The treatment and causes of cancers originating from the kidneys’ urine-producing and draining sections, from the outer part of the kidney differ. The cancers mentioned here are those originating from the outer part of the kidney, the cortex. In urological terminology, these tumors are referred to as “RCC,” an abbreviation of Renal Cell Carcinoma.
Worldwide, 300,000 new cases of kidney cancer are diagnosed each year; this disease is more common in developed, industrialized countries. Throughout a lifetime, the probability of a man developing a kidney tumor is 1 in 69, while for a woman it is 1 in 116; that is, it is much more frequent in men.
It is more common in developed countries, with the most frequent occurrences in the Czech Republic and Lithuania.
Previously, kidney cancer was known as an elderly person’s disease and typically appeared in individuals over 65 years old. Today, with the frequent use of radiological diagnostic methods and the development of the check-up concept in advanced societies, it has begun to appear in younger ages.
The most common causes of kidney cancer include:
• Smoking
• Excess weight (obesity)
• Hypertension
• Familial: if it has occurred in first-degree relatives, the likelihood of developing kidney cancer increases 2.5 times
• Dialysis patients with kidney failure
• Acquired, non-congenital kidney cysts,
Symptoms of Kidney Cancer
The classic symptoms of kidney cancer are:
• A mass in the abdomen
• Blood in the urine
• Weight loss
• Abdominal pain
These four symptoms are now rarely encountered, appearing in only 7% of patients.
• Typically, they are discovered incidentally in patients undergoing ultrasound or CT for other reasons.
• In kidney cancers, certain symptoms and blood test values, known as “Staufer Syndrome,” may be elevated.
These symptoms include:
• Sudden onset of hypertension.
• Elevated sedimentation rate and/or CRP in the blood.
• Disruption of liver function tests.
• Elevated calcium levels in the blood
• Elevated Hb and Hct levels in basic blood tests (hemogram), indicating increased blood levels.
• After surgery, that is, after the removal of the cancerous mass or kidney, these blood levels should normalize. If they do not, it indicates the presence of metastatic kidney cancer foci in the body.
Kidney tumors are extremely aggressive and require prompt surgical intervention. Unfortunately, currently, 30% (one-third) of patients diagnosed with kidney cancer present with metastatic (spread to distant organs) disease at the time of diagnosis.
How is Kidney Cancer Diagnosed?
• Detection of a mass in the kidney through abdominal ultrasound or CT performed for other reasons can lead to a diagnosis.
• For a definitive diagnosis of kidney cancer, a contrast-enhanced abdominal CT is necessary.
• As kidney cancers tend to progress into the main renal vein and the main body vein (IVC), a contrast-enhanced upper abdominal MRI is required in many cases to evaluate these veins.
What to Do if a Cyst or Cystic Formation is Detected in the Kidney on Ultrasound?
This is a situation we frequently encounter.
• For incidentally found kidney cysts, a contrast-enhanced (IV contrast) upper abdominal MRI is performed. The MRI evaluates the structure of the cyst in the kidney, determining whether it is a risky cyst or possibly cystic cancer.
• You can compare the MRI findings with your own patient’s results based on the criteria below. The experience of the radiology doctor interpreting the MRI is crucial. In urology, this interpretation is known as the Bosniak classification.
Bosniak Category I: This is a benign cyst, not cancer!
Bosniak Category II: This is also a benign simple cyst, not cancer!
Bosniak Category IIf: A very small portion of these may contain cancer; close follow-up is required!
Bosniak Category III: More than half of these are cancerous; surgery is recommended!
Bosniak Category IV: Almost all of these cysts are cancerous; surgery is the definitive solution!
Should a Kidney Biopsy be Performed if a Mass is Found in the Kidney?
This is a question we frequently encounter.
According to the EAU (European Association of Urology) 2022 guidelines on kidney cancer diagnosis and treatment:
• When a mass is detected in the kidney, a contrast-enhanced CT or MRI can almost certainly determine whether the mass is cancerous. Therefore, biopsy is typically avoided to save time and reduce the risks associated with the procedure.
