OVERVIEW

What is renal pelvis cancer?

Renal pelvis cancer (carcinoma of renal pelvis) refers to a malignant tumor originating in the renal pelvis, which is a part of the kidney. Since the renal pelvis is composed of different types of cells, renal pelvis cancer can also be classified into different types. 90% of renal pelvis cancers are urothelial carcinomas, 8% are squamous cell carcinomas, and the remaining are adenocarcinomas.

In the early stages, renal pelvis cancer may present as painless hematuria, while in advanced stages, symptoms such as weight loss, anemia, and abdominal masses may occur.

For localized renal pelvis cancer, surgery is the only potentially curative treatment. For advanced cases with extensive lesions or metastasis, surgery is no longer an option, and chemotherapy may be administered, though the efficacy is not always satisfactory. Radiation therapy has poor effectiveness against renal pelvis cancer.

Is renal pelvis cancer common?

Renal pelvis cancer is rare and most commonly occurs in middle-aged and elderly individuals between 40 and 70 years old, with a male-to-female patient ratio of approximately 2:1.

SYMPTOMS

What are the symptoms of renal pelvic cancer?

• Early stage: Most patients experience intermittent, painless hematuria. Some may also have lower back pain, while a small number may present with frequent urination, urgency, or dysuria.
• Advanced stage: Patients may exhibit symptoms such as weight loss, anemia, weakness, lower limb edema, abdominal masses, and bone pain.

What diseases can renal pelvic cancer cause?

• Blood clots may lead to renal colic (severe lower back pain).
• Cancer cells from the renal pelvis may travel downstream with urine and implant in the bladder, potentially causing bladder cancer.
• Advanced stages may result in cachexia (weight loss, anemia, weakness), renal failure, and abdominal or bone metastases.

Can renal pelvic cancer leave sequelae?

Possible sequelae include incisional hernias, renal insufficiency, or damage to surrounding organs caused by surgery.

CAUSES

What causes renal pelvic cancer?

The exact cause of renal pelvic cancer remains unclear, but it is currently believed to be associated with the following factors:

• Balkan nephropathy: Primarily occurring in the Balkan region (Bulgaria, Greece, Romania, and former Yugoslavia), individuals with a family history of Balkan nephropathy have a risk of developing renal pelvic cancer that is 100 times higher than the general population.
• Smoking: Smokers have a three times higher risk of renal pelvic cancer compared to non-smokers.
• Excessive coffee consumption: People who drink too much coffee have a 1.8 times higher risk of renal pelvic cancer.
• Painkiller abuse: Mainly refers to painkillers containing phenacetin, such as compound aminopyrine phenacetin tablets. Long-term use of phenacetin can cause kidney damage, kidney failure, renal pelvic cancer, and bladder cancer.
• Arsenic poisoning: Mainly occurs in Taiwan.
• Long-term exposure to toxic substances: Workers in chemical, petroleum, and plastic industries who are chronically exposed to toxic substances such as coal, asphalt, aniline, and dyes are more likely to develop renal pelvic cancer.
• Chronic urinary tract inflammation: Repeated urinary tract stones or chronic urinary tract inflammation can irritate the urothelium over time, potentially leading to cancer and causing squamous cell carcinoma of the renal pelvis.
• Certain genetic disorders: For example, patients with Lynch syndrome have a higher likelihood of developing renal pelvic cancer than the general population.
• Chinese herb nephropathy: Kidney disease caused by the use of Chinese herbs is often associated with the occurrence of urothelial carcinoma of the renal pelvis.

Having the above conditions does not necessarily mean one will develop renal pelvic cancer, but the probability is higher than in the general population.

Is renal pelvic cancer hereditary?

Most cases of renal pelvic cancer are not hereditary. However, if it is associated with Lynch syndrome, it may be hereditary.

Lynch syndrome is an autosomal dominant genetic disorder, and patients with this condition are prone to developing renal pelvic cancer.

DIAGNOSIS

What tests might be needed for renal pelvic cancer?

• Intravenous pyelography (IVP): Renal pelvic cancer appears as a filling defect in the renal pelvis on IVP. Currently, CT urography or gadolinium-enhanced MR urography can also be used as alternatives to IVP.

• Abdominal + pelvic CT or MRI: Renal pelvic cancer appears as a mass within the renal pelvis on CT or MRI. Additionally, these imaging tests can determine whether the cancer has spread or metastasized.

• Ureteroscopy or flexible ureteroscopy: These procedures allow direct visualization of the renal pelvis and enable biopsy collection for microscopic examination to detect cancer cells.

• Urine tests: During ureteroscopy, retrograde urine collection can be performed to detect cancer cells, providing more accurate results. Additionally, urine biomarkers can be tested to diagnose urothelial carcinoma.

• Cystoscopy: Cancer cells from renal pelvic cancer can travel with urine to the bladder and implant there, so cystoscopy is necessary to rule out bladder cancer.

Which diseases have symptoms similar to renal pelvic cancer?

