# Histopathological Diagnosis of a Case of Mucin-Secreting Adenocarcinoma of the Appendix

## TL;DR

This paper presents a case of a rare appendix cancer that secretes mucin and leads to abdominal complications.

## Contribution

The novelty lies in the detailed histopathological diagnosis and treatment approach for a rare mucin-secreting adenocarcinoma of the appendix.

## Key findings

- A 48-year-old female was diagnosed with low-grade mucin-secreting adenocarcinoma of the appendix.
- The tumor was staged as pT4b pNx pM1c with pseudomyxoma peritonei as a complication.
- Treatment involved cytoreductive surgery and hyperthermic intraperitoneal chemotherapy.

## Abstract

Mucin-secreting adenocarcinoma of the appendix is a very rare, slow-growing, mucin-producing epithelial neoplasm of the appendix. It is usually found accidentally in an appendicectomy specimen with the presentation of acute appendicitis in most patients or when there is a rupture of the primary tumor with the mucin spreading along with the tumor cells in the entire peritoneal cavity. Here we describe a case of low-grade (well-differentiated) mucin-secreting adenocarcinoma in the appendix. A 48-year-old female presented with complaints of abdominal distension with no other complaints of fever, pain, or breathlessness. Carcinoembryonic antigen levels were 44.8 ng/mL. Cytoreduction surgery of bilateral ovaries was done. The final histopathological diagnosis was reported as low-grade (well-differentiated) mucin-secreting adenocarcinoma of the appendix staged at pT4b pNx pM1c. Pseudomyxoma peritonei is a very feared complication and also, at times, the only presenting symptom where there is an accumulation of mucin in the intra-abdominal cavity due to the spread of mucin-secreting cells, which in turn causes an increase in the abdominal girth along with discomfort for the patient. The mainstay of treatment remains cytoreductive surgery along with hyperthermic intraperitoneal chemotherapy.