[Uretral carcinosarcoma. Case report].

Objective: Carcinosarcoma is a neoplasia with malignant epithelial and mesenchymal differentiation. Carcinosarcoma of the urinary tract is a rare neoplasm. It is an extremely rare entity in the ureter.

[Metanephric adenoma. Case report].

Objective: Metanephric adenoma is an unfrequent renal neoplasm, usually asymptomatic. Differential diagnosis with other renal tumors has to be performed.

Methods/results: We report the case of a 67 years old woman with a metanephric adenoma.

[Papillary urothelial carcinoma of the urachus].

Objective: Persistence of a patent urachus is a relatively rare occurrence; however; the persistence of urachal remnants is common. The pathologic lesions of the urachus include benign and malignant neoplasms. The majority of malignant urachal neoplasms are adenocarcinomas.

[Prostatic stromal sarcoma in a 20-year-old patient].

Objective: Prostatic tumors are the most frequent malignant neoplasms in men, most of them being constituted by carcinomas; only 0.2% of malignant prostatic neoplasms are of mesenchimal origin. They are not well known, especially those of prostatic stromal phenotype.