Mucinous adenocarcinoma of the intestinal type arising from mature cystic teratoma of the ovary: a rare case report and review of the literature

Abstract

Background: Mature cystic teratomas (MCTs) are the most common germ cell tumors of the ovary. Malignant tranformation occurs in 1-2% of these neoplasms. Although most of the malignancies arising from MCTs are squamous cell carcinomas, adenocarcinoma of the gastrointestinal type is extremery rare. We herein present a case of adenocarcinoma of the intestinal type arising from a MCT.

Case: A 49-year-old female underwent surgery for a left ovarian tumor. The histology of the cyst walls revealed a MCT with a few hair shafts and a squamous layer, while another part of the tumor showed adenocarcinoma of the intestinal type. Five years after surgery, she is alive without disease.

Figure 1

Transvaginal ultrasonography. Transvaginal ultrasonography showed a multilocular cystic lesion without a solid part in the pelvic cavity.

Figure 2

MRI findings before surgery. Horizontal T2-weighted (A) and T1-weighted (B) MR imaging demonstrated a fat component, which showed a drop in the signal intensity on fat saturated T1-weighted images (C) in the multilocular cystic lesion without a solid part (arrow).

Figure 3

The gross appearance of the tumor. A 3 cm slightly yellowish solid part (arrows) was observed.

Figure 4

Microscopic findings[1]. The cells which formed the lumen of cysts were mostly columnar epithelium, with some goblet cells. (H&E x20, bar = 500 μm).

Figure 5

Microscopic findings[2]. The consistency of the small glandular cavity was high, and severe dyskaryotic cells had become multilayered, with stromal invasion. (H&E x200, bar = 50 μm).

Figure 6

Immunohistchemical staining. CK7 (A) and Muc-5AC (C) were negative. CK20 (B) and Muc-2 (D) were positive.

Figure 7

Microscopic cross-section through the tumor. The tumor contained components of squamous layer, sebaceous gland (black arrow), fat tissue (arrow head) and atypical grand (white arrow). (H&E x4).