruction may or may not be demonstrable
- Most cases due to epithelial proliferations (see individual subjects for details)
- Hyperplastic polyp / mucinous hyperplasia
- Sessile serrated adenoma
- Traditional serrated adenoma
- Mucinous adenoma / cystadenoma
- Mucinous neoplasm with low risk of recurrrence
- Mucinous neoplasm with high risk of recurrence
- Mucinous adenocarcinoma
- Inflammatory, post-inflammatory or obstructive causes uncommon
- May be caused by appendicitis, fecalith, endometriosis
- Usually minimal dilation
- Rarely >2 cm
- Mucosa usually markedly thinned or denuded
- No hyperplasia
- No dysplasia
- Acellular mucin may dissect into or through the wall
- The entire appendix should be examined microscopically
Reference
- Pai RK, Longacre TA. Appendiceal mucinous tumors and pseudomyxoma peritonei: histologic features, diagnostic problems, and proposed classification. Adv Anat Pathol. 2005 Nov;12(6):291-311.
Robert V Rouse MD
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342
Original posting/updates : 10/7/10