Urothelial carcinoma with trophoblastic differentiation: Reappraisal of the clinical implication and immunohistochemically features

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.

Case report: Urothelial carcinoma of the renal pelvis with trophoblastic differentiation: A rare case report and review of literature

We report a rare case of urothelial carcinoma (UC) of the renal pelvis with trophoblastic differentiation that occurred in a 55-year-old male patient. The patient presented with gross hematuria and paroxysmal lumbago pain 5 months ago. The enhanced computed tomography (CT) scan demonstrated a large space occupying lesion in the left kidney and multiple retroperitoneal lymph node enlargements. Histologically, high-grade infiltrating urothelial carcinoma (HGUC) contained giant cells which were positive for beta-human chorionic gonadotropin (β-hCG). Three weeks after resection, positron emission tomography and computed tomography (PET-CT) scan showed multiple nodules of metastasis in the left renal region, extensive systemic muscle, bone, lymph node, liver and bilateral lung metastases. The patient underwent bladder perfusion chemotherapy and gemcitabine combined with cisplatin chemotherapy regimens. This is the eighth documented case of UC of the renal pelvis with trophoblastic differentiation. Due to its rarity and extremely poor prognosis, it is important to clarify the characteristics of the disease and make an accurate and prompt diagnosis.

Urothelial Carcinoma: Divergent Differentiation and Morphologic Subtypes

Urothelial carcinoma (UC) is known to encompass a wide spectrum of morphologic features and molecular alterations. Approximately 15% to 25% of invasive UC exhibits histomorphologic features in the form of "divergent differentiation" along other epithelial lineages, or different "subtypes" of urothelial or sarcomatoid differentiation. It is recommended that the percentage of divergent differentiation and or subtype(s) be reported whenever possible. Recent advances in molecular biology have led to a better understanding of the molecular underpinning of these morphologic variations. In this review, we highlight histologic characteristics of the divergent differentiation and subtypes recognized by the latest version of WHO classification, with updates on their molecular and clinical features.