• Mass metastasis (spread) from other organs to the kidney is seen in about 12% of cases; in such cases, a kidney biopsy is necessary.
• In patients who do not wish to undergo surgery and present with a small kidney mass, a biopsy may be performed if they choose to undergo monitoring instead.
• If a tumor is found in the kidney but ablation treatments such as radiofrequency ablation or cryoablation are planned instead of surgery, a biopsy of the kidney mass is required.
• In advanced kidney cancers, we want to determine if there are changes in the cancer cell type, such as “sarcomatoid” or “rhabdoid,” which would influence the decision to operate. If these cell types are present, surgery may not be performed. In advanced cancers where the patient’s overall condition is poor, a biopsy of the mass is necessary.
• For cystic kidney masses, because the proportion of cancer cells in the cystic fluid is very high, biopsy is generally not recommended.
Staging:
As with all cancers, knowing the stage of kidney cancer is crucial for understanding the disease progression and planning treatment.
• Stage 1 (T1): Tumors confined to the kidney, not extending beyond the kidney, not involving lymph nodes, and up to 7 cm in size.
• Stage 2 (T2): Tumors confined to the kidney, not involving lymph nodes, and greater than 7 cm in size.
• Stage 3 (T3): Tumors extending into the renal vein, the urine collection system, or the surrounding fat tissue, or extending into the body’s largest vein (VCI: Inferior Vena Cava) but not involving lymph nodes.
• Stage 4 (T4): Tumors that have spread to lymph nodes around the kidney, or to the adrenal gland, or beyond the outer layer surrounding the kidney.
In addition to staging, the aggressiveness of the cancer is determined by the Grade (the degree of change in cancer cells):
Post-surgery examination of the tumor will reveal a Grade of 1, 2, 3, or 4, with higher numbers indicating greater aggressiveness.
Treatment of Kidney Cancer
The treatment for kidney cancer, once diagnosed, is to undergo surgery as soon as possible. In other words, the treatment is “surgical intervention.” Surgical procedures performed by experienced hands yield very positive results. If the tumor has not spread to distant organs, surgery alone is usually sufficient. The surgical treatment for kidney cancer involves removing the cancerous kidney along with surrounding tissues (to prevent the tumor from spilling out during the operation).
This surgery is called “RADICAL NEPHRECTOMY.” It is a major operation performed under General Anesthesia. It can be carried out through open surgery, robotic surgery, or laparoscopic surgery.
Is it possible to preserve the kidney and only remove the tumor?
With the increasing use of radiological imaging, advancements in medical technology, and the establishment of the check-up concept, we are now able to detect kidney tumors at very small sizes. In such cases, we apply a surgical technique called “Nephron-Sparing Surgery” or “Partial Nephrectomy,” which involves removing only the tumor while preserving the rest of the kidney.
2022 Treatment Protocols for Kidney Cancer According to EAU (European Association of Urology) and AUA (American Urological Association)
• For Stage T1 cancers with tumors up to 5 cm, if the tumor is in an appropriate location, “Robotic Partial Nephrectomy” is recommended. This procedure removes only the cancerous portion of the kidney, thereby preserving kidney function.
• EAU and AUA guidelines recommend that for tumors up to 5 cm, “Robotic Partial Nephrectomy” should be the first choice if the tumor’s location is suitable.
• Partial Nephrectomy can also be performed via open surgery or laparoscopic surgery, in addition to robotic surgery.
• We perform the majority of our partial nephrectomy surgeries using robotic techniques. After the necessary preparations, patients are admitted to the hospital on the day of surgery, and the surgery is conducted on the same day. Patients typically stay in the hospital for 3-4 days.
• For larger tumors, “Radical Nephrectomy” is the ideal treatment. This involves removing the kidney along with the tumor and surrounding tissues.
