Although it would have been almost impossible to make the right diagnosis prior to the operation in this case, there are still many aspects that are worth reflecting on. First, the patient came into the emergency room with signs and symptoms of acute mechanical intestinal obstruction, and he had no previous abdominal surgery. Therefore, we almost could exclude the diagnosis of adhesive intestinal obstruction. The differential diagnosis at initial presentation included a colonic tumor, benign or malignant small intestinal tumors, and a stricture secondary to other conditions (e.g., enterocele, volvulus, intussusception, and so on), all of which often required an operation. Second, when we take the medical history of a patient with an unexplained intestinal obstruction, we should be more careful with the patient's past medical history and potential causes of the symptoms, these may help us make right diagnosis. In this case, we reinquiry the patient's case history on postoperative day, the patient had had a right lower quadrant abdominal intermittent slight chronic pain symptoms in the past 20 years, but there was no other influence in his work and daily life, so he did not care about the symptoms at all. Now if we integrated the medical history and CT, it seemed that we may have made the right diagnosis before operation. Third, we support the clinical application of total abdomen CT scanning in the case of an unexplained mechanism of abdominal obstruction. An abdominal CT is a rapid, simple, and effective means for diagnosing the location, cause, and degree of obstruction in cases of unexplained intestinal obstructions. It is particularly useful for orienting the clinician to the location of obstruction, and it would help surgeons decide where to make an incision, as an appropriately placed incision is crucial to the success of an operation.
So how did we determine the extent of surgery for the patient with appendiceal mucocele? It is vital to discriminate benign and malignant appendiceal mucocele in determining the extent of surgery. Appendectomy is appropriate therapy for unruptured benign appendiceal mucoceles, like this case. When benign appendiceal mucocele protrudes into cecal lumen, partial cecectomy may be curative. “If either cecal wall or ileum is invaded by tumor or adequate surgical margins cannot be secured, ileocecal section or right hemicolectomy may be required.” If malignancy cannot be exclusive, right hemicolectomy should be considered.[1,18] In this case, we should exclude the possibility of the intestine necrosis; otherwise, we must resect the highly suspected necrotic intestinal tissue further. The key-point of surgical treatment is to make resection margin clear and keep the appendiceal mucocele intact. The prognosis for benign appendiceal mucocele following complete ablation is excellent and the 5-year survival rate is almost 100%. A patient with malignant mucocele, however, is much poorer, and the 5-year survival rate has association with the degree of extension of the tumor and varies between 30% and 80%.
. Stocchi L, Wolff BG, Larson DR, et al. Surgical treatment of appendiceal mucocele. Arch Surg 2003;138:585–9.
. Ruiz-Tovar J, Teruel DG, Castiñeiras VM, et al. Mucocele of the appendix. World J Surg 2007;31:542–8.
. Garcia Lozano A, Vazquez Tarrago A, Castro Garcia C, et al. Mucocele of the appendix: presentation of 31 cases. Cir Esp 2010;87:108–12.
. Calişkan K, Yildirim S, Bal N, et al. Mucinous cystadenoma
of the appendix: a rare cause of acute abdomen. Ulus Travma Acil Cerrahi Derg 2008;14:303–7.
. Louis TH, Felter DF. Mucocele of the appendix. Proc Bayl Univ Med Cent 2014;27:33–4.
. Opreanu RC, Sobinsky J, Basson MD. Appendicitis and benign appendiceal mucocele presenting as large bowel obstruction. J Gastrointest Surg 2013;17:609–10.
. Pickhardt PJ, Levy AD, Rohrmann CA Jr, et al. Primary neoplasms of the appendix: radiologic spectrum of disease with pathologic correlation. RadioGraphics 2003;23:645–62.
. Pickhardt PJ, Levy AD, Rohrmann CA, et al. Primary neoplasms of the appendix manifesting as acute appendicitis: CT findings with pathologic comparison. Radiology 2002;224:775–81.
. Carr NJ, McCarthy WF, Sobin LH. Epithelial noncarcinoid tumors and tumor-like lesions of the appendix: a clinicopathoogic study of 184 patients with a multivariate analysis of prognostic factors. Cancer 1995;75:757–68.
. Lee J, Lim HK, Lee SJ. Ureteral obstruction caused by mucocele of the appendix: MDCT findings. Australas Radiol 2007;51:59–61.
. Kim SH, Lim HK, Lee WJ, et al. Mucocele of the appendix: ultrasonographic and CT findings. Abdom Imaging 1998;23:292–6.
. Pickhardt PJ, Levy AD, Rohrmann CA Jr, et al. Primary neoplasms of the appendix: radiologic spectrum of disease with pathologic correlation. Radiographics 2003;23:645–62.
. Papaziogas B, Koutelidakis I, Tsiaousis P, et al. Appendiceal mucocele. A retrospective analysis of 19 cases. J Gastrointest Cancer 2007;38:141–7.
. Garg PK, Prasad D, Aggarwal S, et al. Acute intestinal obstruction
: an unusual complication of mucocele of appendix. Eur Rev Med Pharmacol Sci 2011;15:99–102.
. Mourad FH, Hussein M, Bahlawan M, et al. Intestinal obstruction
secondary to appendiceal mucocele. Dig Dis Sci 1999;44:1594–9.
. Shang J, Ruan LT, Dang Y, et al. Contrast-enhanced ultrasound improves accurate identification of appendiceal mucinous adenocarcinoma in an old patient: a case report. Medicine (Baltimore) 2016;95:e4637.
. Kammori M, Mafune K, Hirashima T, et al. Forty-three cases of obturator hernia. Am J Surg 2004;187:549–52.
. Park KJ, Choi HJ, Kim SH. Laparoscopic approach to mucocele of appendiceal mucinous cystadenoma
: feasibility and short-termoutcomes in 24 consecutive cases. Surg Endosc 2015;29:3179–83.
. Weber G, Teriitehau C, Goudard Y, et al. Mucocèle appendiculaire. Feuillets Radiol 2009;49:40–4.