Kidney cancer cases increasing
This is Part 2 of Agelessonline’s story on Molly Lim and her kidney cancer. Find out more about kidney cancer.
BY: Yen Fang
Kidney cancer is a relatively uncommon cancer and historically accounts for only about three percent of all cancer incidences. However, worldwide incidence is increasing by about two percent to three percent per year and in the US, 39,000 new cases were diagnosed in 2006 alone. In Singapore, the incidence is 5.4 per 100,000 per year, according to the Singapore Cancer Registry. The rates locally have also approximately doubled over the last 35 years, according to Molly Lim’s doctor, Dr Tiong Ho Yee (seen left with Lim), consultant, Department of Urology, National University Hospital.
In addition, the mortality rate from metastatic (spread to other parts of the body) kidney cancer per unit population seems to be rising with 13,000 reported deaths in 2006 in the US. It is now considered to be the most lethal urologic cancer in the US. In Singapore, the age-adjusted cancer specific mortality is 2.4 per 100,000 per year for men and 1.3 per 100,000 per year.
Agelessonline talks to Dr Tiong about the symptoms and treatments, as well as re-occurrence:
What are the symptoms, causes and factors?
In early cases, patients often do not complain of any symptoms. With increased screening being performed such as X-rays, ultrasound and CT scans, most small renal cancers are being picked up incidentally at very early stages and these patients will not have any symptoms. In the late stages, patients are classically described as presenting with loin pain, loin swelling (lump) and blood in the urine (haematuria), fatigue, weight loss, and pain or a mass on the side or lower back. This presentation is less common today.
With regards to causes, a small number of kidney cancers may be hereditary, especially in families with a history of kidney cancers; otherwise most cancers are termed as sporadic. This means that there is no known cause; however, the incidence of kidney cancer is higher in smokers and in patients with kidney failure on long-term dialysis. Age is not a cause but an association and kidney cancers, like most other cancers, more commonly occur in the elderly than the young.
Can it be prevented?
At the moment, there are no current established, preventative measures for kidney cancer. However, healthy living is important and as smoking is a known association, not smoking is probably the best preventative measure one can take.
What kinds of treatments are available for those with cancer of the kidney?
The treatment for kidney cancer depends on the stage of the kidney cancer and also needs to be individualised for each patient depending on their health condition. For small cancers less than 4cm, these are amenable to partial nephrectomy – where only part of the kidney with the kidney cancer is excised/removed. The remaining kidney is then repaired with the result of preserving as much residual kidney function as possible. For partial nephrectomy, the surgery may be open wound or minimally invasive using key-hole laparoscopic or robotic surgery, depending on the location of the cancer on the kidney.
For larger kidney cancers, the entire kidney needs to be removed (radical or total nephrectomy) to achieve the best cancer control. This can again be done either via an open wound or using key-hole laparoscopic surgery. The advantage of key-hole or robotic surgery over open surgery is a quicker recovery and less pain, but it needs to depend on the suitability of the case.
In patients whereby the cancer has been shown to have spread to other organs, there may still be a role for surgery but will need to be used in combination with chemotherapy agents.
What is the likelihood of kidney cancer re-occurring?
The likelihood of kidney cancer recurring or progressing after nephrectomy for initial presumed localised cancer depends on the stage of the kidney cancer. If the initial stage is Stage 1 (meaning that the tumours are less than 8cm in size), then 90 percent will remain disease-free at five years. If the initial stage is Stage 2 (more than 8cm) or Stage 3 (involving major veins), 25 percent of patients would have disease progression by five years. If the tumor is Stage 4, then less than 25 percent would be disease-free at five years. This is according to data from the Memorial Sloan Kettering Hospital in 2008.
Metastatic kidney cancers traditionally present a bleak outlook with less than 50 percent of patients surviving more than a year after diagnosis. One reason is that renal cell carcinoma (the most common type of kidney cancer in adults) is resistant to chemotherapeutic agents that have yielded response rates of less than five percent. However, over the last two to three years, targeted molecular agents such as Sorefenib (Bayer and Onyx Pharmaceuticals), Sunitinib (Pfizer) and others have arrived on the market as effective treatments of advanced kidney cancers.
These micromolecular drugs are enzyme inhibitors and they selectively inhibit proteins whose functions include stimulation of blood vessel growth, which kidney cancers are dependent on for growth. When compared to placebo, progression free survival was significantly greater for metastatic kidney cancer patients treated with these agents. As these new agents are orally taken, patients are not admitted to the hospital for administration. Now, more than ever, the outlook for metastatic kidney cancer is looking brighter despite higher mortality in the past years.
Are there side effects to these new medications?
Side effects include gastrointestinal symptoms such as nausea, anaemia, low white cell count as well as inflammation of hands and feet as well as mucous membranes. Therefore, careful monitoring and follow-up is needed for side effects’ assessment and managment.
In what way are they better than the traditional treatment of chemotherapy?
The response of kidney cancers to these new agents are significantly better than traditional chemotherapy with resultant better survival.
With a removal of one kidney, can a person still enjoy a full life? What do they need to keep in mind with one kidney? Do they have to take medication the rest of their lives? What about chemo or even dialysis?
In patients with the removal of the entire kidney for cancer, he or she can still enjoy a full life after recovering from the initial post operative phase. It is important to protect the other kidney from deteriorating in function as this is the only remaining kidney. It has been shown that patients with solitary kidney have greater worsening renal function in the presence of other medical conditions such as hypertension, diabetes mellitus and hyperlipidemia. Hence, careful control of one’s blood pressure is important with regular checks, appropriate blood pressure medications and controlled dietary salt intake.
For patients with diabetes, sugar control needs to be optimised and high cholesterol and lipid levels can be managed with dietary controls and exercise, and medication if necessary. In patients who are healthy otherwise with no other medical conditions (such as healthy patients who have donated their kidneys for transplantation), medication may not be needed at all. If kidney function is well preserved, dialysis will not be needed.
There have been kidney transplants in the past. If one can live well on one kidney, why is a transplant then necessary?
Kidney transplants are not indicated if a patient has a functioning kidney. It may be necessary if the remaining kidney, after removal of the opposite one, fails completely. In these cases, transplants are only possible if the patient is cancer-free for more than five years.
Can someone survive on even half a kidney?
Patients with cancer in a solitary kidney (after they have lost the other kidney beforehand through surgery or disease) will need an obligatory partial nephrectomy to be performed and may result in this situation of half a kidney. In general with half a kidney, a patient will not have a completely normal kidney function but may have adequate function for survival without the need for dialysis.
TO SEE PART 1 of this story – go here.
** WRITER’S NOTE: The cancer medications are extremely costly. It is vital that people get insurance as without it, people would have to pay out-of-pocket.