Cite this page: Ehdaivand S. Pseudomyxoma peritonei. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/ovarytumorpseudomyxoma.html. Accessed June 5th, 2023.
Definition / general
- Clinically represents abundant gelatinous pelvic / abdominal mucin or mucinous ascites accompanied by peritoneal lesions with bland to low-grade adenomatous mucinous epithelium intimately associated with pools of extracellular mucin and fibrosis
- Peritoneal mucinous tumor / ascites almost always has mucinous epithelium present, if adequately sampled
- Rare cases lacking mucinous epithelium usually do not recur
- Virtually all cases have appendiceal, not ovarian origin
- Three types of pseudomyxoma peritonei:
- Superficial; mucin contains hyperemic organizing vessels and fibroblasts
- Dissecting with fibrosis
- Metastatic mucinous carcinoma
- Mucin is associated with cystic epithelial implants on peritoneal surfaces, adhesions to bowel, abdominal wall and bladder; intestinal obstruction and peritonitis
- Due to production of MUC2, a gel-forming mucin that forms strong bonds with stroma
- Surgical pathology report:
- Pseduomyxoma peritonei is NOT a pathologic diagnosis (Am J Surg Pathol 2000;24:1447)
- Include whether mucin contains benign, borderline or malignant epithelium, plus whether mucin dissects into tissues forming a fibrous reaction
- Benign or borderline epithelium should be diagnosed pathologically as disseminated peritoneal adenomucinosis
- Malignant epithelium should be called disseminated peritoneal carcinomatosis
Treatment
- Excise as much tumor as possible, plus chemotherapy
Microscopic (histologic) images
AFIP images
Large pools of acellular mucin
Mucin spillage
Dissecting mucin with fibrosis in omentum