Urinary tract infections, urinary stones, chronic nephritis, renal cell carcinoma, renal vascular thrombosis, and xanthogranulomatous pyelonephritis may present with symptoms similar to renal pelvic cancer, such as hematuria and flank pain.

Tests such as urinalysis, urine protein quantification, renal function tests, urine culture, urinary tract ultrasound, renal vascular ultrasound, and kidney CT or MRI can help differentiate these conditions.

TREATMENT

Which department should I visit for renal pelvic cancer?

Urology.

How is renal pelvic cancer treated?

• For localized renal pelvic cancer, surgery is the only potentially curative treatment.

  • The classic surgical method involves laparoscopic or open surgery to remove the affected kidney and ureter (since the ureter is a common site of recurrence, both the kidney and ureter must be removed).
  • After careful screening by doctors, some patients with low-risk cancer (e.g., tumor diameter <1 cm, solitary, low-grade tumor, no signs of tumor infiltration on CT, and good follow-up compliance) or severely impaired kidney function may undergo kidney-sparing surgery via open or endoscopic procedures.
  • Renal pelvic cancer is prone to concurrent bladder cancer, so postoperative intravesical chemotherapy is required.

• For advanced renal pelvic cancer with extensive lesions or metastasis, surgery is no longer an option. Chemotherapy may be administered, but the efficacy is uncertain.

• Radiotherapy is ineffective for renal pelvic cancer.

What are the risks of surgical treatment for renal pelvic cancer?

• Bleeding, infection, anesthesia complications, incisional hernia.
• Damage to surrounding tissues, such as pleura or diaphragm leading to pneumothorax, or injury to nearby intestines, liver, spleen, or pancreas.
• Renal insufficiency may occur after nephrectomy.
• Tumor seeding at the surgical incision.
• Improper handling of the ureteral stump may cause urine leakage and tumor dissemination.

What should be noted during hospitalization for renal pelvic cancer?

During hospitalization, ureteroscopy may be required. This is a minor procedure, not for treatment but for diagnosis. A definitive diagnosis is necessary before radical nephroureterectomy. Thus, two procedures are performed during hospitalization: the first for diagnosis and the second for treatment.

Surgery for renal pelvic cancer is routine and not particularly complex. With smooth recovery, patients can usually be discharged within a week postoperatively. Maintaining an optimistic attitude and cooperating with medical staff greatly aids recovery.

Is follow-up necessary after renal pelvic cancer surgery? How often?

Yes, to monitor for recurrence, metastasis, or bladder cancer.

Postoperative follow-up includes cystoscopy and urine cytology every 6 months. Some patients may also require upper urinary tract CT/MRI or ureteroscopy. After several years, follow-up intervals can extend to annually. Total follow-up duration should exceed 5 years.

Can renal pelvic cancer be completely cured? Will it recur?

Some early-stage patients with localized lesions can be cured, while others may succumb to the disease. Even after initial curative surgery, recurrence is possible, especially in patients who undergo kidney-sparing endoscopic surgery. Regular follow-up is essential.

What is the likelihood of death from renal pelvic cancer?

The average 5-year survival rate for renal pelvic cancer is about 70%, meaning 30% of patients may die within 5 years.

Mortality risk depends on tumor stage, grade, and lymph node involvement: higher stages/grades and lymph node involvement correlate with poorer prognosis.

DIET & LIFESTYLE

What should patients with renal pelvic cancer pay attention to in daily life?

Smoking is a risk factor for renal pelvic cancer and must be quit.

Most patients with renal pelvic cancer undergo nephroureterectomy, leaving only one kidney, which needs to be protected. Always inform your doctor of your medical history during visits so they can prescribe medications with minimal kidney damage. Actively prevent diseases like hypertension, diabetes, and gout that may impair kidney function. If these conditions already exist, manage them promptly.

What should patients with renal pelvic cancer pay attention to in their diet?

While strengthening nutrition, avoid overburdening the kidneys. Opt for high-quality protein sources like chicken, duck, fish, and eggs, and reduce red meat such as pork, beef, and lamb. Maintain a light diet, limit salt intake, and avoid processed and pickled foods.

Does renal pelvic cancer affect fertility?

Early-stage renal pelvic cancer has no direct impact on fertility. However, advanced or metastatic renal pelvic cancer, kidney dysfunction after nephrectomy, or treatments like chemotherapy and radiotherapy can affect fertility.

PREVENTION

Is there any way to prevent renal pelvic cancer?

Taking the following precautions can help reduce the risk of developing renal pelvic cancer:

• Quit smoking.

• Avoid excessive coffee consumption; limit intake to 1-2 cups per day.

• Do not abuse painkillers; consult a doctor before taking medication for chronic pain.

• Avoid prolonged exposure to toxic chemicals and ensure proper occupational protection.

• Promptly treat urinary tract stones or infections. Insufficient water intake, holding urine, and a sedentary lifestyle can contribute to urinary tract stones and infections—modify these unhealthy habits.