A myeloid sarcoma (MS) is an extramedullary tumor consisting of primitive granulocytic precursor cells. Although most such tumors have been reported in patients with acute myelogenous leukemia, MS is rarely recognized as an isolated tumor without any evidence of leukemia. However, in such cases, the initial diagnosis of MS can be difficult, so initial misdiagnosis rates of up to 75% have been reported. This report describes an unusual case of MS in a 3-year 5-month-old girl presenting as bilateral renal enlargements, and brain masses, with multiple bone involvements, but no hematological abnormalities.
Bone Neoplasms/pathology/*radiography ; Brain Neoplasms/pathology/*radiography ; Child, Preschool ; Female ; Human ; Kidney Neoplasms/pathology/*radiography ; Sarcoma, Granulocytic/pathology/*radiography ; Tomography, X-Ray Computed

Sarcoma of the kidney is a rare condition. Leiomyosarcoma is the most common of the kidney sarcomas. Renal leiomyosarcoma usually originates from the smooth muscle layers of the kidney, for example, the renal capsule and renal vessels. Renal pelvis neoplasms, however, are primarily transitional cell carcinomas, and renal pelvis leiomyosarcomas are extremely uncommon. Renal pelvis leiomyosarcoma has never been reported in Korea. Moreover, no more than 10 cases have been reported internationally. However, none of these were associated with kidney abnormalities. Here we describe a case of leiomyosarcoma that originated from the blind end of a bifid renal pelvis.
Female ; Humans ; Kidney Neoplasms/*pathology ; Kidney Pelvis/*pathology/radiography ; Leiomyosarcoma/*pathology ; Tomography, X-Ray Computed

A case of Wilms' tumor in a 67 year-old female is presented. The tumor totally replaced the left kidney with extension to Gerota's fascia, the adrenal gland and ureter, with tumor thrombi in the left renal vein. Multiple bony metastases to the skull, shoulder, rib, ilium, acetabulum and femur were noted also. Microscopically, the tumor was composed predominantly of blastemal tissue with diffuse anaplasia with areas of tubular differentiation and chondroid elements. Clear cell nests were found in the proximal ureter with gradual maturation downward.
Aged ; Bone Neoplasms/secondary ; Case Report ; Female ; Human ; Kidney/pathology ; Kidney Neoplasms/*pathology/radiography ; Nephroblastoma/*pathology/radiography ; Tomography, X-Ray Computed ; Ureter/pathology

Carcinosarcomas are rare biphasic malignant neoplasms with an epithelial and a spindle cell component. We present a 62-year-old man with a history of noticeably abdominal distension, proved by surgery to be caused by carcinosarcoma of the renal pelvis and urinary bladder, occupying the entire left abdominal flank. We also illustrate the appearance of this rare entity on sonography and computed tomography.
Bladder/*pathology/radiography/surgery/ultrasonography ; Bladder Neoplasms/radiography/*surgery/ultrasonography ; Carcinosarcoma/radiography/*surgery/ultrasonography ; Contrast Media/administration & dosage ; Human ; Kidney Neoplasms/radiography/*surgery/ultrasonography ; Kidney Pelvis/*pathology/radiography/surgery/ultrasonography ; Male ; Middle Aged ; Tomography, X-Ray Computed

We report a case of renal hemangiopericytoma occurring in renal sinus and expanding to the renal hilum. This unusual presentation caused misinterpretation of this tumor as transitional cell carcinoma of the renal pelvis clinically. The patient who was a 30-year-old woman had a relatively well demarcated solid tumor, 8 x 6 cm, in the renal sinus of the left kidney.
Adult ; Case Report ; Female ; Follow-Up Studies ; Hemangiopericytoma/*pathology/radiography ; Human ; Kidney Neoplasms/*pathology/radiography ; Tomography Scanners, X-Ray Computed

