Renal cancer origins
Renal cancer originates from renal tubular epithelial cells and can occur in any part of the renal parenchyma, but it is most common in the upper and lower parts, and a few cases invade the entire kidney. The left and right kidneys have equal chances of developing the disease, and bilateral lesions account for 1% to 2%.
Because the kidneys are hidden deep inside the human body, there are many imaging examination methods, and preoperative diagnosis is usually not difficult. However, misdiagnosis and mistreatment still occur from time to time, so attention must be paid.
Diseases that are easily confused with renal cancer
1. Renal cysts
Typical renal cysts are easily distinguished from renal cancer from imaging examinations, but when there is bleeding or infection in the cysts, they are often easily misdiagnosed as tumors. Some renal clear cell carcinomas are uniform inside and have very weak low echoes, which are easily misdiagnosed as very common renal cysts during physical examination screening.
For benign renal cysts with irregular thickening of the cyst wall and high central density, it is difficult to distinguish them using any of the above examination methods alone. It often requires comprehensive analysis and judgment, and if necessary, a puncture biopsy can be performed under the guidance of B-ultrasound. It is not advisable to easily give up follow-up or perform surgery rashly.
2. Renal hamartoma
It is a common benign renal tumor. Due to the presence of fat components, it can be qualitatively diagnosed on B-ultrasound, CT and MRI images, and it is easy to distinguish it from renal cell carcinoma clinically.
The key to distinguishing renal cancer from renal hamartoma is that there is no fat tissue in renal cancer, but there is fat tissue in hamartoma. However, in a few cases, renal cell carcinoma tissue may also contain fat tissue, which may cause misdiagnosis. In addition, it is not uncommon for hamartomas with little fat components to be misdiagnosed as renal cancer.
3. Renal lymphoma
Renal lymphoma is rare. Visceral lymphoma lacks imaging characteristics, presenting multiple nodules or diffuse moist kidneys, which enlarges the kidney shape. Retroperitoneal lymph nodes are often affected.
4. Renal xanthogranuloma
It is a rare special type of severe chronic renal parenchymal infection.
There are two morphological manifestations: one is diffuse type, with enlarged kidney volume, abnormal morphology, and disordered internal structure, which is not easy to be confused with tumors. The other is focal, with localized solid nodular echoes in the kidneys, which lack specificity and are sometimes difficult to distinguish from tumors.
However, these patients generally have symptoms of infection, tender masses in the kidney area, and a large number of white blood cells or pus cells in the urine. As long as careful observation is made, differential diagnosis is not difficult.