Mucinous adenocarcinoma of the appendix
Updates to Article Attributes
Mucinous adenocarcinomas of the appendix are withinon the malignant end of the spectrum of the mucinous neoplasms that affect the caecal appendix.
For the mucinous carcinomas involving the remainder of the colon, please refer to the article on mucinous carcinoma of the colon.
Epidemiology
Peak incidence in the 6th and 7th decades 1,3. Associations with other colonic neoplasia and chronic ulcerative colitis have been reported 1.
Clinical presentation
Symptoms are much more likely to happen than in the other more indolent appendiceal neoplasms (e.g. adenoma or neuroendocrine tumours). The spectrum of symptoms varies from a vague abdominal pain, nausea, vomiting, and weight loss, to a palpable mass, abdominal distension, and acute appendicitis1,3.
Pathology
Considerable controversy still exists on mucinous neoplasms of the appendix pathologic classification and nomenclature 1. According to a panel of specialist review in 2016, a new nomenclature and classification for the appendiceal mucinous neoplasms based on their histologic type and biologic behaviour has been proposed and since then the term mucinous adenocarcinoma should be reserved for the mucinous tumours that have an infiltrative invasion beyond the muscularis mucosa 1,2.
An adenocarcinoma is defined as mucinous when extracellular mucin corresponds to more than 50% of the lesion. The signet ring cell carcinoma variant occurs when a tumour has more than 50% of cells showing the classical signet ring morphology 1,2.
Radiographic features
Fluoroscopy
Barium enema
Nonspecific signs may indicate a tumoural lesion adjacent to the caecum, including the non-filling of the appendix, a submucosal mass lesion at the caecal pole, and an extraluminal compression of the caecum 1.
Treatment and prognosis
Staging and management of these are different from those of colorectal carcinoma, please refer to the appendiceal mucinous neoplasms TNM staging for further details.
-<p><strong>Mucinous adenocarcinomas of the appendix</strong> are within the malignant end of the spectrum of the <a title="Mucinous neoplasms of the appendix" href="/articles/mucinous-neoplasms-of-the-appendix">mucinous neoplasms that affect the caecal appendix</a>. </p><h4>Epidemiology</h4><p>Peak incidence in the 6<sup>th</sup> and 7<sup>th</sup> decades <sup>1,3</sup>. Associations with other colonic neoplasia and chronic ulcerative colitis have been reported <sup>1</sup>. </p><h4>Pathology</h4><p>Considerable controversy still exists on mucinous neoplasms of the appendix pathologic classification and nomenclature <sup>1</sup>. According to a panel of specialist review in 2016, a new nomenclature and classification for the appendiceal mucinous neoplasms based on their histologic type and biologic behaviour has been proposed and since then the term mucinous adenocarcinoma should be reserved for the mucinous tumours that have an infiltrative invasion beyond the muscularis mucosa <sup>1,2</sup>. </p><p>An adenocarcinoma is defined as mucinous when extracellular mucin corresponds to more than 50% of the lesion. The signet ring cell carcinoma variant occurs when a tumour has more than 50% of cells showing the classical signet ring morphology <sup>1,2</sup>. </p>- +<p><strong>Mucinous adenocarcinomas of the appendix</strong> are on the malignant end of the spectrum of the <a href="/articles/mucinous-neoplasms-of-the-appendix">mucinous neoplasms that affect the caecal appendix</a>. </p><p>For the mucinous carcinomas involving the remainder of the <a href="/articles/large-intestine-1">colon</a>, please refer to the article on <a href="/articles/mucinous-carcinoma-of-the-colon-1">mucinous carcinoma of the colon</a>.</p><h4>Epidemiology</h4><p>Peak incidence in the 6<sup>th</sup> and 7<sup>th</sup> decades <sup>1,3</sup>. Associations with other colonic neoplasia and chronic ulcerative colitis have been reported <sup>1</sup>. </p><h4>Clinical presentation</h4><p>Symptoms are much more likely to happen than in the other more indolent <a href="/articles/neoplasms-of-the-appendix">appendiceal neoplasms</a> (e.g. <a href="/articles/appendiceal-adenoma">adenoma</a> or <a href="/articles/neuroendocrine-tumour-of-the-appendix">neuroendocrine tumours</a>). The spectrum of symptoms varies from a vague abdominal pain, nausea, vomiting, and weight loss, to a palpable mass, abdominal distension, and <a href="/articles/appendicitis">acute appendicitis</a> <sup>1,3</sup>.</p><h4>Pathology</h4><p>Considerable controversy still exists on mucinous neoplasms of the appendix pathologic classification and nomenclature <sup>1</sup>. According to a panel of specialist review in 2016, a new nomenclature and classification for the appendiceal mucinous neoplasms based on their histologic type and biologic behaviour has been proposed and since then the term mucinous adenocarcinoma should be reserved for the mucinous tumours that have an infiltrative invasion beyond the muscularis mucosa <sup>1,2</sup>. </p><p>An adenocarcinoma is defined as mucinous when extracellular mucin corresponds to more than 50% of the lesion. The signet ring cell carcinoma variant occurs when a tumour has more than 50% of cells showing the classical signet ring morphology <sup>1,2</sup>. </p><h4>Radiographic features</h4><h5>Fluoroscopy</h5><h6>Barium enema </h6><p>Nonspecific signs may indicate a tumoural lesion adjacent to the caecum, including the non-filling of the appendix, a submucosal mass lesion at the caecal pole, and an extraluminal compression of the caecum <sup>1</sup>. </p><h4>Treatment and prognosis </h4><p>Staging and management of these are different from those of <a href="/articles/colorectal-carcinoma">colorectal carcinoma</a>, please refer to the <a href="/articles/appendiceal-mucinous-neoplasms-tnm-staging">appendiceal mucinous neoplasms TNM staging</a> for further details. </p>
References changed:
- 2. Carr N, Cecil T, Mohamed F et al. A Consensus for Classification and Pathologic Reporting of Pseudomyxoma Peritonei and Associated Appendiceal Neoplasia: The Results of the Peritoneal Surface Oncology Group International (PSOGI) Modified Delphi Process. Am J Surg Pathol. 2016;40(1):14-26. <a href="https://doi.org/10.1097/PAS.0000000000000535">doi:10.1097/PAS.0000000000000535</a> - <a href="https://www.ncbi.nlm.nih.gov/pubmed/26492181">Pubmed</a>
- 3. Leonards LM, Pahwa A, Patel MK, Petersen J, Nguyen MJ, Jude CM. Neoplasms of the Appendix: Pictorial Review with Clinical and Pathologic Correlation. Radiographics : a review publication of the Radiological Society of North America, Inc. 37 (4): 1059-1083. <a href="https://doi.org/10.1148/rg.2017160150">doi:10.1148/rg.2017160150</a> - <a href="https://www.ncbi.nlm.nih.gov/pubmed/28598731">Pubmed</a> <span class="ref_v4"></span>
- 1. Tirumani SH, Fraser-Hill M, Auer R, Shabana W, Walsh C, Lee F, Ryan JG. Mucinous neoplasms of the appendix: a current comprehensive clinicopathologic and imaging review. Cancer imaging : the official publication of the International Cancer Imaging Society. 13: 14-25. <a href="https://doi.org/10.1102/1470-7330.2013.0003">doi:10.1102/1470-7330.2013.0003</a> - <a href="https://www.ncbi.nlm.nih.gov/pubmed/23439060">Pubmed</a> <span class="ref_v4"></span>
Systems changed:
- Gastrointestinal