The most common histologic type of renal cell carcinoma is clear cell carcinoma, which accounts for approximately 70-80% of renal cell carcinomas. Under the microscope, the cytoplasm of these tumor cells is relatively rich and contains abundant substances such as glycogen, phosphate and neutral fat. These substances are dissolved during the section making process, thus giving the cells a transparent appearance, hence the name clear cell carcinoma. As the malignancy of clear cell carcinoma increases, the fat content within the cytoplasm gradually decreases, and there may even be obvious cellular anisotropy and nuclear schizophrenia. Mutations in the VHL gene can be found in approximately 75% of patients with clear cell carcinoma. In addition to clear cell carcinoma, renal cell carcinoma also contains other histopathological types such as papillary carcinoma, suspicious cell carcinoma, collecting duct carcinoma, and undifferentiated carcinoma.