# Mucinous Cystadenocarcinoma Arising From a Mature Cystic Teratoma

## TL;DR

This paper reports a rare case of a woman diagnosed with a rare type of ovarian cancer that developed from a benign tumor.

## Contribution

The novelty lies in presenting a clinical case of mucinous cystadenocarcinoma arising from a mature cystic teratoma.

## Key findings

- A woman presented with a large abdominal mass and ascites, later diagnosed as mucinous cystadenocarcinoma.
- Histopathological analysis confirmed the tumor originated from a mature cystic teratoma.
- The case highlights the diagnostic challenges of distinguishing between malignant transformation and collision tumors.

## Abstract

Mucinous cystadenocarcinoma arising from mature cystic teratoma is an uncommon entity. The possibilities are either due to malignant transformation of benign teratoma into adenocarcinoma or a collision tumor between a mature cystic teratoma and a mucinous tumor. Here we present a case of a woman with abdominal distension and vague abdominal pain. Ultrasound abdomen showed a huge heterogeneous space-occupying lesion extending from the pelvis to the epigastrium with non-visualisation of the ovary, suggesting an ovarian origin. Further characterisation by contrast-enhanced computed tomography confirmed a hemorrhagic abdominopelvic multiseptate cystic lesion along with massive ascites. After surgery, the histopathological examination revealed mucinous cystadenocarcinoma arising from the mature cystic teratoma.