Objective To investigate the clinical characteristics of adult Wilms'tumor in Chinese adults and to improve the recognition of adult Wilms'tumor.Methods The clinical data of 6 Wilms'tumor patients treated in our hospital were reviewed. Of them, there were 4 male patients and 2 female patients with mean age of 31 years old. Four patients with abdominal and flank pain and 2 patients with abdominal masses were the main clinical manifestations. One case accompanied with hematuria and another one had fever.Tumor masses were palpable by physical examination in 4 patients. Five patients had percussion tenderness over kidney region and 1 case had abdominal tenderness. Six cases underwent urinalysis and red blood cell was positive in 2 cases. There were no abnormal results in other laboratory tests. Chest X-ray was routinely performed before operation. Six patients underwent ultrasonography and all showed hypoechoic masses (5.0cm×5.0 cm-22.0 cm×25.0 cm) with clear margin. Four cases examined by CT and all had solid masses with inhomogeneous density and clear margin. On enhanced CT scan, 1 of 4 cases demonstrated irregular enhancement of the mass with local hemorrhagic necrosis area. The CT value ranged from 11-40 HU, with an average value of 22.5 HU, and increased to 35-78 HU, with an average value of 63.5 HU after administration of contrast. Two cases of MRI revealed solid mass defects.Three cases underwent IVU examination and showed the enlargement of renal umbra as well as thinning of renal calices caused by the compression of tumor and 1 case showed hydronephrosis.Thus, 5 cases were diagnosed with renal tumor and 1 case was diagnosed with cavitas pelvis tumor before operation. Five patients successfully underwent nephrectomies and 1 patient accepted oophorotomy with no subsequent complication.Retroperitoneal lymph node dissection(RPLND) was performed at the time of radical nephrectomy or oophorotomy in all patients. The tumor was found to be about 5-25 cm in size during operation. One of the tumors had invaded pancreas tail, one had invaded to the lateral abdominal wall and one had invaded into the inferior caval vein. Renal hilar lymph node was found to be exceeded 1.5 cm×1.5 cm in 2 patients. The post-operative incisal surface of the tumor presented with gray-yellow color. Capsule was intact in 4 patients. Three cases had hemorrhagic necrosis in tumor center. All the specimens sent for the pathological examination. None received adjuvant therapy before operation. Four patients received chemotherapy plus radiotherapy after surgery and other 2 patients received chemotherapy only. All patients were followed up with routine lab tests, ultrasonography and chest X-ray.Results Six patients were staged according to the National Wilms'Tumor Study staging system as follows: 1 case in stage Ⅰ, 2 cases in stageⅡ, 2 cases in stage Ⅲ and 1 case in stage Ⅳ. Nephrectomies or oophorotomy were performed in all patients successfully. Tumor diameters were from 4.5-25.0 cm, in average 11.8 cm.All cases had pathological diagnosis of Wilm's tumor. Five cases were classified into favorable histologic type and 1 case was in unfavorable histologic type. Two patients with lymph node metastasis and 3 patients with local invasion were observed. One patient with pulmonary metastasis was recorded. Six patients were followed up for 1-7 years. Five patients survived with no evidence of cancer recurrence. One patient died of pulmonary metastasis 2 years after surgery.Conclusions The majority of adult Wilms'tumors are found with local invasion and metastasis. The incidence of hematogenous metastasis in adult Wilms'tumor is higher than other types of renal tumor as well. The early diagnosis and radical surgical treatment and adjuvant chemoradiotherapy could improve the survival rate.

Objective To review the pathogenesis, pathology, diagnosis and prognosis of calci-fication or ossification renal cell carcinoma with 1 case report. Methods A 48-year-old man was re-ferred for evaluation of an incidental mass found on the upper-middle right kidney, and computed tomography showed a 7 cm tumor with extensively calcification. PET-CT found an extensively calci-fied and ossification mass without high-function in the upper-middle right kidney. Under the diagnosis of renal cell carcinoma, a transabdominal radical right nephrectomy was performed. Results During the operation, a 7.5 crux 5.0 cm well-circumscribed, encapsulated heterogeneous mass was found on the upper-middle right kidney. The patient underwent an partial nephrectomy. Frozen section diagno-sis was renal cell carcinoma with heterotopic bone formation. Then a transabdominal radical right ne-phrectomy plus regional lymph node dissection were performed. Paraffin sections showed renal cell carcinoma with heterotopic bone formation(clear cell carcinoma, pT2b No M0 ). There was neither me-tastasis nor recurrence during the 8 months follow-up. Conclusions Renal cell carcinoma with ossifi-cation is extremely rare. Renal mass with obvious substantive calcification ossification should be trea-ted as malignant mass before operation. The prognosis of renal cell carcinoma associated with ossifica-tion is relatively good.