- Mucinous cystadenomas usually occur in the appendix, ovaries and pancreas. This is the first report to describe mucinous cystadenoma of the ascending colon. A 32-year-old female presented with abdominal pain. Radiographic studies demonstrated a space-occupying lesion in the ascending colon associated with intussusception. Right colectomy revealed a cystic mass within the ascending colon that contained thick mucin and was lined by mucin-producing columnar epithelium. Clinical and pathologic features with a brief review of the literature are presented.