Kidney cancer can also be misdiagnosed because the current primary means of diagnosing kidney cancer relies on imaging tests such as CT (computed tomography) and MRI (magnetic resonance imaging), which usually have a diagnostic rate of about 90%, leaving about 10% of patients with an occupied kidney without clarity about the exact nature of the disease. Kidney cancer needs to be differentiated from these diseases:
Renal cysts
Renal cysts are the most common renal occupying lesions, and simple renal cysts are a benign condition. However, in cases of irregular thickening of the cyst wall, or bleeding within the cyst, or separation of the cyst wall, attention needs to be paid and further CT or magnetic resonance imaging (MRI) needs to be done to rule out cystic kidney cancer.
Renal malformation tumor
Renal malformation tumor, also called vascular smooth muscle lipoma, is a relatively common benign tumor. Sometimes we encounter atypical renal malformations with very little fat content, which are difficult to differentiate from kidney cancer and often require further CT and MRI to diagnose, and in some patients, the only way to differentiate from kidney cancer is through pathological examination after surgery.
Kidney abscess
Patients with renal abscesses have symptoms of infection and fever, often with purulent urine and high blood levels, and need to be identified by bacterial cultures and puncture tests.
Renal lymphoma
Relatively rare, lacking specificity on imaging, mostly nodular or diffusely infiltrating the entire kidney, with a markedly enlarged renal appearance, often with infiltration of retroperitoneal lymph nodes, mostly localized to systemic lymphoma.
Yellow granuloma of the kidney
Also very rare, this is a specific type of chronic infection of the renal parenchyma.
Renal pelvic carcinoma
Pelvic carcinoma is a malignant tumor arising in the mucosa of the renal pelvis and calyces. It tends to present with hematuria in the early stages and can be detected by CT, CTU (CT urography) as an occupying lesion in the renal pelvis or as a significant filling defect, often with positive urine exfoliative cytology or urine nuclear matrix protein.