Kidney Cancer - Renal Cell Carcinoma
Kidney Cancer :: Prostate Cancer
Bladder Cancer :: Testicular Cancer
The Kidneys are essential organs that form part of the genito-urinary system. The kidneys filter the blood and the waste products are transferred through the ureters to be stored in the bladder as urine. Urine is then discharged through the urethra to empty the bladder.
The kidneys also produce three important hormones: erythropoitin (EPO), which triggers the production of red blood cells in bones; renin, which regulates blood pressure; and vitamin D, which helps regulate the body's metabolism of calcium necessary for healthy bones.
Renal Cell Carcinoma (RCC)
There are several types of cancer that can affect the kidneys. Renal cell carcinoma (RCC), is the most common form and accounts for approximately 85% of all kidney cancers. In RCC, malignant cells develop in the lining of the kidney's tubules and typically grow into a mass called a tumour. Single tumors are the norm, although more than one tumour can develop within one or both kidneys. As with most cancers, the earlier kidney tumours are discovered, the better a patient's chances for survival. Tumours discovered at an early stage often respond well to treatment. Survival rates in such cases are high. Tumours that have grown large or metastasised (spread) through the bloodstream or lymphatic system to other parts of the body are much more difficult to treat and present a greatly increased risk for mortality.
In New Zealand, kidney cancers count for just over 3% of all malignancies diagnosed in men and women each year.
In order to accurately determine whether or not a patient has cancer, a physical examination
and a number of other tests may be required to rule out any other conditions.
Computed Tomography scans are highly detailed x-rays that show the internal organs of the body. Dyes may also be injected to help see the area more clearly.
Magnetic Resonance Imaging detects anatomy on the basis of the way different tissues behave in a magnetic field. Dyes may be used to improve detail with these scans as well.
Many patients with RCC have haematuria or blood in their urine. Often this blood is present in such small amounts or so diluted in the urine that it cannot be seen with the naked eye (called microscopic haematuria). To detect haematuria a chemical test of the urine usually is prescribed. On occasion, cells found in the urine are examined under a microscope for abnormalities. This procedure is called urine cytology.
Another procedure typically used in the diagnosis of RCC involves microscopic examination and/or chemical analysis of the patient's blood. These tests screen for indicators that may demonstrate the presence of cancer, such as:
- Anaemia (too few red blood cells; caused by internal bleeding, a common cancer symptom)
- Polycythaemia (too many red blood cells; sometimes caused by cancerous tumors in the kidney that trigger the release of EPO, a hormone that increases red blood cell production in bone marrow)
- Hypercalcaemia (high blood calcium levels)
- Elevated liver enzymes
(sometimes characteristic of RCC)
Because blood in the urine can result from other health problems, cystoscopy may be advised to determine precisely where the internal bleeding is occurring. In cystoscopy, a long, thin, flexible optical scope is inserted through the urethra and into the bladder. Visual examination of the urethra, bladder, and kidneys is undertaken to locate the site of bleeding. This is a 5 minute outpatient procedure that is performed under local anaesthetic and does not require an incision.
Fine Needle Biopsy
If a tumour has been diagnosed, a radiology (X-ray) specialist may take a biopsy of cells with image guidance to be examined in the laboratory.
Up to 90% of primary renal tumours are renal cell carcinomas which can be subtyped as
- Clear cell (conventional) RCC
- Papillary RCC
- Chromophobe RCC
Variants such as sarcommatoid change and collecting duct carcinoma are rare and have generally more aggressive behavior.
Non-kidney based cancers can present in the kidneys. Transitional cell carcinoma or TCC (a tumour of the cells lining the ureters and bladder) , lymphoma (a disease of the lymphatic system) and metastases (secondary spread from other organs) are the most common examples of these.
Benign (non-cancerous) kidney tumours also exist. The most common are Oncocytoma and Angiomyolipoma (AML). Treatment may be recommended for these lesions due to the risk of cancer or of complications such as bleeding.
Staging of Kidney Cancers
As discussed with other malignancies, the Tumour, Node and Metastases system stages RCC tumours.
1 – limited to the kidney and <7cm
2 – limited to the kidney and >7cm
3 – extending out of the kidney, into the adrenal or blood vessels
4 – extending out of the kidney and into adjacent organs
||reflects involvement of the regional lymph glands
||reflects involvement of other organs by disease spread
Kidney cancer grading is based on the Fuhrman system. Currently tumours are given a grade between 1 (least aggressive) and 4 (most aggressive).
