Sclerosing angiomatoid nodular transformation of the spleen is a recently described benign pathologic entity that is characterized by round shaped vascular spaces that are lined by endothelial cells, and the spaces are circumscribed by granulomatoid structures. Microscopically, all the reported cases had multiple angiomatoid nodules in a fibrosclerotic stroma. Each angiomatoid nodule was made up of slit-like, round or irregular shaped vascular spaces that were lined by endothelial cells and interspersed ovoid cells. We present here the CT and dynamic gadolinium-enhanced MR findings of a patient with sclerosing angiomatoid nodular transformation. The spoke-wheel pattern that was observed on MRI in this case may be an important imaging clue for making the correct diagnosis of this benign lesion.
Adult ; Cell Transformation, Neoplastic/pathology ; Gadolinium/diagnostic use ; Histiocytoma, Benign Fibrous/*pathology/*radiography ; Humans ; *Magnetic Resonance Imaging ; Male ; Splenic Neoplasms/*pathology/*radiography ; *Tomography, X-Ray Computed

Malignant kidney neoplasms are the most frequently encountered solid kidney masses. Although renal cell carcinoma is the major renal malignancy, other solid malignant renal masses should be considered in the differential diagnosis of solid renal masses that do not contain a macroscopic fatty component. In this pictorial essay, we present the imaging findings of a primitive neuroectodermal tumor, primary liposarcoma of the kidney, primary neuroendocrine tumor, leiomyosarcoma, synovial sarcoma, malignant fibrous histiocytoma, sclerosing fibrosarcoma and renal metastasis of osteosarcoma.
Bone Neoplasms/secondary ; Carcinoma, Renal Cell/pathology/radiography ; Diagnosis, Differential ; Fibrosarcoma/radiography ; Histiocytoma/radiography ; Humans ; Kidney Neoplasms/*pathology/radiography ; Leiomyosarcoma/pathology/radiography ; Magnetic Resonance Imaging ; Middle Aged ; Neuroectodermal Tumors, Primitive/pathology/radiography ; Osteosarcoma/pathology ; Sarcoma ; Sarcoma, Synovial/radiography ; Tomography, X-Ray Computed

Imaging features of metastases to the urinary system may closely mimic primary urinary tract tumors, and differential diagnosis by imaging alone may be problematic or even impossible in some cases. The main purpose of this article was to familiarize radiologists with imaging findings of metastasis to the urinary system on cross-sectional imaging, with an emphasis on abdominal and pelvic computed tomography and magnetic resonance imaging. In addition, we review the clinical importance and implications of metastases to the urinary tract and provide information on diagnostic work-ups.
Diagnosis, Differential ; Kidney ; Magnetic Resonance Imaging ; Neoplasm Metastasis ; Ureter ; Urethra ; Urinary Bladder ; Urinary Tract