• During Radical Nephrectomy, extensive lymph node dissection, as performed in bladder cancer, has been found to offer minimal benefit to disease progression. Therefore, only lymph nodes larger than 2 cm in the affected area are removed.
• If preoperative MRI or CT scans show no tumor progression to the adrenal gland (adrenal gland = suprarenal gland), the adrenal gland is not removed with the kidney during surgery.
For patients with impaired kidney function, a single kidney, or tumors detected in both kidneys simultaneously, “Partial Nephrectomy” is performed to help preserve kidney function to some extent.
Surgical Treatment for Stage T3 (Locally Advanced) Cancer:
• In advanced cases, surgical treatment is significantly more challenging than conventional surgery. The surgical team must be highly experienced to handle such cases.
• What to do when the tumor thrombus has extended from the renal vein into the main body vein?
• For these patients, we first assess whether there is distant metastasis (to the lungs, liver, bones, brain, or spinal cord). If there is no distant spread, we proceed with this highly challenging surgery, which requires substantial experience.
Absolute Recommendations from EAU and AUA:
• If the thrombus is not adherent to the wall of the main vein, patients benefit greatly from the surgery. Removing the thrombus will unblock the obstructed main vein, restoring normal blood flow.
Frequently Encountered Situations:
• In cases of advanced kidney cancer where the tumor has invaded the main vein or not, if there is no distant organ metastasis, patients often use systemic oral medications provided by oncologists instead of undergoing surgery. The effectiveness of these medications in shrinking the tumor or improving the patient’s condition has not yet been proven. Currently, this treatment is considered experimental worldwide.
• For Stage T3 advanced cases, lymphadenectomy (removal of lymphatic tissue) during surgery should only be performed on visible and palpable enlarged lymph nodes. Extensive lymph dissection is unnecessary.
Before making a surgical decision for advanced kidney cancer, we perform several tests. If the results are not satisfactory, we may conclude that surgery would not be very beneficial for the patient and may decide against it.
These tests include:
1. General performance score of the patient (Karnofsky score)
2. Presence or absence of severe weight loss
3. Duration since diagnosis: Is it longer than 11 months?
4. Hemogram analysis: Lymphocyte count, platelet count**
5.Is hemoglobin (Hb) level lower than normal, and are neutrophil and platelet counts elevated?**
6. If a biopsy has been performed, are there any rhabdoid or sarcomatoid cells present?**
For patients with very advanced, inoperable kidney cancer who have local issues such as bleeding, the appropriate intervention is “embolization,” which involves blocking the arteries causing the bleeding through angiography.
KİDNEY INTERNAL CANCERS (RENAL PELVİS AND URETER CANCERS)
Kidney internal cancers (renal pelvis and ureter cancers), also referred to as upper urinary system cancers.
– Renal pelvis cancer originates from the pool where urine collects after forming in the kidney, also known as the kidney pelvis.
– The ureter is the tube that carries urine from the kidney to the bladder, also known as the urinary tract.
– Urine is formed in the kidney, first moves to the renal pelvis (the pool in the kidney), then passes to the ureter, and from the ureter flows into the bladder.
– Renal pelvis cancer arises from the walls of this pool, i.e., cancers originating from the internal part of the kidney.
– Treatment differs from cancers originating from the external part of the kidney.
– Since the external urinary tract (urethra in both males and females) and the area where urine exits the kidney are composed of the same tissue, the likelihood of having cancer in both the kidney pelvis or ureter and the bladder simultaneously is 17%.
– Tumors in the ureter occur 70% in the lower part near the bladder, 25% in the middle of the ureter, and 5% in the upper part near the kidney.
Causes
– It is seen twice as often in men compared to women.
– Common in Balkan countries.
– Tobacco use increases the risk of developing this disease by 5 times.
– Long-term kidney stones increase the risk of developing this disease.
– Genetic conditions such as Lynch syndrome (non-polyposis colorectal cancers).
