Vermiform Appendix and the Potential for Missed Pathologies

Abstract

Introduction The appendix is considered an appendage of little value and is often treated disdainfully, be it as part of evolutionary process, on a grossing table, under a microscope or while archiving specimens and slides. It is only recently, with data indicating its importance in gut immunity and as the origin of pseudomyxoma, that its space in a human body appears vindicated. Aim Our aim was to screen the histopathologic spectrum of appendix lesions observed in our hospital for rare, incidental or clinico-radiologically uncertain lesions that would help emphasize a necessary seriousness in its sampling. Method All appendectomy specimens over ten years were screened for diagnosis other than acute/chronic/resolving appendicitis and pseudomyxoma peritonei. Among the recorded rare diagnoses, one representative case each, based on interesting history or pathology, was selected for discussion. Observation Forty-three lesions were found to meet inclusion criteria comprising 12 varied etiologies. Among these, 25 had a normal-appearing appendix and 27 were not suspected on radiology or on clinical/surgical assessment. Histopathology comprised, among others, neoplastic entities such as (Diffuse large B-cell) lymphoma, metastasis, carcinoid as well as interesting non-neoplastic diagnoses such as pinworm infestation (in the elderly) and (post-menopausal) endometriosis. Conclusion Sampling and histopathologic assessment of the appendix should be compulsory, careful and representative. Each specimen must be treated as harboring a potential pathology, until microscopically proven otherwise because missed “rare” diagnoses could delay therapy or alter key management decisions as cancer staging.

Appendectomy in endometriosis: an update on surgical indications and management of uncommon diseases

“…The process begins at the appendiceal tip and will proceed proximally over time and may affect the entire appendix. No treatment is required, however, as this is usually found incidentally, the prognosis is related to the underlying condition that led to resection [18][19][20][21][22][23].…”

The Vermiform Appendix and Its Pathologies

“…Several rare conditions linked to the vermiform appendix have been reported in the literature without fitting into any of the three main categories presented above. A retrospective cross-sectional study revealed that some appendectomy specimens were infested with Enterobius vermicularis, i.e., pinworm infection [165]. Other parasites reportedly found in the vermiform appendix include Taenia spp.…”

“…Other parasites reportedly found in the vermiform appendix include Taenia spp. (tapeworm), Hymenolepis nana (dwarf tapeworm), Ascaris lumbricoides (roundworm), Trichuris trichiura (whipworm), Schistosoma haematobium, Schistosoma mansoni, Giardia lamblia, and the protozoan Entamoeba histolytica [165,166]. Such parasite infections may further cause appendicular colic [167] or appendicitis [167][168][169].…”

“…Another rare condition of the vermiform appendix is endometriosis [165]. Appendiceal endometriosis may be asymptomatic or may cause similar manifestations of acute and chronic appendicitis, being also associated with cyclic and chronic right lower quadrant pain, melena, lower intestinal hemorrhage, cecal intussusception, and intestinal perforation [173,174].…”

Intramucosal goblet cell adenocarcinoma: The evil got nipped in the bud

“…There have been other calls for a more thorough examination of the appendix following routine appendectomy. For example, a recent retrospective cross-sectional study showed that a significant portion of rare appendiceal pathologies were not suspected either radiologically or clinically prior to microscopic analysis [11]. Moreover, given the dearth of research with respect to the treatment of patients with appendiceal goblet cell adenocarcinoma, it is important to identify cases of this rare tumor and add to the literature.…”