Pseudomyxoma retroperitonei with spontaneous skin fistula.

We describe the imaging features in a patient with pseudomyxoma retroperitonei arising from a mucinous carcinoma of the appendix with spontaneous development of a skin fistula. The thick wall and septa characteristic of pseudomyxoma were best demonstrated on gadolinium-enhanced magnetic resonance imaging. This patient illustrates (a) the potential of pseudomyxoma to cause skin fistula and (b) the possibility that this intraabdominal process can first present as a dermatologic complication.