Complete appendiceal inversion with local high-grade intraepithelial neoplasia in an adult female: a case report

Abstract

BackgroundAppendiceal inversion with neoplasia in adults is an extremely rare event with a reported incidence of < 0.01%. Preoperative diagnosis is very important for surgical treatment; however, it is very difficult to be exact.Case presentationThe patient was a 60-year-old woman with complaints of intermittent abdominal pain. Computed tomography and colonoscopy revealed a cecal mass, which was diagnosed as a tubulovillous adenoma in the preoperative colonoscopic biopsy. At surgery, the appendix was found to be completely inverted into the cecum. The cecum was partially resected, and surgical pathology examination confirmed a tubulovillous adenoma of the appendix with local high-grade intraepithelial neoplasia.ConclusionsAlthough preoperative diagnosis of appendiceal inversion with neoplasia may be often difficult due to its non-specific symptoms, clinicians should consider this disease entity when they encounter an intraluminal protruding cecal mass without visualization of the normal appendix on CT and colonoscopy.

Inverted Appendix in a Patient With Weakness and Occult Bleeding

“…[2][3][4] Most AMNs, however, are asymptomatic and are usually found incidentally during appendectomies for appendicitis, and can even be found during colonoscopies, such as in this case. 5,6 Low-grade AMNs are distinguished from appendiceal mucinous adenocarcinomas by their lack of wall invasion. 7 Additionally, low-grade AMNs have a very good prognosis as even neoplasms that have spread outside of the appendix have a 5-year overall survival rate of 79 to 86%.…”

“…11 Appendiceal inversion is a rare finding in adults with an estimated prevalence of 0.01%. 6 Not only is appendiceal inversion rare in and of itself, it is even more rarely found in combination with appendiceal neoplasms. 6 Other causes of appendiceal inversion include intussusception, acute appendicitis, appendiceal nodule, or even iatrogenic due to appendectomy.…”

“…6 Not only is appendiceal inversion rare in and of itself, it is even more rarely found in combination with appendiceal neoplasms. 6 Other causes of appendiceal inversion include intussusception, acute appendicitis, appendiceal nodule, or even iatrogenic due to appendectomy. [12][13][14] While appendiceal inversion can be completely benign, because these morphological changes of the appendix can resemble a polyp, these lesions are often biopsied and/or resected.…”

“…25 Additionally, because appendiceal inversion may be seen with AMNs, the patient' s inverted appendix seen during his colonoscopy was another compelling reason for laparoscopic evaluation of his appendix. 6 CONCLUSIONS AMNs can present with nonspecific symptoms or can be completely asymptomatic and are often found incidentally during colonoscopies or appendectomies for acute appendicitis. While it is true that AMNs have low metastatic potential and grow slowly, AMNs can rupture leading to pseudomyxoma peritonei or even cause bowel obstruction warranting timely identification and removal of these neoplasms.…”

Appendiceal Inversion Presenting as a Cecal Polypoid Mass on Screening Colonoscopy: A Case Report and Review of Available Diagnostic Adjuncts to Differentiate Benign From Malignant Colorectal Pathology

“…The proposed advantages of stump inversion include double closure of the cecal wall, decreased contamination from an intra-peritoneal stump, and minimized risk of adhesions [3]. However, there are reports of an appendiceal stump harboring a neoplasm [4][5]. As a result, appendiceal inversion, or what appears as a cecal polyp at the appendiceal orifice on imaging or colonoscopy, must be further investigated and differentiated from a pathologic process.…”