Everything in the world must take its place according to a certain order of rules —— Lemont
Renal pelvic cancer is mainly a uroepithelial tumor, which is relatively difficult to diagnose. In recent years, medical disputes often arise due to renal pelvic cancer, mostly due to doctors’ unclear preoperative diagnosis and mistaken removal of the kidney, and this article describes the treatment process of such diseases with a specific example.
The patient was a 62-year-old female who was admitted to the hospital mainly because of intermittent painless carnal hematuria for six months.
Hematuria is the most common clinical symptom of tumor of urinary tract collecting system, including carnaroscopic and microscopic hematuria, and generally the patient has no discomfort except for hematuria. About 1/2 of the patients with carnal hematuria are eventually diagnosed with uroepithelial tumor. Microscopic hematuria is firstly observed by urine phase contrast microscopy to clarify the site of bleeding, and the majority of normal red blood cells indicate bleeding in the collecting system of the kidney.
The patient brought ultrasound and CT to the outpatient clinic. Ultrasound described: right renal pelvis occupancy, size 1×1cm, abdominopelvic CT scan showed: hypodense mass of about 1.5×1cm in the right renal pelvis.
My consideration: 1. Possible occupancy in the right renal pelvis
2. Hematuria may be related to the occupancy in the right renal pelvis
3. The nature of the occupancy in the right renal pelvis is unknown (benign – stone, polyp, blood clot? (malignant?)
4. Whether there are problems in other parts of the urinary system
Ultrasound is of limited value in the diagnosis of upper urinary tract tumors, with a positive diagnostic rate of about 60%. It presents as a hypoechoic mass that can be differentiated from a negative stone (strong echogenicity) in the renal pelvis. The average CT value of uroepithelial carcinoma is between 45Hu (10-70Hu). The positive diagnostic rate of CT for renal pelvis carcinoma can reach 80%, especially the differential diagnosis with intrapelvic stones has higher specificity and can be used for the diagnosis and staging of renal pelvic carcinoma, but in clinical practice, smaller intrapelvic tumors are difficult to show because the renal pelvis or calyces are not dilated.
The renal pelvis, ureter, bladder and urethra of the urinary system are covered with uroepithelium, which are anatomically both continuous and separate organs. The urinary epithelium is in contact with urine, and if there are carcinogenic substances in urine, it can cause tumors in any part of the urinary epithelium, so there is a multi-organ pathogenesis problem in uroepithelial cancer. Some literature reports that the incidence of tumors in other parts of one side of the renal pelvis is 53%. In clinical practice, although there are not so many, the problem of multi-organ pathogenesis should not be underestimated.
My treatment: 1. Urological ultrasound: A hypoechoic reflective area with poorly defined boundaries and echogenic heterogeneity was seen in the right renal pelvis: 3.0×1.2 cm.
2. Urological MRI+MRU: an ovoid mass with a size of 2.5×2.3×1.9 cm was seen in the right renal pelvis with moderate signal in T1 and T2, and MRU showed a filling defect in the right renal pelvis. (As shown in Figures 2 and 3)
3. intravenous urography showed a mass in the right upper and middle pole renal calyces area.
4. cystoscopy showed no significant abnormalities in the bladder.
5. The above examinations did not show any significant abnormalities in other parts of the urinary system except the right renal pelvis.
MRI does not have any advantage over CT in the diagnosis of renal pelvis cancer, but MRU can replace intravenous pyelogram to observe the presence of filling defects in the urinary tract, especially when there are obstructive lesions in the urinary tract.
Figure 2
Figure 2
Filling defect in the renal pelvis
Figure 3 MRU showing filling defect and ureteral tortuosity
Intravenous pyelogram is the classic method to diagnose urological upper urinary tract tumors, but with the advancement of medical imaging equipment, it is gradually replaced by MRU or CTU. In addition to further clarifying the diagnosis, this test is also performed to understand the function of the contralateral kidney. It is common sense to understand the function of the contralateral kidney before removing one kidney in clinical practice. Of course, renal hemogram can be performed, but it cannot observe the renal calyces and ureters.
