Saturday, October 4, 2008

Testicular Tumours: Choriocarcinoma

Choriocarcinoma is a highly malignant tumour composed of both cytotrophoblastic and syncytiotrophoblastic elements. It is a rare germ cell tumour.
It develops in patients in the 2nd and 3rd decades of life.
Similar neoplasms may occur in the ovary, placenta, or ectopic pleuripotential germ cell rests in other sites (Example: mediastinum, abdomen).
The neoplasm is rare in pure form within the testis. It is more often seen as a component of a mixed germ cell tumour.
The levels of human chorionic gonadotropin are elevated and cause gynecomastia in 10% of cases Grossly, the primary testicular tumour is often quite small even in the presence of widespread systemic metastases. The gross appearance ranges from a bulky, hemorrhagic mass to an inconspicuous lesion replaced by a fibrous scar.
Microscopically, it is composed of both polygonal, comparatively uniform cytotrophoblasts growing in sheets and cords, admixed with multinucleated syncytiotrophoblasts. Well-developed villi are not seen.
Syncytiotrophoblasts stain positively for chorionic gonadotropin.
Often, there is early widespread metastasis, and patients may present with symptoms referable to their metastases rather than a palpable testicular mass. Sites of metastases include the lung, liver, gastrointestinal tract, and brain. The primary tumour and metastases are often hemorrhagic.
Choriocarcinoma has the worst prognosis of any of the germ cell tumors, with death usually occurring within 1 year of diagnosis.

Abstracts: Metastatic testicular choriocarcinoma of the skin. Report and review of the literature.Am J Dermatopathol.1996 Dec;18(6):633-6.
Choriocarcinoma is a malignant growth of trophoblastic cells characterized by secretion of human chorionic gonadotropin. Choriocarcinoma usually arises from fetal trophoblasts and rarely arises from germ cells in the testis or ovary or derives from dedifferentiation of other carcinomas. Skin metastasis of choriocarcinoma is rare: only seven cases have been reported in the English and Japanese literature. We report the case of a 22-year-old Japanese man with pure choriocarcinoma of the testis who developed skin metastases that presented as multiple reddish nodules. Microscopic examination of both the primary lesion of the testis and the cutaneous metastasis demonstrated the typical histologic features of pure choriocarcinoma. The patient died 3 months after the initial onset of skin metastasis. Review of the literature indicates that skin metastasis of choriocarcinoma usually occurs as a nodular lesion with the histologically typical feature of the primary disease and signals of poor prognosis.