What Is a Urothelial Neoplasm?

Upper urothelial tumors are rare, and foreign reports of renal pelvis tumors account for about 10% of all renal tumors and 5% of all urothelial tumors. Bilateral tumors are rare, and upper urothelial tumors occur at the same time or successively, accounting for 2% to 5%. The ureteral tumor is only a quarter of the pelvic tumor. Domestic reports of renal pelvis cancer account for 24% to 26% of renal tumors. The male to female ratio is 3: 1, aged 17 to 80 years, with an average of 56.4 years.

Epithelial tumor

Overview of upper urothelial tumors

The cause of upper urothelial cancer is similar to that of bladder cancer. Smoking and occupational carcinogens are important factors. Genetic defects have been attracting more and more attention under the influence of external factors. Regional and ethnic diseases such as "Balkan Nephropathy" may be related to genetic and environmental factors.

Transitional epithelial cancer of the upper urinary tract can infiltrate the parenchyma and surrounding structures of the kidney along the epithelium and spread along the lymph or blood line. The higher the level of the tumor, the greater the tendency to spread. Domestic and foreign data show that the tumor spreads along the epithelium from top to bottom, and pre-cancerous lesions such as carcinoma in situ or dysplasia often exist around the tumor and the ureter. Bottom-up expanders often have bladder ureteral reflux. Lymphatic metastasis depends on the location of the primary cancer, metastasis to the ipsilateral large vessels, common iliac vessels, and pelvic lymph nodes. Renal pelvis cancer can extend into the renal vein and vena cava. Common sites of blood circulation are liver, lung, and bone.

Key points for diagnosis of upper urothelial tumors

Typing and staging

Tumor classification and staging are often used as indicators for selecting treatment methods and estimating prognosis. 83% of patients reported in foreign countries match the classification and staging, of which staging is a more reliable indicator of prognosis.

The clinically used TNM staging system standards are as follows:

Tis: carcinoma in situ;

Ta: confined to the mucosa, usually papillary;

T1 invades the submucosa;

T2: invade the muscular layer;

T3: Invasion of tissues around the renal pelvis and ureter or invasion of renal parenchyma;

T4: Violation of adjacent organs or structures;

N1: 1 lymph node metastasis, diameter 2cm;

N2: 1 lymph node metastasis, 2 ~ 5cm in diameter or multiple lymph node metastases, diameter <5cm;

N3: metastatic lymph node diameter> 5cm;

M1: hematogenous metastasis or distant lymph node metastasis.

T3 stage renal pelvic cancer has a better prognosis than T3 stage ureteral cancer because the renal parenchyma can serve as a barrier to prevent further spread. For years, scholars have tried to find molecular markers related to prognosis. DNA ploidy analysis of ABH antigen, T antigen, and flow cytometry is not reliable in assessing prognosis. P53 gene mutation has practical value in predicting the occurrence and development of bladder cancer, but the prediction of the biological behavior of upper urothelial carcinoma is not accurate. To date, the prognosis of patients with upper urothelial carcinoma still depends on clinical and histological indicators (grading, staging, tissue morphology, size, and number).

Clinical manifestations of upper urothelial tumors

1. Gross hematuria with intermittent hematuria is the most common symptom (40% to 70%), and manifests a full course of hematuria, accompanied by strips of blood clots. Microscopic hematuria can be detected in almost all patients.

2. About one-third of patients with low back pain complain of dull pain in the lower back, which is caused by upper urinary tract obstruction and dilation. Blood clots passing through the ureter can cause renal colic. About 10% to 15% of the patients have no special symptoms, and the upper urinary tract tumor was found only when imaging was performed for other reasons. A small number of patients seek medical treatment due to abdominal, lumbar mass, weight loss, anorexia and other symptoms.

Laboratory test of upper urothelial tumor

1. Urinary cytology is less accurate for cytological examination of the excreted urine, and most tumors with low "grade" tumors are not found abnormally. The positive rate increases with the "grade" of the tumor. Repeated rinsing with normal saline after intubation of the ureter and collection of reflux fluid for cytological examination can improve the diagnosis rate. However, if specimens are taken after retrograde urography, there can be false positive results due to the influence of high concentration contrast agents. A catheter with a small brush at the end is inserted into the lesion, and the tissue is brushed back and forth for pathological examination, which can improve the accuracy.

