Somatic-type tumor arising in a teratoma of the sigmoid colon:squamous cell carcinoma combined with left ovarian mature teratoma:a case report
YIN Ying-ai
QIN Gui-ping
CAO Min
QI Lin-zhe
BAI Surina
Abstract：Objective: To discuss the clinical and pathological features, diagnosis, and differential diagnosis of squamous cell carcinoma arising from a teratoma in the sigmoid colon combined with a mature cystic teratoma of the left ovary. Methods: A retrospective analysis of the clinical data of one case of squamous cell carcinoma arising from a teratoma in the sigmoid colon combined with a mature cystic teratoma of the left ovary was performed. Hematoxylin-eosin (HE) staining and immunohistochemical EnVision two-step method were used to analyze the histopathological features, and relevant literature was reviewed. Results: The patient underwent radical resection of the sigmoid colon and removal of the left ovarian mass. Intraoperatively, the masses in the sigmoid colon and the left ovary were two independent lesions without adhesion. The sigmoid colon showed a mixed cystic and solid mass, mainly invading from the submucosa to the serosa, with partial rupture of the mass. Microscopically, the cystic area contained skin, skin appendages, bronchial gland epithelium, fat, and cartilage tissue, while the solid area showed well-differentiated squamous cell carcinoma, with a transition between the cystic and solid areas. The left ovary showed a cystic mass with a smooth surface, and the cut surface contained oil and hair. Microscopically, it exhibited the histological features of a mature teratoma. All tissue samples were examined and no immature or malignant changes were found. Conclusion: Teratomas in the sigmoid colon are rare clinically, and their malignancy into squamous cell carcinoma is even rarer. Pathologists need to thoroughly sample the tissues and combine preoperative imaging findings and intraoperative observations by clinicians for accurate diagnosis.
Keywords：Sigmoid colonTeratoma malignancyOvarian mature teratomaClinical and pathological characteristicsDifferential diagnosis
Publication Date：2025-04-28
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：3( 439-441 )