ABSTRACT
@#This is a case of 27-year-old female who presented with a slow growing mass on the right flank. Computed tomography scan was done which revealed a cystic mass with septations and peripheral calcifications. Radical nephrectomy was performed on the patient. Histopathology and immunohistochemical staining were done which revealed features consistent with metanephric adenoma.
ABSTRACT
Objective To investigate the performance of MSCT in the diagnosis of metanephric adenoma.Methods The imaging data of 5 cases of metanephric adenoma confirmed by operation and pathology in our hospital were collected and analyzed retrospectively.The location, size, shape, density and enhancement of the lesion were further retrospectively analyzed.Results In the incorporated 5 cases of metanephric adenoma, the male to female ratio of cases was 1:4, all were unilateral, including 2 cases of the right kidney,3 cases of the left kidney,2 cases were located in the upper pole, 2 cases in the polar region, 1 case in the lower pole of the kidney.Maximum diameter of the metanephric adenoma ranged from 2.9 cm to 8.4 cm, with an average value of 4.8 cm.The shape of metanephric adenoma was classified into: round (3 cases) and oval (2 cases).On plain scanning slightly lower density was found in 2 cases, equidensity in 2 cases and slightly higher density in 1 case.Furthermore,1 case had small punctatel calcification in the edge of the lesion,1 case with renal papillary carcinoma.4 cases underwent plain and enhanced scanning,and 1 case plain scanning,in which slight density increase after intravenous enhancement was showed in 3 cases,moderate enhancement in 1 case,more uniform enhancement in 3 cases,uneven enhancement in 1 case,delayed enhancement in 4 cases.Conclusion The characteristic MSCT features of metanephric adenoma have a certain specificity.Preoperative correct understanding is helpful to guide the operation scheme.
ABSTRACT
Objective To explore the clinical and histopathological features of metanephric adenoma (MA). MethodsClinical and pathological data of 10 cases of MA were analyzed retrospectively.There were 4 males and 6 females,aged from 33 to 65 years,with an average of 45 years.2 patients had flank pain,4 patients had gross hematuria,and 4 patients were found by physical examination.The average diameter of tumor was 4.5 cm (2.5 - 8.0 cm).All patients were diagnosed as renal tumor by CT scan.9 patients underwent radical nephrectomy and 1 patient underwent partial nephrectomy. Results Pathological examination found that the tumors are composed of densely packed small uniform cells with regular nuclei that formed a tubular or adenoid pattern.Mitotic figures were absent or rare.4 patients were diagnosed as MA,2 cases were diagnosed as low-grade malignant MA,and 4 cases were diagnosed as MA with malignant component (2 cases of adenocarcinoma,1 case of chromophobe cell carcinoma,and 1 case of well differentiated papillary adenocarcinoma),7 cases were followed up for 22 months ( 10 to 34 months) without recurrence or metastasis. Conclusions MA is very rare benign renal tumor originating from epithelium,and a few are malignant,and some may contain malignant ingredients.Nephron-sparing surgery and radical nephrectomy are eligible for the treatment of MA.Considering the uncertainty of the biological behavior and cellular origin of MA,a long-term follow-up is necessary.
ABSTRACT
Metanephric adenoma is a rare renal epithelial tumor. Its light microscopic features are very characteristic, and immunohistochemical and electron microscopic studies are not critical to the diagnosis. The literature indicate that, to date, the tumor has behaved in a benign fashion, and predominantly but not exclusively occurred in middle-aged women. It occurs in a wide range up to 11 cm and is usually an incidental finding but may be symptomatic with hematuria or flank pain. Recently, we have experienced a case of renal tumor showing distinctive adenomatous features, which is incidentally found in a 52-year-old female. This tumor is confined to the renal cortex and is well-circumscribed with a characteristic uniform and orderly proliferation of compact well-differentiated small tubules lined by bland oval cells with a very low level of mitotic activity. The term metanephric adenoma is appropriate for this tumor because it accurately describes its bland proliferation of tubules and reflects the embryonic architectural and cytological appearance of this proliferation. The pattern of the tumor, with its occasional papillary glomeruloid- like bodies and foci of elongated tubules, is reminiscent of the fetal metanephric kidney.