Case Report
Copyright ©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Jul 16, 2022; 10(20): 7076-7081
Published online Jul 16, 2022. doi: 10.12998/wjcc.v10.i20.7076
Malignant transformation of primary mature teratoma of colon: A case report
Jie Liu
Jie Liu, Department of Pathology, The First Affiliated Hospital of Anhui Medical University, Hefei 230000, Anhui Province, China
Author contributions: Liu J contributed to manuscript writing, picture processing, data analysis and constructive discussions.
Informed consent statement: Written informed consent was obtained from the patient for publication of this case report and accompanying images.
Conflict-of-interest statement: The author has no conflict of interest to disclose.
CARE Checklist (2016) statement: The author has read the CARE Checklist (2016), and the manuscript was prepared and revised according to the CARE Checklist (2016).
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Jie Liu, MM, Doctor, Department of Pathology, The First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Street, Shushan District, Hefei 230000, Anhui Province, China. lj_ayfy@126.com
Received: December 19, 2021
Peer-review started: December 19, 2021
First decision: February 8, 2022
Revised: February 21, 2022
Accepted: May 27, 2022
Article in press: May 27, 2022
Published online: July 16, 2022
Abstract
BACKGROUND

Mature teratoma is a common benign ovarian germ cell tumor, accounting for about 20% of ovarian tumors. The malignant transformation of this tumor is less than 2%. The most common type is squamous cell carcinoma, followed by adenocarcinoma. Malignant transformation of colonic mature teratoma is extremely rare. We here report a case of malignant transformation of primary mature teratoma of the colon. The type of malignant transformation was adenocarcinoma.

CASE SUMMARY

A 63-year-old woman was admitted to our hospital due to persistent pain in her right lower abdomen for 1 mo, and she had no nausea, vomiting, blood in the stools, or other symptoms. Preoperative colonoscopy showed uplift of the sigmoid colon mucosa and submucosa. The biopsy showed squamous epithelium. However, contrast-enhanced computed tomography of abdomen and pelvis showed a localized thickening of the sigmoid wall, suggesting colon cancer. Endoscopic ultrasonography (EUS) revealed that the structure of the intestinal wall at the base of the lesion was destroyed, and the boundary between the lesion and the surroundings was unclear. According to the findings of the EUS, the patient did not undergo endoscopic submucosal dissection, but underwent radical resection of the tumor. Histologically, squamous epithelium was seen on the mucosal surface of the colon wall, cartilage and glands were seen under the epithelium, and adenocarcinoma was seen on the muscular layer and serous surface. The final pathological diagnosis was malignant teratoma of the colon. We have followed up the patient for 2 mo since the operation, and the patient recovered well.

CONCLUSION

This case suggests the possibility of mature teratoma in the colon and recognition of malignant types, and it should not be considered as an exclusively ovarian tumor.

Keywords: Colon, Mature teratoma, Malignant transformation, Adenocarcinoma, Squamous epithelium, Case report

Core Tip: Mature teratoma is a benign tumor that originates from germ cells. The most common site of mature teratoma is the ovaries, and it rarely occurs in the colorectum and rarely undergoes malignant transformation. We report a case of malignant transformation of mature teratoma of the sigmoid colon. Through the analysis of the symptoms, treatment and prognosis, clinicians and pathologists can be aware of the disease, and should prompt patients to receive early clinical intervention and treatment to obtain better therapeutic effect and prognosis.