Abstract
Mucinous appendiceal neoplasms are rare and diagnosis is often difficult as patients present with non-specific symptoms often suggestive of appendicitis only and most diagnoses are made following post-surgery histology examination. Here we present a case of a mucinous appendiceal adenocarcinoma with areas of both Low-grade Appendiceal Mucinous Neoplasm and High-grade Appendiceal Mucinous Neoplasm, in a ruptured appendix at a district general hospital. Without early detection and treatment these pathologies can lead to pseudomyxoma peritonei, a syndrome of progressive mucinous ascites. This case highlights the limitations of radiological studies, benefits of diagnostic laparoscopy and provides a rationale for removing the mesoappendix with the appendix during routine appendectomies.