melanosis peritonei

Melanosis peritonei is extremely rare, and only rare cases have been reported in the English literature, four in association with ovarian dermoid cysts, and one with a peritoneal cyst.

Melanophages are present focally in the submucosa, superficial muscle layer, and ulcer bases of the cyst and extensively as small nodules on the peritoneal surface and in the omentum.

The tendency of perivascular nodular aggregation of melanophages favors a hematogenous (or lymphatic) spread rather than implantation.

The melanin can originate from the esophageal-like squamous mucosa of the cyst.

Associations

 enteric duplication cyst (8554107)

References

 Melanosis peritonei associated with enteric duplication cyst. A case report. Jung YC, Chen CJ, Tzeng CC. Am J Surg Pathol. 1996 Feb;20(2):181-6. PMID: 8554107