IMAGES FOR SURGEONS ANZJSurg.com
Appendiceal mucocele: the importance of getting a preoperative diagnosis
An 84-year-old woman presented with an abdomen swollen at the right lower quadrant where a mass was palpated. Abdominal computed tomography (CT) scan showed a giant round lesion measuring 9 cm × 4 cm in diameter in continuity with the caecum (Fig. 1). A preoperative diagnosis of appendiceal mucocele (AM) was attained and the patient was submitted to open appendicectomy (Fig. 2). The final diagnosis was mucinous cystadenoma of the appendix. After 4 months of follow-up, there is no evidence of recurrence. AM is a rare disease, found in only 0.4% of all appendectomied specimens.1 Achieving a preoperative diagnosis is of paramount importance because it permits choosing the most appropriate surgical technique.1 The algorithm for the selection of the type of surgery was provided by Dhage-Ivatury and Sugarbaker in 2006: in brief, laparotomy should be preferred over laparoscopy and the more locally advanced the disease is, the more invasive the resection should be.2 During the intervention, in fact, every possible effort must be attempted to keep the cystic lesion intact, avoiding the rupture or inadvertent spillage of the mucoid material into the peritoneal cavity: such complications, in fact, lead to the development of pseudomyxoma peritonei, a condition encumbered by a far worse prognosis than the one associated with AM. CT is recognized as the most proper imaging tool for the preoperative diagnosis of AM.3 Classically, it shows a cystic dilatation of the appendix lumen ranging from 1 to 14 cm in size where wall
calcifications are frequent.3 CT also permits the differential diagnosis with other lesions localized in the right lower quadrant of the abdomen, such as common appendicitis, mesenteric, duplication and urachal cysts, lymphangioma, abscess and haematoma.3 A further advantage of this imaging modality was furnished in 2013 by Wang and colleagues who tested its utility for differentiating preoperatively malignant from benign forms of AM: of interest, the presence of wall irregularity and soft-tissue thickening resulted to indicate a malignant pattern of AM.4 Although there is a need for more works, their results, if corroborated, could represent a valid preoperative guide, helping the surgeons act the best operative tactics for the patients with benign or malignant AM.
References 1. Rampone B, Roviello F, Marrelli D, Pinto E. Giant appendiceal mucocele: report of a case and brief review. World J. Gastroenterol. 2005; 11: 4761–3. 2. Dhage-Ivatury S, Sugarbaker PH. Update on the surgical approach to mucocele of the appendix. J. Am. Coll. Surg. 2006; 202: 680–4. 3. Demetrashvili Z, Chkhaidze M, Khutsishvili K et al. Mucocele of the appendix: case report and review of literature. Int. Surg. 2012; 97: 266–9. 4. Wang H, Chen YQ, Wei R et al. Appendiceal mucocele: a diagnostic dilemma in differentiating malignant from benign lesions with CT. AJR Am. J. Roentgenol. 2013; 201: W590–5.
Fig. 1. Abdominal computed tomography scan showing a giant appendiceal mucocele of 9 cm × 4 cm in size (red arrow) with mixed content (air-fluid and hyperdense material) and wall calcifications (a: axial view; b: sagittal view).
© 2015 Royal Australasian College of Surgeons
ANZ J Surg •• (2015) ••–••
2
Images for surgeons
Edoardo Virgilio, MD Anna Tallerini, MD Paola Addario Chieco, MD Giorgio Castagnola, MD Marco Cavallini, MD Medical and Surgical Sciences and Translational Medicine, Faculty of Medicine and Psychology ‘Sapienza’, St. Andrea Hospital, Rome, Italy doi: 10.1111/ans.13159
Fig. 2. Intraoperative view of the giant appendiceal mucocele.
© 2015 Royal Australasian College of Surgeons
Appendiceal mucocele: the importance of getting a preoperative diagnosis
An 84-year-old woman presented with an abdomen swollen at the right lower quadrant where a mass was palpated. Abdominal computed tomography (CT) scan showed a giant round lesion measuring 9 cm × 4 cm in diameter in continuity with the caecum (Fig. 1). A preoperative diagnosis of appendiceal mucocele (AM) was attained and the patient was submitted to open appendicectomy (Fig. 2). The final diagnosis was mucinous cystadenoma of the appendix. After 4 months of follow-up, there is no evidence of recurrence. AM is a rare disease, found in only 0.4% of all appendectomied specimens.1 Achieving a preoperative diagnosis is of paramount importance because it permits choosing the most appropriate surgical technique.1 The algorithm for the selection of the type of surgery was provided by Dhage-Ivatury and Sugarbaker in 2006: in brief, laparotomy should be preferred over laparoscopy and the more locally advanced the disease is, the more invasive the resection should be.2 During the intervention, in fact, every possible effort must be attempted to keep the cystic lesion intact, avoiding the rupture or inadvertent spillage of the mucoid material into the peritoneal cavity: such complications, in fact, lead to the development of pseudomyxoma peritonei, a condition encumbered by a far worse prognosis than the one associated with AM. CT is recognized as the most proper imaging tool for the preoperative diagnosis of AM.3 Classically, it shows a cystic dilatation of the appendix lumen ranging from 1 to 14 cm in size where wall
calcifications are frequent.3 CT also permits the differential diagnosis with other lesions localized in the right lower quadrant of the abdomen, such as common appendicitis, mesenteric, duplication and urachal cysts, lymphangioma, abscess and haematoma.3 A further advantage of this imaging modality was furnished in 2013 by Wang and colleagues who tested its utility for differentiating preoperatively malignant from benign forms of AM: of interest, the presence of wall irregularity and soft-tissue thickening resulted to indicate a malignant pattern of AM.4 Although there is a need for more works, their results, if corroborated, could represent a valid preoperative guide, helping the surgeons act the best operative tactics for the patients with benign or malignant AM.
References 1. Rampone B, Roviello F, Marrelli D, Pinto E. Giant appendiceal mucocele: report of a case and brief review. World J. Gastroenterol. 2005; 11: 4761–3. 2. Dhage-Ivatury S, Sugarbaker PH. Update on the surgical approach to mucocele of the appendix. J. Am. Coll. Surg. 2006; 202: 680–4. 3. Demetrashvili Z, Chkhaidze M, Khutsishvili K et al. Mucocele of the appendix: case report and review of literature. Int. Surg. 2012; 97: 266–9. 4. Wang H, Chen YQ, Wei R et al. Appendiceal mucocele: a diagnostic dilemma in differentiating malignant from benign lesions with CT. AJR Am. J. Roentgenol. 2013; 201: W590–5.
Fig. 1. Abdominal computed tomography scan showing a giant appendiceal mucocele of 9 cm × 4 cm in size (red arrow) with mixed content (air-fluid and hyperdense material) and wall calcifications (a: axial view; b: sagittal view).
© 2015 Royal Australasian College of Surgeons
ANZ J Surg •• (2015) ••–••
2
Images for surgeons
Edoardo Virgilio, MD Anna Tallerini, MD Paola Addario Chieco, MD Giorgio Castagnola, MD Marco Cavallini, MD Medical and Surgical Sciences and Translational Medicine, Faculty of Medicine and Psychology ‘Sapienza’, St. Andrea Hospital, Rome, Italy doi: 10.1111/ans.13159
Fig. 2. Intraoperative view of the giant appendiceal mucocele.
© 2015 Royal Australasian College of Surgeons