Imaging examination of upper urothelial tumors

1. Urography: Intravenous urography usually shows irregular filling defects and is connected to the wall of the tube.

When severe obstruction occurs, the upper urinary tract is dilated, and the contrast agent density is reduced or not developed. Care must be taken to observe the contralateral upper urinary tract and bladder for lesions. Poor imaging can be performed retrograde upper urography, and wash fluid for cytological examination.

2. B-ultrasound: The pyelogram shows lesions with filling defects. B-ultrasound can be used to distinguish tumors or stones.

3 CT examination: CT examination will ignore the diagnosis of small tumors. Larger tumors were shown as soft tissue dense images with an average CT value of 46 HU (10 to 70 HU). CT value did not increase after intravenous contrast injection. CT examination can also show the pathological changes when the renal function is poor, it can distinguish the renal pelvis tumor and renal tumor, and can know whether the tumor has infiltration, which is helpful for staging. More valuable than MRI.

Other tests for upper urothelial tumors

1. Patients who have not been diagnosed with endoscopic imaging can have a smaller lesion on the uretero-pyeloscope on the side where hematuria does occur. Soft ureteroscopy can reach each kidney, but the field of view is small. Even if the irrigation is continued, sometimes the observation is not satisfactory. Using biopsy forceps to extract tissue through endoscopic forceps for pathological examination can help diagnosis, but the tissue mass is small and must be analyzed in conjunction with urine cytology and other test results to confirm the diagnosis. Cystoscopy should be observed for tumors in the bladder. If necessary, samples of living tissues are taken for examination to understand whether there is cancer in situ or precancerous lesions.

Upper urothelial tumor treatment

The traditional treatment for upper urothelial cancer is open renal and ureteral resection. With the advancement of endourology, there are less invasive or more palliative surgical methods, including laparoscopic kidney, total ureterectomy, ureteroscopy or percutaneous endoscopic surgery. In general, palliative or radical surgery is effective for well-differentiated, low-stage tumors; radical resection is better for moderate-differentiated tumors; and the prognosis of poorly-differentiated, high-stage tumors is poor.

1. Total nephrectomy is still the gold standard for the treatment of upper urothelial carcinoma, and it is suitable for most patients. Due to renal and partial ureterectomy, the recurrence rate of ureteral stump tumors reached 30% to 35%. Therefore, the bladder mucosa around the ureter and the orifice is removed at the same time during application. Regardless of the operation performed through one or two incisions, except for low-grade tumors, it is not advisable to cut off the ureter during operation to prevent cancer cells from scattering and contaminating the surgical field. Generally free kidney ureter is excised through lumbar or epigastric incision, but not temporarily cut off. Another lower abdominal incision was made and the ureter was ligated, then the bladder was cut, and the ureter and the bladder mucosa around the orifice were separated and excised.

The method for total ureteral resection of the kidney and ureter through an incision is to first cut the ureteral bladder wall and the surrounding bladder mucosa through a urethral resection microscope, and then place the urethral catheter. Then a lumbar or abdominal incision is made. After the ureter is ligated on the distal side of the tumor, the kidney is removed, the ureter is freed distally, and the last segment is pulled out.

The grade of urothelial cancer is high (moderate or low differentiation), and lymph node metastasis has often occurred. When performing a standard radical resection, lymph nodes near the ipsilateral great vessels, the common common iliac artery, and the pelvic vessels should be extensively removed at the same time.

Pan Bonian et al. Reported 107 patients with total renal ureterectomy. Recurrence of bladder cancer accounted for 16%. The 3, 5 and 10-year survival rates were 75.61%, 60.19% and 45.35%. Batata reported that the 5-year survival rate after total ureterectomy was 91% at Tis, Ta or T1, 43% at T2, 23% at T3 or T4, N1 or N2, and 0 at N3 or M1. For young patients with high-grade, high-stage tumors and normal upper urinary tract, it is best to perform open renal ureterectomy and lymphadenectomy. Open surgery for resection of the renal pelvis tumor or partial nephrectomy, the recurrence rate is as high as 38% to 60%, so it is not recommended. Solitary kidney or bilateral upper urothelial carcinoma, in addition to the choice of intracavitary resection, palliative surgery or local chemotherapy, for radical nephrectomy, regular hemodialysis after surgery, kidney transplantation at an appropriate time, Still optional.