– 11% of patients have a history of chronic pain medication use.
– Drinking water from artesian wells (due to inorganic arsenic content).
Symptoms
– Hematuria (blood in urine) is the most common and significant symptom.
– It is not necessary to be visible; sometimes it appears continuously in urine tests.
– Pain in the left or right flank due to blockage of urine flow by blood clots or tumors.
– Burning sensation during urination.
– Swelling in the kidney due to blockage visible on kidney and bladder ultrasound.
– Urine sample cytology is used to check for malignant cells (cancer cells) in the urine.
– IV contrast-enhanced CT urography shows the inside of the kidney, ureter, and bladder, guiding suspicion but may not diagnose very small tumors.
– The most important method for diagnosis is “Flexible Ureterorenoscopy”: using a camera system to enter the bladder through the external urinary tract, then using a flexible ureterorenoscope to reach from the bladder through the ureter to the kidney to see where the tumor is, whether in the ureter or kidney, obtaining a sample for pathology (biopsy) for diagnosis.
– Diagnosing with flexible ureterorenoscopy requires significant experience and high-level equipment, so diagnoses are often made late.
– In 17% of patients with renal pelvis or ureter tumors, cancer may also be present in the bladder simultaneously. Therefore, examining the bladder with a camera is essential; cystoscopy is performed before starting flexible ureterorenoscopy to check for any abnormalities in the bladder.
– After diagnosis, staging is performed to determine if the disease has spread, using IV contrast-enhanced thoracic CT.
– PET CT can also provide the same result as thoracic and abdominal CT.
Treatment
– The most important factor determining treatment is whether the cancer is high grade (aggressive) or low grade (less aggressive) based on biopsy results.
– Whether the patient has two kidneys (one may have been removed previously or may be congenitally absent).
– The function of the remaining kidney is a critical criterion.
– If high-grade cancer is found in the biopsy and the function of the other healthy kidney is good, the treatment for cancers in the kidney, upper ureter, or lower ureter is usually “Nephroureterectomy + Partial Cystectomy,” i.e., the removal of the kidney, ureter, and one-third of the bladder.
– Removing only the kidney and ureter without removing the bladder portion can lead to a 45% chance of disease recurrence, which is considered incomplete surgery.
– If the tumor is only in the lower part of the ureter or within the bladder, removing only the lower ureter and one-third of the bladder without removing the kidney may be sufficient. However, this decision requires ensuring with flexible ureterorenoscopy that there are no tumors in the upper ureter and kidney.
Nephroureterectomy + Partial Cystectomy Surgery Method
It can be performed openly, robotically, or laparoscopically. According to the latest EAU (European Urology Association) 2022 update, for high-grade cancers, the first option should be open surgery, meaning Nephroureterectomy + Partial Cystectomy should be performed openly.
Low-Grade (Less Aggressive) Cancers:
– If the biopsy result shows low-grade cancer and the tumor in the kidney is large or numerous, the treatment will still involve removing the kidney, ureter, and one-third of the bladder.
– If the biopsy result is low-grade but the tumor in the kidney is not very large, flexible ureterorenoscopy and laser treatment may be performed.
– For tumors found in the middle of the ureter that are low grade, only the tumorous part is removed, and the two ends of the ureter are reconnected. Treatment without removing the kidney is possible.
Chemotherapy Treatment
– After diagnosing and staging the disease, if metastasis to distant organs is detected, chemotherapy is required.
– If there is spread to surrounding lymph nodes but no distant organ metastasis, the decision between preoperative chemotherapy or postoperative chemotherapy depends on:
– Since chemotherapy drugs are excreted by the kidneys, performing surgery first is risky because the patient will have one kidney left. Therefore, preoperative chemotherapy is preferred if there is lymph node spread around the kidney.
– Preoperative chemotherapy is called “neoadjuvant chemotherapy.”
This article is updated according to the 2022 guidelines from the EAU (European Urology Association) and AUA (American Urological Association).