OBJECTIVE: To describe computed tomography (CT) features of metastatic gallbladder (GB) tumors (MGTs) from various primary tumors and to determine whether there are differential imaging features of MGTs according to different primary tumors. MATERIALS AND METHODS: Twenty-one patients who had pathologically confirmed MGTs and underwent CT were retrospectively enrolled. Clinical findings including presenting symptoms, type of surgery, and interval between primary and metastatic tumors were recorded. Histologic features of primary tumor and MGTs including depth of invasion were also reviewed. Imaging findings were analyzed for the location and morphology of MGTs, pattern and degree of enhancement, depth of invasion, presence of intact overlying mucosa, and concordance between imaging features of primary and metastatic tumors. Significant differences between the histologies of MGTs and imaging features were determined. RESULTS: The most common primary tumor metastasized to the GB was gastric cancer (n = 8), followed by renal cell carcinoma (n = 4) and hepatocellular carcinoma (n = 3). All MGTs (n = 21) manifested as infiltrative wall thickenings (n = 15) or as polypoid lesions (n = 6) on CT, similar to the features of primary GB cancers. There were significant differences in the morphology of MGTs, enhancement pattern, enhancement degree, and depth of invasion according to the histology of primary tumors (p < 0.05). Metastatic adenocarcinomas of the GB manifested as infiltrative and persistently enhancing wall thickenings, while non-adenocarcinomatous metastases usually manifested as polypoid lesions with early wash-in and wash-out. CONCLUSION: Although CT findings of MGTs are similar to those of primary GB cancer, they are significantly different between the various histologies of primary tumors.
Adenocarcinoma/pathology/radiography/secondary ; Adult ; Aged ; Carcinoma, Hepatocellular/pathology/radiography/secondary ; Carcinoma, Renal Cell/pathology/radiography/secondary ; Carcinoma, Squamous Cell/pathology/radiography/secondary ; Diagnosis, Differential ; Female ; Gallbladder Neoplasms/pathology/*radiography/*secondary ; Humans ; Kidney Neoplasms/pathology ; Liver Neoplasms/pathology ; Male ; Melanoma/pathology/radiography/secondary ; Middle Aged ; Neoplasm Invasiveness/radiography ; Retrospective Studies ; Stomach Neoplasms/pathology ; *Tomography, X-Ray Computed

PURPOSE: To investigate and distinguish the computed tomography (CT) characteristics of chromophobe renal cell carcinoma (chRCC) and renal oncocytoma. MATERIALS AND METHODS: Fifty-one patients with renal oncocytoma and 120 patients with chRCC, diagnosed by surgery between November 2005 and June 2015, were studied retrospectively. Two observers, who were urologists and unaware of the pathological results, reviewed the preoperative CT images. The tumors were evaluated for size, laterality, tumor type (ball or bean pattern), central stellate scar, segmental enhancement inversion, and angular interface pattern and tumor complexity. To accurately analyze the mass-enhancing pattern of renal mass, we measured Hounsfield units (HUs) in each phase and analyzed the mean, maximum, and minimum HU values and standard deviations. RESULTS: There were 51 renal oncocytomas and 120 chRCCs in the study cohort. No differences in clinical and demographic characteristics were observed between the two groups. A central stellate scar and segmental enhancement inversion were more likely in oncocytomas. However, there were no differences in ball-/bean-type categorization, enhancement pattern, and the shape of the interface between the groups. Higher HU values tended to be present in the corticomedullary and nephrogenic phases in oncocytomas than in chRCC. Receiver-operating characteristic curve analysis showed that the presence of a central stellate scar and higher mean HU values in the nephrogenic phase were highly predictive of renal oncocytoma (area under the curve=0.817, p<0.001). CONCLUSIONS: The appearance of a central stellate scar and higher mean HU values in the nephrogenic phase could be useful to distinguish renal oncocytomas from chRCCs.
Adenoma, Oxyphilic/pathology/*radiography ; Carcinoma, Renal Cell/pathology/*radiography ; Diagnosis, Differential ; Female ; Humans ; Kidney Neoplasms/pathology/*radiography ; Male ; Middle Aged ; Retrospective Studies ; Tomography, X-Ray Computed

Paraganglioma is a rare neuroendocrine tumor arising from the undifferentiated cells of the primitive neural crest. We report a case of malignant paraganglioma originating from the left kidney. The 55-year-old female patient was admitted for intractable cough for a month and the presence of a solid mass in the left lung detected by computer tomography (CT). Sonography revealed a mass in the left kidney after admission. Complete surgical resection of the tumor was performed and the diagnosis of malignant paraganglioma originating from the left kidney was established pathologically. During the follow-up for 12 months, the patient showed a good general condition and sonography revealed no evidence of recurrence. Based on these findings, we discussed the diagnosis of this disease using medical imaging modalities.
Female ; Humans ; Kidney Neoplasms ; diagnostic imaging ; pathology ; surgery ; Lung Neoplasms ; diagnostic imaging ; secondary ; Middle Aged ; Paraganglioma ; pathology ; secondary ; surgery ; Radiography

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

The spontaneous regression of metastatic lesions from renal cell carcinoma (RCC) is extremely rare, but may be encountered following cytoreductive treatments. We report a case of a recurrent RCC with multiple metastatic lesions which spontaneously regressed after undergoing radiofrequency ablation of the renal tumor.
Adrenal Gland Neoplasms/radiography/*secondary ; Aged, 80 and over ; Carcinoma, Renal Cell/radiography/*secondary/*surgery ; *Catheter Ablation ; Humans ; Kidney Neoplasms/*pathology/radiography/*surgery ; Lung Neoplasms/radiography/*secondary ; Male ; Neoplasm Recurrence, Local ; Remission, Spontaneous ; Tomography, X-Ray Computed