Mucin-secreting Adenocarcinoma of the Appendix Presented as Abdominal Lump with Distension: A Case with Diagnostic Dilemma

Abstract

Appendicular adenocarcinoma is a rare tumour, and the mucin variety is common. It is usually presented with symptoms such as abdominal pain, abdominal tenderness, nausea, vomiting, change in bowel habits, and unexplained weight loss. These symptoms can resemble those of other clinical conditions, making the diagnosis of appendicular adenocarcinoma challenging. Screening modalities such as Magnetic Resonance Imaging (MRI), Computed Tomography (CT) imaging, Contrast-Enhanced Computed Tomography (CECT), blood tests, and histopathological analysis can help confirm the diagnosis. This case is reported to highlight the unusual presentation and diagnostic difficulties associated with appendiceal adenocarcinoma. A 48 years old female patient presented with complaints of dull, continuous abdominal pain for the past six months, along with an abdominal lump and distension, without any other associated symptoms. Laboratory investigations for Cancer Antigen 125 (CA 125), β-Human Chorionic Gonadotropin (HCG), and α-fetoprotein were found to be within normal limits. Further, CECT imaging was suggestive of mucin-secreting adenocarcinoma of ovarian origin. The final diagnosis was confirmed by histopathological analysis as mucinsecreting adenocarcinoma of the appendix with pseudomyxoma peritonei and was managed through cytoreduction surgery.