With the above tests, the diagnosis of right renal pelvis tumor should be positive, but I still have doubts whether it is a blood clot. As a matter of fact, regardless of other things, it has been about 15 days from the time of the external examination to the completion of the examination in our hospital, so if it was a blood clot, it should have dissolved. To be on the safe side, I had another ultrasound the day before the surgery, which seemed a bit redundant and cumbersome, but on the other hand, wasn’t it more foolproof?
The diagnosis of the right renal pelvis mass was clear, benign or malignant?
All 3 urine cytology tests were negative. The positive rate of urine exfoliation cytology in the diagnosis of bladder cancer is around 30%, and the positive rate of cytology for upper urinary tract tumors is lower than that of bladder cancer. In addition, urinary tumor markers such as NMP-22 and other molecular tumor markers that emerged with the progress of molecular biology have a high rate of positive diagnosis and false positive rate due to the great interference by external factors, and many units that have carried out such tests have a tendency to gradually abandon them.
Ureteroscopy, ureteroscopy is the most direct means of diagnosing renal pelvis tumor. It has been reported that the diagnostic accuracy of renal pelvis cancer is 87%, which is directly related to the operation level of the operator. In this case, from the intravenous pyelogram, there was a distortion of the ureter below the pelvic ureteral junction (as shown in Figure 3 MRU), and it was feared that the renal pelvis could not be observed.
What else can the physician do in terms of the diagnosis of this patient? The family was told to perform ureteroscopy and, if successful, to obtain frozen pathology, followed by laparoscopic radical pelvic cancer + lower abdominal incision for extraperitoneal resection of the lower ureter and bladder wall segment and part of the bladder. If it is not successful, can the family accept radical surgery? After repeatedly explaining the difficulty of determining the diagnosis, the family readily accepted.
Under anesthesia, the ureteroscopy was performed in an amputated position. Consistent with preoperative expectations, the ureteroscope was obstructed from reaching the ureteral torsion and the tumor in the renal pelvis could not be observed. It was explained to the family and agreed to be treated as radical surgery for renal pelvis cancer.
At this point, if the tumor in the renal pelvis was really benign, I would have no regrets, and the patient and his family would understand my hard work and good intentions.
The surgery continued in the expected manner, with the patient in the lithotomy position to the lateral position, and the radical resection of the renal pelvis under the retropubic laparoscope. The ureter was found before resection, and a titanium clip was applied to prevent the tumor from growing in the bladder. The right lower abdominal inverted figure-of-eight incision was made and the kidney was removed from the renal fossa, and the inferior ureter and bladder wall segment and bladder were partially resected extraperitoneally. (There are many surgical options for lower ureteral and bladder wall segment and partial bladder resection, but I prefer this one for reasons to be described in another article)
The procedure went smoothly and took 4 hours, including the time for position change and anesthesia.
First, because pelvic cancer is more prone to lymph node metastasis in the hilar region, radical surgery for pelvic cancer is more rigorous than for renal cancer, with resection outside the Gerota fascia and removal of fat in the hilar region. Secondly, the bladder wall segment and part of the bladder around the ureteral orifice should be resected. It would be very difficult to diagnose the residual bladder wall segment and the lower segment if tumors appear locally. In this case, the surgery was performed strictly according to the above criteria. (Gross specimen drawing)
Partial bladder
perirenal fat
renal pelvis mass
Postoperative pathological gross specimen (Figure 4): the size of the right nephrectomy specimen sent for examination was 10×6×4 cm, the ureter was 22 cm long and 0.5 cm in diameter, the mucosa of the ureter was smooth, and a cauliflower-like mass of 2.5×2.5×2 cm was seen in the renal pelvis, filling the pelvis, and part of the bladder tissue was 1.5×1.5 cm with a smoother mucosa.
Pathological diagnosis: (renal pelvis) moderate-low differentiated uroepithelial carcinoma without involvement of renal cortex, bladder (-), bladder dissection (-), renal fat capsule (-), ureter (-).
The surgical procedure of this patient ended perfectly.