Appendiceal adenocarcinoma-Two unique cases of adenocarcinoma ex-goblet cell carcinoid

Appendiceal goblet cell adenocarcinoma newly classified by WHO 5th edition: a case report (a secondary publication)

BACKGROUND

Appendiceal goblet cell adenocarcinoma (AGCA) is a newly proposed cancer type in the 5th edition of the WHO Classification of Tumours in 2019. We experienced this rare form of appendiceal primary neoplasm.

CASE PRESENTATION

An 85-year-old male presented a positive fecal occult blood test. A series of imagings revealed a type 1 tumor, located on the appendiceal orifice. The subsequent biopsy made the diagnosis of signet-ring cell carcinoma. Consequently, he underwent the laparoscopic-assisted ileocecal resection. Initially, the tumor was suspected to be a Goblet cell carcinoid (GCC). There was a discrepancy between the histological and immunostaining findings: the tumor cells exhibited morphological similarities to GCCs, however displayed limited staining upon immunostaining. Ultimately, we concluded that the tumor should be classified as AGCA, by following WHO 5th Edition. AGCA represents a newly categorized subtype of adenocarcinomas. Because of our preoperative suspicion of malignancy, we performed tumor resection with regional lymph node dissection, despite the fact that most appendiceal malignant tumors are typically identified after an appendectomy.

CONCLUSION

We experienced a case that provides valuable insights into the comprehension of AGCA, a recently established pathological entity in the WHO 5th Edition. This article is an acceptable secondary publication of a case report that appeared in Azuma et al. (J Jpn Surg Assoc 83:1103-1108, 2022).

Composite intestinal adenoma-microcarcinoid: An update and literature review

Composite intestinal adenoma-microcarcinoid (CIAM) is a rare intestinal lesion consisting of conventional adenoma and small, well differentiated carcinoid [microcarcinoid (MC)] at its base. The incidence of CIAM is 3.8% in surgically resected colorectal polyps. While its pathogenesis is unknown, studies support the role of Wnt/β-catenin pathway in the tumorigenesis of CIAM. CIAMs have been primarily reported in the colon wherein they present as polyps with well-defined margins, similar to conventional adenomatous polyps. MC is usually found in adenomatous polyps with high-risk features such as large size, villous architecture, or high grade dysplasia. Histologically, the MC component is often multifocal and spans 3.9 to 5.8 millimeters in size. MC is usually confined within the mucosa but occasional CIAM cases with MC extending to the submucosa have been reported. MC of CIAM demonstrates bland cytology and inconspicuous proliferative activity. The lesional cells are positive for synaptophysin and 60% to 100% of cases show nuclear β-catenin positivity. MC poses a diagnostic challenge with its morphologic and immunohistochemical resemblance to both benign and malignant lesions, including squamous morules/metaplasia, adenocarcinoma, squamous cell carcinoma, sporadic neuroendocrine tumor and goblet cell adenocarcinoma. CIAM is an indolent lesion with a favorable outcome. Complete removal by polypectomy is considered curative. Awareness and recognition of this rare entity will help arrive at correct diagnosis and improve patient care. Currently, CIAM is not recognized as a subtype of mixed neuroendocrine-non-neuroendocrine neoplasm by WHO.

Prevalence of Carcinoma in Appendectomy Specimens for Patients Presenting With Acute Appendicitis: A Single-Center Study

Introduction Acute appendicitis is the most common general surgical emergency globally. Its etiology includes the presence of luminal obstruction by faecoliths, lymphoid hyperplasia, impacted stool, and rarely by appendiceal or caecal cancer. Malignancy related to acute appendicitis is usually seen in the older age group. Aim To identify the subset rate of patients operated for acute appendicitis who have appendiceal carcinoma and analyze the outcome of their post-operative management. Material and methods A retrospective study of a cohort of 529 patients aged > 40 diagnosed with acute appendicitis with subsequent appendectomy in the period between 1 January 2014 and 31 December 2019 at Basildon and Thurrock University Hospital, Essex, United Kingdom was conducted. We analyzed the clinical data of the cohort including demographic information, diagnosis, pre-operative imaging, histological diagnosis as well as post-operative management where indicated. Results The median age of patients was 54.5 years (range 40-92). The male to female ratio in the appendicectomy cohort was 1:1.1. About 45% were aged 40-49 years, 24.8% were aged 50-59 and 30.2% were ≥60 years. Post-operative histology revealed acute appendicitis in 82.4% of the group. In 11% of the patients, the histology revealed the presence of other benign pathology as mucocele of the appendix, acute diverticulitis, follicular hyperplasia, and fibrous obliteration. The diagnosis of appendicular malignancy was seen in 1.9%. Conclusion Incidental appendiceal cancers in the resected specimens after acute appendicitis are rare but may be associated with a poor prognosis. It is recommended to consider such diagnosis in particular when dealing with acute appendicitis in older patients with longer symptom history, and in presence of peri-appendicular mass.