Malignant transformation of ovarian mature cystic teratoma with a predominant pulmonary type small cell carcinoma component

Abstract

A 68-year-old woman was diagnosed with mature cystic teratoma of the left ovary when she was 44 years old. The tumor recently enlarged rapidly, and abdominal magnetic resonance imaging revealed an intrapelvic cystic lesion, which measured 123 × 120 × 107 mm and contained a mural nodule. Under a clinical diagnosis of malignant transformation of mature cystic teratoma, bilateral salpingo-oophorectomy with total hysterectomy and omentectomy were performed. The resected specimen showed a unilocular cystic lesion containing a well-demarcated mural nodule measuring 35 × 30 × 25 mm in the left ovary. A microscopic examination revealed various types of carcinoma in the mural nodule: pulmonary type small cell carcinoma (65%), adenocarcinoma (25%), squamous cell carcinoma (5%), and transitional cell carcinoma (5%). Small cell carcinoma was positive for CD56, synaptophysin, and chromogranin A. The adenocarcinoma component showed intestinal phenotypes; i.e. cytokeratin (CK) 7(-), CK20(+), CDX2(+), estrogen receptor(-), and progesterone receptor (-). Interestingly, CDX2 positivity was retained in all of the carcinomas. It was assumed that the adenocarcinoma had arisen from an intestinal epithelium in the mature cystic teratoma and then differentiated into the diverse histological types mentioned above.

KRAS mutation positive mucinous adenocarcinoma originating in mature ovarian teratoma: Case report and review of literature

“…Ovarian mature cystic teratomas are usually benign; however, malignancy arises in 1–2% of them, mostly in post‐menopausal women. Squamous and adenocarcinomas are the most common malignancies arising in teratomas, but rare cases such as pulmonary type small cell carcinoma, angiosarcoma and clear cell carcinoma have been described . Among the carcinomas squamous cell carcinoma (SCC) account for 80% of cases .…”

Neuroendocrine Tumors of the Female Reproductive Tract: A Literature Review

“…In a previous study, eight of 11 SCCOPT cases were associated with surface epithelial tumors [ 59 ]. Rare cases arising in an ovarian teratoma have been reported [ 61 , 62 ]. A diagnosis of SCCOPT can be made in the absence of neuroendocrine marker positivity if the morphologic appearance is typical SCNEC.…”

Mature Cystic Teratoma of Ovary With Mucinous Epithelial Neoplasm and Malignant Mural Nodule. A Case Report and Review of the Literature

“…This is however, rare, occurring in up to 2% of cases (1,2). This is however, rare, occurring in up to 2% of cases (1,2).…”