Cancer Types

The main method for detecting renal pelvis or ureteral cancer is to detect filling defects or occupying lesions in the renal pelvis or ureter through imaging examination, or to detect tumors through pyeloureteroscopy, and then to diagnose them through cytology or pathology (including tumor biopsy or postoperative pathology) examination. The commonly used diagnostic or differential examination methods for renal pelvis and ureteral cancer in clinical practice include routine urine examination to confirm the presence or absence of hematuria. Urinary exfoliative cytology checks for cancer cells in the urine. Of course, cancer cells found in the urine may also come from the bladder and urethra. If cancer cells are found in the urine or pelvic urine during examination, it can diagnose ureteral or pelvic cancer. The imaging examination methods for renal pelvis or ureteral tumors mainly include the following: 1. Ultrasound examination is the most commonly used examination method, which can detect tumors in the renal pelvis or ureter, as well as hydronephrosis in the renal pelvis and ureter, and distinguish between stones and soft tissue lesions. Due to the small size of the ureteral lumen, it is sometimes difficult to detect space occupying lesions in the ureter through abdominal pelvic ultrasound, especially in the lower segment of the ureter. If ultrasound is performed through the rectum or vagina, it is easier to display lesions in the lower segment of the ureter. 2. Excretive urography is one of the basic examination methods for diagnosing renal pelvis or ureteral cancer. Filling defects in the renal pelvis or ureter are a typical manifestation of renal pelvis or ureteral cancer. But attention should be paid to distinguishing it from stones and blood clots. Due to the fact that tumors can cause obstruction in the renal pelvis or ureter, causing the affected side of the kidney to have no function, it can cause the patient's kidney and ureter to not be visualized. When the imaging of excretory urography is poor, it should be combined with retrograde upper urinary tract imaging or other examinations. 3. Retrograde upper urinary tract imaging is a method of examination in which a catheter is inserted into the ureter and renal pelvis through cystoscopy, and contrast agent is injected to enhance the imaging of the upper urinary tract. The advantages of this examination are: ① it is not affected by the patient's renal function or whether they are allergic to iodine containing contrast agents, and the imaging in the renal pelvis and ureter is clearer, especially when there is poor excretory contrast imaging; ② This examination needs to be performed during cystoscopy, which can simultaneously check for tumors in the bladder and observe if there is blood spurting from the affected ureteral opening. If a ureteral tumor protrudes downwards into the bladder from the ureteral opening, it can also be detected; ③ Urine from the affected renal pelvis or ureter can be collected for urine exfoliative cytology examination. 4. CT examination: CT scanning has high resolution, and after plain and enhanced scanning, it can clearly display the location, size, density infiltration range, and relationship between surrounding organs of the lesion. The diagnostic accuracy of renal pelvis tumors can reach over 90%. The typical CT manifestations of renal pelvis and ureteral cancer are: ① soft tissue tumors found in the renal pelvis or ureter, which may be accompanied by hydronephrosis in the pelvis or ureter, as well as infiltration and regional lymph node metastasis around the kidney or ureter; ② After enhancement, the tumor enhancement is not significant. 5. Magnetic resonance imaging (MRI) examination has the advantages of excellent soft tissue contrast and multi axial scanning compared to CT scanning, especially in the diagnosis of renal pelvis cancer and ureteral cancer using MRI urography. 6. Ureteropyeloscopy examination needs to be performed under anesthesia. If the ureteropelvoscopy can be smoothly introduced, it can be seen whether there are tumors in the ureter or renal pelvis, and the diagnosis can be confirmed through brush cytology or biopsy pathology. It can also be treated through ureteropelvoscopy. However, ureteropelvoscopic examination requires anesthesia and may not be able to be smoothly introduced to the lesion site, even posing a risk of ureteral perforation leading to tumor transplantation. Therefore, currently, ureteropelvoscopy is not a routine examination and is usually used when routine imaging examinations cannot provide a clear diagnosis or require visual observation to determine whether surgery to preserve renal function can be performed.