[Glomus tumor of kidney: Unusual location of a rare mesenchymal tumor]. / Tumeur glomique rénale : localisation inhabituelle d'une tumeur mésenchymateuse rare.

Glomus tumors are rare mesenchymal tumors, mostly cutaneous or subcutaneous, for which visceral locations have been described. We report the case of a solid renal glomus tumor incidentally discovered in a 60-year-old patient. The tumor was 25mm wide and was mainly composed of glomus cells expressing smooth muscle actin and vimentin. These cells were negative for cytokeratin, neuroendocrine markers and renin. Glomus cells were associated with blood vessels and bundles of smooth muscle fibers. The purpose of this work is to report the diagnostic criteria, signs of malignancy and main differential diagnosis of these rare tumors whose prognosis is usually excellent after complete surgical resection.

Thyroid-like follicular carcinoma of the kidney: a case report and review of the literature.

Thyroid-like follicular carcinoma of the kidney is an extremely rare histological variant of renal cell carcinoma. It was described only recently and is not included in the World Health Organization classification of renal tumors. This tumor characteristically shows similar histology to thyroid follicular carcinoma but lacks typical thyroid markers. Herein, we report a new case of thyroid-like follicular carcinoma of the kidney diagnosed in a partial nephrectomy specimen in a 68-year-old-woman. We present typical histological and immunohistochemical findings, discuss differential diagnosis and provide a review of the literature.Virtual Slides: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_186.

["Growing teratoma syndrome": an unrecognized complication of treated germ cell tumors of the testis]. / Le « growing teratoma syndrome ¼ : une évolution méconnue des tumeurs germinales non séminomateuses traitées du testicule.

"Growing teratoma syndrome" is a rare and often unrecognized complication of nonseminomatous germ cell tumors of the testis. It is defined by enlarging residual masses, frequently retroperitonal, composed exclusively by teratoma, during the course of chemotherapy. Complications of this syndrome are due to masses compression. Malignant transformation is also possible. "Growing teratoma syndrome" has a good prognosis when cured by complete surgical excision of the tumoral masses. We report the case of a "growing teratoma syndrome" presenting as a retroperitoneal mass occurring in a patient previously treated by orchiectomy and chemotherapy for a nonseminomatous mixed germ cell tumors of the testis without teratomatous component.

[Nested variant urothelial carcinoma: diagnostic difficulties]. / Carcinome urothélial a type de nid: difficultés diagnostiques.

Nested variant urothelial carcinoma is a recently identified variant of urothelial carcinoma which is difficult to diagnose due to its resemblance to other benign bladder lesions, such as hyperplasia of Von Brünn nests. The authors present three clinical cases of this variant of urothelial carcinoma and emphasize the importance of clinical, cytological, histological and immunohistochemical criteria for the diagnosis and the need for early and adapted therapeutic management, as this type of bladder tumour, wrongly considered to be benign up until the early 1990s, is just as invasive as high-grade urothelial carcinoma.