Sarcomatoid Urothelial Carcinoma with Choriocarcinomatous Features: First Report of an Unusual Case

Aberrant trophoblastic differentiation in human cancer: An emerging novel therapeutic target (Review)

Various types of human cancer may develop aberrant trophoblastic differentiation, including histological changes and altered expression of β‑human chorionic gonadotropin (β‑hCG). Aberrant trophoblastic differentiation in epithelial cancer is usually associated with poor differentiation, tumor metastasis, unfavorable prognosis and treatment resistance. Since β‑hCG‑targeting vaccines have failed in an early phase II trial, it is crucial to obtain a better understanding of the molecular pathogenesis of trophoblastic differentiation in human cancer. The present review summarizes the clinical and translational research on this topic with the aim of accelerating the development of an effective targeted therapy. Ectopic expression of β‑hCG promotes proliferation, migration, invasion, vasculogenesis and epithelial‑mesenchymal transition (EMT) in vitro, and enhances metastatic and tumorigenic capabilities in vivo. Signaling cascades modulated by β‑hCG include the TGF‑β receptor pathway, EMT‑related pathways, the c‑MET receptor tyrosine kinase and mitogen‑activated protein kinase/ERK pathways, and the SMAD2/4 pathway. Taken together, these findings indicated that TGF‑β receptors, c‑MET and ERK1/2 are potential therapeutic targets. Nevertheless, further investigation on the molecular basis of aberrant trophoblastic differentiation is mandatory to improve the design of precision therapy for this aggressive type of human cancer.

[A case of urothelial carcinoma with trophoblastic differentiation and review of the literature]

We report the case of a 43-year-old woman, who was admitted for intense pelvic pains. Biological investigations showed an increase of β-HCG level. The abdomino-pelvic computed tomography revealed a voluminous mass infiltrating the bladder. A transurethral resection was performed. The histopathological examination evidenced an invasion of the bladder by a massive carcinomatous proliferation composed of clear epithelial cells with in some places syncytiotrophoblastic cells and rarely cytotrophoblastic cells. Immunohistochemical analyses revealed a staining of GATA-3 by the two components, an expression of p63 by the clear cell urothelial component and the immunoreactivity of β-HCG by the trophoblastic component. Ki-67 labeling index was very high. The diagnosis of mixt urothelial carcinoma with clear cells and trophoblastic differentiation was proposed. This is a rare difficult histopathological diagnosis which should be known by pathologists. It is correlated to a poor clinical outcome with a high tendency to lymph node or visceral metastases.

Carcinosarcoma with Choriocarcinomatous and Osteosarcomatous Differentiation in a Patient with Juvenile Polyposis Syndrome

Juvenile polyposis syndrome (JPS) is an infrequent autosomal dominant hereditary predisposition to the occurrence of hamartomatous polyps in the colon and rectum. We describe the case of a 12-year-old boy with JPS associated with an abdominal tumor. Histological sections of the abdominal tumor showed components of adenocarcinoma, osteosarcoma, and choriocarcinoma. Immunohistochemistry was AE1/AE3, CK7, HCG and SALL4 positive. Juvenile polyposis syndrome patients are at increased risk of colorectal adenocarcinoma. However, we present a case of an adenocarcinoma associated with other unusual components. This association has not been reported before.

The many faces of urothelial carcinoma: an update with an emphasis on recently described variants

Urothelial carcinoma is well known for its divergent differentiation. Several "variant" morphologies have been described in the literature in recent years and have additionally been recognized in the recent World Health Organization classification of urothelial neoplasms. The importance of recognizing these variant histologies lies in the potential diagnostic, prognostic, or therapeutic implications that accompany these diagnoses. The range of variant morphology seen in the urinary bladder may also be seen in urothelial tumors of the renal pelvis. Herein we review select variants of urothelial carcinoma focusing on the relatively recently recognized variants, outlining the diagnostic features, common differential diagnostic dilemmas, and clinical relevance. This review also includes a discussion on variants on which there is recent information available.