Spontaneous ovarian choriocarcinoma in a young ICR mouse

Subcutaneous choriocarcinomas in captive Amargosa voles (Microtus californicus scirpensis)

Spontaneous choriocarcinomas are rare, highly vascular, malignant trophoblastic tumors that occur in humans and animals. This report describes the unusual spontaneous presentation of 4 choriocarcinomas within the subcutaneous tissues of 4, multiparous but nongravid, Amargosa voles (Microtus californicus scirpensis) from a captive breeding colony. Two subcutaneous neoplasms were composed of multifocal discohesive and infiltrative aggregates of medium to large trophoblasts and cytotrophoblasts within a fibrovascular stroma. Neoplastic cells were associated with variably sized thrombi and cavitary areas of hemorrhage and necrosis. Two subcutaneous tumors were predominantly composed of expansile, blood-filled, cystic spaces lined by neoplastic cytotrophoblasts and occasionally contained medium to large trophoblasts. Trophoblasts and cytotrophoblasts were positive for pancytokeratin and cytokeratin 8/18, negative for alpha-fetoprotein, and contained intracytoplasmic Periodic acid-Schiff (PAS)-positive glycogen in all 4 tumors. In species with hemochorial placentation, migration of trophoblasts into maternal circulation with embolization to distant nonreproductive tissues occurs and may explain the unusual subcutaneous distribution of these 4 tumors. The 2 multiloculated paucicellular tumors may represent an early stage of neoplastic transformation. To the authors' knowledge, this is the first report characterizing choriocarcinomas in extrareproductive sites in rodents.

Primary ovarian choriocarcinoma occurring in a postmenopausal woman: A case report

BACKGROUND

Nongestational ovarian choriocarcinoma (NGOC) is a rare but aggressive neoplasm with limited sensitivity to chemotherapy and a very poor prognosis. Few cases of NGOC have been reported, and there is limited information regarding its clinical features, treatment protocols, or prognosis.

CASE SUMMARY

A postmenopausal woman in her 5^th decade of life visited our clinic because of abnormal vaginal bleeding and an abdominal mass. Although she had been menopausal for more than eight years and her last abortion occurred nine years ago, she had an increased level of serum β-human chorionic gonadotropin (β-hCG). Thus, an ovarian neoplasm of trophoblastic origin was suspected, and exploratory laparotomy was performed. Based on the patient’s clinical history and the histopathological examination and immunohistochemistry results obtained postoperatively, we concluded that she most likely had primary NGOC. Cytoreductive surgery was performed in combination with adjuvant chemotherapy comprising bleomycin, etoposide, and cisplatin. Serum β-hCG levels decreased to normal after two cycles, and there was no evidence of recurrence after four cycles of chemotherapy.

CONCLUSION

Even in postmenopausal women, ovarian choriocarcinoma should be considered in the initial differential diagnosis for an adnexal mass.

Non-Gestational Ovarian Choriocarcinoma: A Rare Ovarian Cancer Subtype

Non-Gestational Ovarian Choriocarcinoma (NGOC) is an extremely rare ovarian tumor, with an incidence of less than 0.6% of malignant ovarian germ cell tumors. Its close pathologic resemblance to Gestational Ovarian Choriocarcinoma (GOC), however, requires special attention as the treatments differ greatly. NGOC typically affects patients in late adolescence or early reproductive years. As a result, NGOCs are often misdiagnosed as ectopic pregnancies due to their common presentation of bleeding, abdominal pain, adnexal mass, and positive serum beta-HCG. On pathologic examination, the tumor is indistinguishable from GOC, and only after review of tissue for paternal genetic components can the diagnosis of NGOC be made. Imaging studies often show highly vascular lesions with further investigation with computer topography (CT) sometimes showing metastatic lesions in the lungs, pelvis, vagina, and liver. These lesions are often hemorrhagic and can lead to catastrophic bleeding. Treatment is vastly different from GOC; NGOC requires treatment with both surgical resection and chemotherapy, with Bleomycin, Etoposide, and Cisplatin (BEP) being the most used regimen. With correct diagnosis and treatment, patients can often receive fertility sparing treatment with long term survival.