Teratoma with Malignant Transformation: A Case Report with Pathological, Cytogenetic, and Immunohistochemistry Analysis

Abstract

Background. Teratoma with malignant transformation (TMT) is rare and most commonly encountered in adult patient with germ cell tumor (GCT). Method. We report a rare case of testicular teratoma with metastatic TMT/embryonal rhabdomyosarcoma (ERMS). A 44-year-old man underwent right orchiectomy which revealed a malignant teratoma, he subsequently had right pneumonectomy with two pulmonary masses containing a high-grade embryonal rhabdomyosarcoma. The patient developed liver metastasis three months after initial diagnosis. He was treated with a chemotherapy regimen with vincristine, dactinomycin, and cyclophosphamide (VAC) alternating with vincristine and irinotecan (VI) with complete resolution of his liver lesion. The tumors were examined with a battery of cytogenetic, immunohistochemical, and molecular assays. Results. The malignant cells were immunohistochemically positive for desmin, myogenin, and MyoD1. Molecular cytogenetics of embryonal rhabdomyosarcoma tissue revealed the presence of i(12p). The tumor expressed high level of TOPO2A, TOPO1, MRP1, MGMT, BCRP, ERCC1, RRM1, and TS. Conclusion. The activity of topoisomerase inhibitors and the potential usefulness of topoisomerase expression as biomarkers should be further tested in aprospective study.

The Case of an Elderly Male Patient with Unknown Primary Mucinous Adenocarcinoma within Presacral Teratoma (Teratoma with Malignant Transformation)

“…Teratomas are tumors containing different types of cells developing from multiple germinal layers. Most of teratomas are seen in testicles and ovaries of adolescents [ 4 , 7 , 9 ]. However, it may also develop in sacrococcygeal, presacral, retroperitoneal, postanal or mediastinal, and pineal gland, which are also known as midline structures.…”

“…Different hypotheses were proposed, in regard to the development of teratomas. “Germ cell theory” is the most widely accepted one proposing that primitive totipotential cells act as a “wandering germ cell,” arisen from cells left behind during migration of embryonic germ cells from yolk sac to the gonads [ 9 ].…”

“…Primary presacral teratomas are highly rare in adults. Its malignant transformation rate is about 1% [ 9 ]. In the literature, we did not find any case of presacral teratoma that showed malignant transformation, in older adults.…”

“…In adults, malignant transformation rate of primary teratomas settled in presacral region was about 1%. Adult teratomas may be transformed into squamous cell carcinoma, adenocarcinoma, sarcoma, and other malignancies [ 4 – 9 ].…”

Intrapulmonary cystic teratoma mimicking malignant pulmonary neoplasm

“…Regimens containing doxorubicin and cyclophosphamide can be used in sarcomatous TMTs. Cisplatin based regimens can be used for carcinomatous TMTs 9 10…”