Kidney cancer is the ninth deadliest malignant disease among Singaporean males. The good news is, it offers a generally favourable diagnosis with better life expectancy than other more aggressive cancers. Find out more in our interview with Dr Ravindran Kanesvaran, senior consultant oncologist at the National Cancer Centre.
Q: What is kidney cancer or RCC?
Kidney cancer, also called renal cancer, starts from the kidneys, the fist-sized, bean-shaped organs either side of your spine. The most common form of kidney cancer is renal cell carcinoma (RCC), a solid tumour cancer, which accounts for 90% of cases in adults and is the ninth most common cancer in Singaporean men. Young children are more likely to develop Wilm’s tumour
Q: Who is most at risk?
Roughly two-thirds of RCC occur in men. Other than being male, there are two kinds of risk factors: modifiable and non-modifiable. Modifiable risk factors are ones that can be addressed with lifestyle changes such as obesity, smoking and high blood pressure which can be modified by losing weight, quitting smoking and managing your blood pressure.
We can’t do anything about non-modifiable risk factors. These include ageing, a family history of the disease and having advanced renal disease such as being on dialysis.
Q: Why is RCC twice as common in men than women?
Kidney cancer is associated with other chronic diseases involving high blood pressure and chronic kidney disease, as well as risk factors like smoking and obesity. The higher prevalence of such conditions in men could explain why kidney cancer is more frequently observed among males.
Q: How is it diagnosed?
Kidney cancer is diagnosed through blood and urine tests, imaging tests and biopsies of anything suspicious. However, due to the increased use of diagnostic imaging such as CT and ultrasound scans, many earlier stage kidney cancers are now being picked up during examinations for other diseases or routine medical check-ups.
Q: What are the treatment options?
For early stage kidney cancer when the tumour has not metastasised (spread to other parts of the body), surgery is conducted to remove the tumour from the kidney.
Before 2005 there was no standard of care for advanced RCC; it responded poorly to traditional chemotherapy with a poor prognosis of just 1 to 1.5 years. However, significant advancements have been developed in the last decade. We now have novel treatments such as targeted therapy and immunotherapy which can be used individually (or in combination), improving the prognosis dramatically.
Targeted therapy consists of drugs such as tyrosine kinase inhibitors (TKI) that target and inhibit particular pathways that promote cancer growth. For instance, they might switch off the signals to grow new blood vessels to feed the tumour and thus prevent or slow its growth. Side effects may include high blood pressure, heart problems and diarrhoea. It may also affect the thyroid gland and cause rashes on palms and soles of the feet.
Immunotherapy is a form of treatment that involves the stimulation of the patient’s immune system to recognise the cancer cells and kill them. Side effects include flu-like symptoms which can be well managed with medication.
Though rare, some patients may develop hyper-stimulation of the immune system, resulting in organ inflammation. About 90% or more of patients tolerate immunotherapy well with minimal side effects. For this reason, immunotherapy is a reasonable option in older kidney cancer patients.
Unfortunately, cancers can evolve and adapt to drugs over time and start growing or progressing again. But now that we have more immunotherapy and targeted therapy options when the first drug or first-line treatment begins to fail, we can try another or second-line treatment and so on. Currently, the recommended first-line treatment for RCC is usually an immunotherapy drug in combination with a targeted drug such as pembrolizumab and axitinib. If that fails, we move on the TKI cabozantinib alone as a second-line treatment, and then something else as a third-line and so on.
The current prognosis of advanced kidney cancer with targeted therapy and immunotherapy is between 3 to 3.5 years. There is ongoing research into new drugs and different combinations of existing immunotherapy and targeted drugs so that might improve in the future.
Q: Can RCC be cured?
We don’t like to say “cured” when talking about cancer as there is always a chance of it recurring, even if it’s not for many years. The prognosis is quite good for operable early stage 1 and 2 RCC, when the tumours are small and have not metastasised. However, even after a successful operation, the patient would have to be monitored and have regular check-ups in case it recurs. For advanced, inoperable RCC, the prognosis is 3 to 3.5 years with immunotherapy and targeted drugs.
Q: What are the survival rates compared to other common cancers?
Kidney cancer ranks 9th on the list of common cancer deaths in males and about 14th for women in Singapore between 2013 and 2017.
Although around 30% of RCC is detected at a late stage, advanced kidney cancer is not as aggressive as some other late stage cancers such as pancreatic and liver cancer. With the right treatment, RCC patients can have a good quality of life and a comparatively good prolongation of life too.
Q: What can people do to reduce their risk of developing RCC?
To reduce the risk of developing kidney cancer, one should maintain a healthy lifestyle and weight, and ensure that blood pressure is within the healthy range.
Q: What symptoms should people look out for and when should they consult a doctor?
Common symptoms of kidney cancer include blood in the urine, weight loss, loss of appetite, and/or a bulge or pain in the flank. Generally, symptoms do not usually show up until the cancer has metastasised. About 25% to 30% of kidney cancers are in the advanced stage by the time they are detected.
If you have any of the above symptoms, please seek medical treatment immediately. If you have a family history of kidney cancer and are over 50, you might want to ask your general practitioner about annual or biennial screening such as blood and urine tests or ultrasound scans. As with all cancers, the earlier the diagnosis the better the prognosis.
Dr Ravindran Kanesvaran is a senior consultant and deputy head of the Department of Medical Oncology at the National Cancer Centre in Singapore.