US MR imaging correlation in pathologic conditions of the scrotum.

Ultrasonography (US) is usually the initial imaging modality for evaluation of pathologic conditions of the scrotum. However, magnetic resonance (MR) imaging can be useful as a problem-solving tool when sonographic findings are equivocal. MR imaging allows characterization of scrotal masses as intratesticular or extratesticular and can demonstrate various types of lesions and tissue, including cysts or fluid, solid masses, fat, and fibrosis. MR imaging may be of value when the location of a scrotal mass is uncertain or when US does not allow differentiation between a solid mass and an inflammatory or vascular abnormality. Gadolinium-enhanced MR imaging can help differentiate between a benign cystic lesion and a cystic neoplasm. Gadolinium-enhanced imaging can also be used to demonstrate areas of absent or reduced testicular perfusion, such as in segmental testicular infarct. Finally, MR imaging can demonstrate an intraabdominal undescended testis, which can be difficult to detect with US, and is superior to US in differentiation between an undescended testis and testicular agenesis.

Incidence of benign pathologic findings at partial nephrectomy for solitary renal mass presumed to be renal cell carcinoma on preoperative imaging.

OBJECTIVES: To determine the incidence of benign pathologic findings at partial nephrectomy for a solitary renal lesion when preoperative imaging is reviewed by an experienced team of academic genitourinary radiologists. METHODS: From 1996 to 2004, 143 patients underwent resection of a solitary renal lesion for presumed renal cell carcinoma amenable to partial nephrectomy. Our experienced team of genitourinary radiologists interpreted all preoperative imaging scans. Of the 143 patients, 44 underwent partial nephrectomy for a solitary lesion less than 2 cm, 85 for a lesion 2 to 4 cm, and 14 for a lesion greater than 4 cm. RESULTS: Of the 143 solitary masses resected, 23 revealed benign pathologic findings (16.1%). Ten lesions (43.5%) were angiomyolipomas (AMLs), eight (34.8%) were oncocytomas, three (13.0%) were benign Bosniak-type cysts, and one each was a low-grade spindle cell lesion most consistent with mesoblastic nephroma, and a metanephric adenoma. CONCLUSIONS: A significant fraction of small solitary renal masses presumed to be renal cell carcinoma had benign pathologic findings on resection, despite thorough expert radiologic review. Management should favor parenchyma-sparing approaches, because resection serves not only a therapeutic but also a diagnostic function. Patients should be counseled accordingly when faced with the diagnosis of renal mass.

Extrathoracic solitary fibrous tumor of the pelvic peritoneum with central malignant degeneration on CT and MRI.

We describe a 61-year-old man who presented with an extrathoracic solitary fibrous tumor (SFT) of the pelvic peritoneum with central malignant degeneration as seen on computed tomography (CT), magnetic resonance imaging (MRI), and histopathology. When a central focus of heterogeneity and variable contrast enhancement are identified within a fibrous tumor of the pelvis on CT or MRI, malignant degeneration of an extrathoracic SFT, although rare, should be considered as a diagnostic possibility.

Complications of prostate cancer treatment: spectrum of imaging findings.

The imaging appearances of prostate cancer are well described in the radiology literature, but little has been written about the detection and appearance of the complications of therapy for this disease. The most frequently used treatments for prostate cancer are surgical therapy (eg, radical retropubic prostatectomy, radical perineal prostatectomy), radiation therapy (eg, brachytherapy, external-beam radiation therapy, three-dimensional conformal radiation therapy, intensity-modulated radiation therapy), and cryoablative therapy, each of which may lead to complications with characteristic imaging appearances. Possible complications include lymphocele formation; injuries to the ureter, rectum, and urethra; prostatic necrosis; vesicourethral anastomotic leak and stricture; urethral stricture, necrosis, and fistula; radiation proctitis; transient bladder outlet obstruction; radiation-induced urethritis; urinary incontinence; and erectile dysfunction. With improvements in surgical techniques and advances in technology, complications of therapy for prostate cancer are decreasing but still occur with sufficient frequency to warrant familiarity on the part of radiologists. Knowledge of the diverse spectrum of these complications and their characteristic radiologic features facilitates prompt diagnosis and treatment.