Pseudomyxoma extraperitonei: a lethal complication of mucinous adenocarcinoma of the appendix.

We report the unusual case of a 56-yr-old man who presented with an appendix abscess. This abscess failed to respond to standard treatment, and recurred despite operative intervention. A colocutaneous fistula developed, which initially discharged frank pus, then began discharging mucus via two cutaneous sinuses. No evidence of malignancy was detected from either repeat curettings or a diagnostic laparotomy. One and a half years after the initial presentation, histologic examination finally revealed mucinous adenocarcinoma of the appendix. We postulate that this malignancy in a retrocecal appendix resulted in a mucocele, which ruptured into the retroperitoneal space and drained via cutaneous sinuses, so-called pseudomyxoma extraperitonei. The patient declined further surgical intervention, and despite initial control by radiotherapy, the tumor spread locally to involve the entire right lower quadrant of the abdomen. The patient eventually died 39 months after the initial presentation.