Diarrhea Concealing a Duodenal-Cecal Fistula Secondary to Appendiceal Mucinous Neoplasm

Abstract

Primary mucinous adenocarcinoma of the appendix is a rare gastrointestinal malignancy. Fistulous tract formation is a complication that is cited in literature. An 85-year-old man with multiple comorbidities presented with several weeks of persistent non-bloody diarrhea. Laboratory work-up was non-diagnostic. Abdominal imaging with barium contrast showed an enterocolonic fistulous tract extending from the duodenum to the cecum involving an enlarged appendiceal mass. Subsequent biopsy confirmed mucinous appendiceal neoplasm with peritoneal spread to the liver and mesentery. This is the first report describing an enterocolonic fistula formation resulting from this malignancy.

Fistulae involving the appendix: a systematic review of the literature

“…[103][104][105][106][107] Appendiceal fistulae to the GI tract included 10 cases to the sigmoid colon alone, [108][109][110][111][112][113][114][115][116][117] with an additional two concurrently fistulating to the bladder. 118,119 There were 21 cases of fistula to the ileum, 84,[120][121][122][123][124][125][126][127][128] two to the jejunum, 84,129 six to the duodenum, 84,[130][131][132][133] eight to the caecum, 84,[133][134][135][136][137][138] three to the ascending colon, 48,139,140 one to the transverse colon, 141 one to the rectum, 142 and one to a gastrojejunal anastomosis from prior gastroenterostomy. 143 In three cases, fistulae invol...…”

“…Appendiceal fistulae to the GI tract included 10 cases to the sigmoid colon alone, with an additional two concurrently fistulating to the bladder . There were 21 cases of fistula to the ileum, two to the jejunum, six to the duodenum, eight to the caecum, three to the ascending colon, one to the transverse colon, one to the rectum, and one to a gastrojejunal anastomosis from prior gastroenterostomy . In three cases, fistulae involved Meckel's diverticula …”

“…Appendiceal fistulae projecting to the small bowel have been found to communicate with the ileum, 84,[120][121][122][123][124][125][126][127][128] jejunum, 84,129 and duodenum. 84,[130][131][132][133] As expected, fistulae between the appendix and the ileum are most common due to their close proximity, with the first case reported by Volz in 1846. 84 Seldom are fistulae to the jejunum and duodenum encountered.…”

“…Fistulae involving the duodenum have varied causes including appendicitis, adenocarcinoma, endometriosis and tuberculosis. 84,130,131 Large bowel Fistulae between the appendix and the caecum 84,[133][134][135][136][137][138] can be congenital or acquired. A congenital communication between the appendix and the caecum is termed a 'horseshoe appendix', in contradistinction to an acquired fistula.…”

“…Other terms used for appendiceal fistulae include 'faecal fistula', 'cutaneous fistula', 'stercoral fistula', 'sinus', 'sinus tract' and 'cutaneous invasion', 'duodenal-caecal canal' 130 and 'horseshoe appendix'.…”