There are a number of treatment options for kidney cancer; the ideal treatment depends on a number of factors, including the extent of the tumour and other existing medical problems. Treatment options vary and these should be discussed to tailor best individual course of treatment. They include Active Surveillance, Surgery, Radiofrequency ablation, Chemotherapy and Radiation Therapy.
This is conservative management in which treatment is postponed and the mass is followed with imaging at intervals to assess growth. It may be appropriate for small lesions, particularly for patients with other significant medical problems.
The most common form of surgery for RCC, radical nephrectomy involves removal of the entire kidney, often along with the attached adrenal gland, surrounding fatty tissues and nearby lymph nodes (regional lymphadenectomy), depending upon how far the cancer has spread.
It may be possible to remove only the cancerous tissue and part of the kidney if the tumor is small and confined to the very top or bottom of the kidney. A partial nephrectomy may be the procedure of choice for patients with RCC in both kidneys and for those who have only one functioning kidney.
Laparoscopic techniques allow the kidney to be removed using three or four 1cm “key hole” incisions in the abdomen. The most favoured approach worldwide is the trans-peritoneal approach (from the front), but a retroperitoneal approach (through the flank) may also be used. Conversion to the standard open operation is easily accomplished, should technical difficulty be encountered but is rarely required.
Advantages of Laparoscopic Nephrectomy
The main advantage of laparoscopy is the reduction of pain and post-operative recovery time. The patients usually can mobilise unassisted two days post-op and often are ready for discharge at that time. Patients receiving the open operation often cannot walk until day 4 or 5 and are not ready for discharge until a week after surgery.
Most patients after laparoscopic nephrectomy are able to return to normal activities by the third or fourth week, while patients after the open operation usually take 6 to 8 weeks.
Recent results from multi-centre trials have shown the laparoscopic operation to be as safe in the treatment of localised renal cancer as the traditional open operation, hence widening the indication for the operation.
What types of kidney disease are suitable for laparoscopic nephrectomy?
Most patients with benign kidney disease that requires nephrectomy are suitable, although infected or inflammatory kidneys are more difficult hence the open conversion rate is higher. Most kidney cancers are suitable for laparoscopic nephrectomy.
Patients with renal cysts that are symptomatic are ideally suited to laparoscopic de-roofing, which is technically less demanding than nephrectomy.
Disadvantages of Laparoscopic Nephrectomy
This operation is technically demanding and is associated with a steep learning curve. Initially operating times are longer than for the open operation, although with experience this reduces significantly.
Problems associated with CO2 distension of the abdomen can cause issues such as shoulder pain and CO2 retention. Rare problems including gas embolisation and tumour spillage have been reported.
Overall, reported complications from laparoscopic nephrectomy are comparable to that of open surgery and the advantages usually outweigh the disadvantages.
This procedure is undertaken with image guidance and involves heating the tumour by way of a device introduced through the skin. To date, cancer outcomes have not been as good as surgical removal however it is well tolerated and it may be a reasonable option particularly for patients unsuitable for surgery.
Traditionally chemotherapy has been very poorly effective in the treatment of kidney cancer that has spread however in the last few years great advances have been made in this area.
The tyrosine kinase inhibitors have been shown to have a significant impact on survival time and may be a reasonable option, sometimes in combination with nephrectomy, for kidney cancer that has spread beyond the kidney. This therapy is administered and monitored by a medical oncologist.
Radiation in the form of x-rays or other high-energy rays is used to shrink and kill cancer cells in some kidney cancer patients. The radiation is delivered as a focused beam (external beam radiotherapy) that is projected into the body through a linear accelerator.
Radiation therapy is used occasionally as an adjuvant (follow-up) therapy to kill any cancer cells. This is palliative therapy to lessen pain or bleeding in patients with inoperable or widespread metastatic RCC.
Follow-up Care and Recurrent Kidney Cancer
Some patients who undergo surgery to remove a cancerous kidney or kidney tumours experience a recurrence of the disease. For this reason, patients usually undergo a regimen of follow-up examinations after surgery. These examinations may include a chest x-ray, CT scanning and blood tests at regular intervals. If the disease recurs but remains confined to a few small areas, additional surgery may be recommended. Radiation or chemotherapy also may be given as an adjuvant or palliative (relief-giving) treatment.