Objective： The aim of our study was to investigate the feature of minimal fat renal angiomyolipoma with sufficient blood supply using CT scans and improve the diagnosis accuracy required to differentiate it from clea...Objective： The aim of our study was to investigate the feature of minimal fat renal angiomyolipoma with sufficient blood supply using CT scans and improve the diagnosis accuracy required to differentiate it from clear cell renal carcinoma. Methods： Retrospective analysis of 24 cases of post-surgery confirmed angiomyolipoma with sufficient blood supply （total of 25 tumors） in our hospital that were used for a pathological comparison study. Results： Among the 24 patients diagnosed with angiomyolipoma, nobody had bloody urine, Of the 96 patients diagnosed with clear cell renal cancer, 14 had bloody urine （14.6%）. In our studied group, the size of angiomyolipomas with sufficient blood supply was between 1.5 cm× 2.0 cm to 8.0 cm× 10.0 cm. During CT scan analysis, twenty tumors had similar density, and five of them had higher density. Only one tumor had a few dots of calcification （4%）. Adipose tissue was not visible in 9 tumors, while 16 tumors had visible dots of adipose tissue, as visualized by CT scan. Intensive scanning indicated that all of the tumors showed a strong enhancement in the renal corticomedullary phase. Twenty tumors had significant heterogeneous enhancement in the early phase, while another set of five cases had homogenous prolonged enhancement. Nineteen patients had surgery to remove the angiomyolipomas, while six patients had single side kidney removal due to misdiagnosis for renal cancer in cases where the tumor severely compromised the renal parenchyma and sinus. All 25 cases were classified as renal angiomyolipoma by pathological analysis. Within the 96 cases of clear cell renal cancer, 64 tumors had relatively low density, 29 tumors had equal density, and 3 cases had relatively higher density. Fourteen of the tumors had calcification （14.6%）, and none of them had visualized adipose tissue. Enhanced CT scans indicated that 69 cases of renal cancer showed significant enhancement in the renal corticomedu^ary phase, which had the abnormal pattern of ＂fast-in-and-fast-out＂. Additionally, 27 cases had slow and prolonged enhancement. Conclusion： Similar to clear cell renal carcinomas, angiomyolipomas with sufficient blood supply also appear to exhibit abnormal enhancement with a pattern of＂fast-in-and-fast-out＂ during the early phase, which is easily misdiagnosed as renal cancer. It is difficult to differentiate them merely through CT scans; the key to differentiating them is to identify the adipose tissue within the tumor. Therefore, it is helpful to use thin-layer CT scans to locate the adipose tissue.展开更多
基金Supported by a grant from Science and Technology Bureau of Guang-zhou, China (No.2004Z3-E0481)
文摘Objective： The aim of our study was to investigate the feature of minimal fat renal angiomyolipoma with sufficient blood supply using CT scans and improve the diagnosis accuracy required to differentiate it from clear cell renal carcinoma. Methods： Retrospective analysis of 24 cases of post-surgery confirmed angiomyolipoma with sufficient blood supply （total of 25 tumors） in our hospital that were used for a pathological comparison study. Results： Among the 24 patients diagnosed with angiomyolipoma, nobody had bloody urine, Of the 96 patients diagnosed with clear cell renal cancer, 14 had bloody urine （14.6%）. In our studied group, the size of angiomyolipomas with sufficient blood supply was between 1.5 cm× 2.0 cm to 8.0 cm× 10.0 cm. During CT scan analysis, twenty tumors had similar density, and five of them had higher density. Only one tumor had a few dots of calcification （4%）. Adipose tissue was not visible in 9 tumors, while 16 tumors had visible dots of adipose tissue, as visualized by CT scan. Intensive scanning indicated that all of the tumors showed a strong enhancement in the renal corticomedullary phase. Twenty tumors had significant heterogeneous enhancement in the early phase, while another set of five cases had homogenous prolonged enhancement. Nineteen patients had surgery to remove the angiomyolipomas, while six patients had single side kidney removal due to misdiagnosis for renal cancer in cases where the tumor severely compromised the renal parenchyma and sinus. All 25 cases were classified as renal angiomyolipoma by pathological analysis. Within the 96 cases of clear cell renal cancer, 64 tumors had relatively low density, 29 tumors had equal density, and 3 cases had relatively higher density. Fourteen of the tumors had calcification （14.6%）, and none of them had visualized adipose tissue. Enhanced CT scans indicated that 69 cases of renal cancer showed significant enhancement in the renal corticomedu^ary phase, which had the abnormal pattern of ＂fast-in-and-fast-out＂. Additionally, 27 cases had slow and prolonged enhancement. Conclusion： Similar to clear cell renal carcinomas, angiomyolipomas with sufficient blood supply also appear to exhibit abnormal enhancement with a pattern of＂fast-in-and-fast-out＂ during the early phase, which is easily misdiagnosed as renal cancer. It is difficult to differentiate them merely through CT scans; the key to differentiating them is to identify the adipose tissue within the tumor. Therefore, it is helpful to use thin-layer CT scans to locate the adipose tissue.