2. Laparoscopic total nephroureterectomy with laparoscopic total nephrectomy for laparoscopic nephrectomy can achieve the goal of radical cure, fewer complications, and quick recovery after surgery. The follow-up of 53 cases reported in comprehensive literature for a maximum of 2 years, of which 10 cases were removed by subumbilical incision of the lower ureter, and 18 cases were separated by urethra and closed the ureteric bladder wall. Then remove the kidney under laparoscopy, free the ureter all the way, raise the lower part to make the bladder wall tent-like, close the bladder hole with a metal clip, cut the ureter, and make a small abdominal wall incision to remove the specimen. The average operation time was 2.6 ~ 7.7h, and the average hospital stay was 3.6 ~ 9d.

Compared with open renal ureterectomy, this method has fewer pulmonary complications, shorter hospital stay, and faster recovery. The cancer-specific survival rate is similar to that of open surgery, and the metastasis rate and lower urinary tract recurrence rate are also similar, but the local recurrence rate is higher than that of open surgery.

3 Percutaneous endoscopic surgery authors use endoscopic transdermal channels to treat renal pelvis and calamary epithelial tumors. Endoscopes with larger calibers, wider working channels, and better visibility are used for surgery. For tumors growing in the kidney, the percutaneous approach is easier to reach the tumor site than the ureter. The disadvantage is that the integrity of the urinary tract is destroyed, and cancer cells can leak from the percutaneous channel. There has been one case of cancer vaccination. Jabbour et al. Reported that 61 patients with superficial urinary tract epithelial cancer were treated with skin. A No. 24 nephroscope and a neodymium-YAG laser were used to cauterize the tumor. Thirteen patients received BCG perfusion. During a follow-up of 48 months (9 months to 12 years), the overall cancer-specific survival rate was 95%, of which Ta was 100% and T1 was 80%. No fistula cancer vaccination. This method is considered to be safe and effective with few complications. For patients with good health and normal contralateral kidneys, percutaneous treatment is an optional treatment.

4 Ureteroscopic surgery for urothelial carcinoma with ureteroscopy is suitable for small lesions with low grade and easy access. Resection and coagulation of tumors and pedicles. The neodymium YAG laser has a tissue depth of 5-6mm, which is suitable for the treatment of renal pelvis tumors and has a low recurrence rate. Using a holmium laser, the tissue depth is 0.5mm, which is more suitable for superficial resection and coagulation of small tumors. The local recurrence rate after ureteral surgery is 14% to 40%, and the ureteral stenosis rate ranges from 4.9% to 13.6%. Recently, Hendin et al. Reported that 96 patients with upper urothelial carcinoma underwent ureteroscopy before radical surgery. The long-term effect and cancer-specific survival rate were similar to the results of standard surgery. The cancer cells flow into the lymphatic vessels or blood vessel spaces, causing them to spread during the operation.

5. Drug infusion therapy has been reported in the literature with mitomycin C infusion in patients with lower ureteral cancer and bladder ureteral reflux. After the tumor is removed, the use of titipide or BCG for upper urinary tract perfusion treatment and perfusion therapy for upper urinary tract carcinoma in situ can also achieve some effects. However, some patients are complicated by sepsis, renal pelvis, ureter scar formation and obstruction, and systemic toxicity caused by drug absorption. Although few serious complications have been reported, the safety of this therapy is questionable. This method may be most suitable for patients with multiple superficial tumors of the upper urinary tract or carcinoma in situ, poor renal function or bilateral tumors. Drug infusion should be performed through nephrostomy tube, and retrograde perfusion method should not be used.

6. Other treatments for urothelial carcinoma are rarely reported in the literature, and the efficacy has not been determined. It may be effective as an adjuvant therapy for poorly differentiated or invasive cancer, and may be effective in reducing pain caused by bone metastatic cancer.

The long-term treatment of M-VAC for systemic chemotherapy is very ineffective, with many serious side effects, and is not widely used. Selective arterial embolization for advanced renal pelvic cancer has only a short-term effect.