title: Mucinous appendiceal cystadenoma complicated by torsion presenting as a retroperitoneal mass.
mesh_terms: D000368:Aged; D001063:Appendiceal Neoplasms / Q000175:diagnosis*; D003537:Cystadenoma / Q000175:diagnosis*; D003937:Diagnosis, Differential; D006801:Humans; D008297:Male; D009078:Mucocele / Q000175:diagnosis; D012186:Retroperitoneal Neoplasms / Q000175:diagnosis*; D014102:Torsion Abnormality