The Silent Kidney Cancer Disease

Kidney cancer usually does not have signs in its early stages. However, in time, signs such as blood in the urine may develop. By that time, the cancer may have advanced.

In this article, we speak to our urologist Dr. Chong Kian Tai, from Surgi-TEN Specialists at Farrer Park Hospital, to learn about more about the silent disease. Dr. Chong manages both general urology and complex urologic cancers.

Prevalence of Kidney Cancer in Singapore

Kidney cancer is one of the top 10 cancers in men in Singapore. The disease usually occurs when there is a cancer growth in a particular area of the kidney called the renal parenchyma. According to the Singapore Cancer Registry’s 50th Anniversary Monograph that covers data from 1968 to 2017, kidney cancer is the eighth most common cancer among Singapore men at the moment.

“In the same report, we also find that the incidence of kidney cancer has increased exponentially and in fact, is one of the top two most frequent cancers that grows the fastest in the incidence over the last 50 years,” Dr. Chong explained.

“Majority of patients actually do not have symptoms when they have kidney tumour. Some patients also have back pain and when they do an ultrasound or CT scan, they actually found a kidney tumour that they did not expect.”

Gender Disparities

“While it ranks high for men, kidney cancer is not in the top 10 cancers among women,” Dr Chong said.

Men are more frequently diagnosed with kidney cancer than women, sometimes with a more aggressive histology, larger tumors, a higher grade and stage, and worse oncological outcomes. Lifestyle habits and sex steroid hormones could have a possible role in explaining these gender disparities. However, gender-related differences in kidney cancer are still being reviewed.1

Risks and Preventions

“In kidney cancer, there are two different kinds of cancers. Some are genetic-related where a family member may have a gene predisposed to kidney tumors. This usually happens in a younger age,” Dr Chong said.

“There are also cancers of the kidney that happen in the older age group and not really related to the genes, so it depends on the age group they have and whether there are any family members with kidney cancer,” he added.

When asked if kidney cancer is diet related, Dr. Chong said: “The kidney cancer is not known to be linked to a diet itself, but we do know that if you stop smoking and have a healthy diet, and stay healthy for your heart, it will be healthy for your kidneys,” he replied.

With kidney cancer being a silent killer, Dr. Chong strongly encourage regular health checks to ensure proper kidney health. “When there's a back pain or blood in the urine, even if you don't actually see the blood in the urine itself, you can go to any general practitioner to do a dipstick of the urine to detect blood traces,” he said.

“What is a dangerous and worrying sign is that according to the Singapore Cancer Registry over the last 50 years, it was found that at least one quarter of patients with kidney cancer are already in stage four when diagnosed,” he cautioned.

“Once you're in stage four of kidney cancer, it is more complicated to manage in addition to having surgery to remove the tumor. I hope that more patients will understand that while early stage kidney cancer may not have symptoms, it is important to go for regular screening and consult a doctor early if they feel uncomfortable,” he added.

Treating Kidney Cancer

Managing kidney cancers requires a multidisciplinary team of doctors. The urologist is actually the surgeon who treat kidney problems requiring surgery and the nephrologist, who are also called renal physicians, help manage the diseases of the kidney. When it comes to managing cancer, medical and radiation oncologists also have their part to play.

“When a patient has a suspected kidney tumor, I always want to find out whether it's benign or malignant by conducting a CT scan of the kidney. It helps to differentiate whether the tumor is likely to be cancerous or not. What we have found is that in those patients with a small kidney tumor less than four centimetres, among them, about 20% of the tumours may not have cancer,” Dr. Chong explained.

“If it is a small kidney tumor, one of the treatments is to remove the kidney tumor while saving the rest of the normal kidney and remaining functions,” he said.

“However, if the kidney cancer is stage four, we work with a medical oncologist to give medication to help remove and kill off the cancer cells that may have also spread to other parts of the body outside of the kidney.”

Dr. Chong said that in the event if part of the kidney function is lost, our body adapts quickly and the remaining kidney sometimes will take over. “It is like having two people who is supposed to do some work. When one person is out of action, the other person actually work a bit more and take over the function.”

After removing all the cancers that are found in the kidney, patients have to be regularly reviewed and monitored with CT scans or imaging tests to make sure the cancer do not come back and doctors would generally aim to keep patient cancer-free for five years.

However, for many people, the stage 4 kidney cancer might never go away completely. Some people may get regular treatment with immunotherapy, targeted therapy or other treatments to try and help keep the cancer in check.

However if the patient's kidney function is not so good post -surgery, patients may be referred to the nephrologist for dialysis, or to make sure kidney function does not worsen.

Besides surgery to remove the tumor, there are other treatment modalities such as inserting a small needle into the kidney tumor to freeze or heat up the tumor to kill off the cancerous cells in the kidney.

In a study2 that Dr .Chong was involved in, findings showed sustained improvement in kidney function for partial removal of kidney. These patients are aging, Asian and have kidney cancer. “For patients who are older than 65 years old, the clinical priority now is to only remove the tumor and spare the remaining healthy kidney that do not have cancer.”

Living as a Kidney Cancer Survivor

Managing kidney cancers requires a multidisciplinary team of doctors. The urologist is actually the surgeon who treat kidney problems requiring surgery and the nephrologist, who are also called renal physicians, help manage the diseases of the kidney. When it comes to managing cancer, medical and radiation oncologists also have their part to play.

Completing treatment can be both stressful and exciting. On one hand, it is a relief to finish treatment, yet it is hard not to worry about cancer coming back.

“For patients diagnosed with stage one cancer, their survival of up to 10 years is more than 90% chances. However if it is stage four kidney cancer the prognosis is not so good. Most patients may survive for another three to five years with the multiple treatment,” he said.

“However, there are many ongoing research in managing stage four kidney cancer such as new immunotherapy medication and new targeted therapy treatment,” he added.

Nevertheless, survivorship will always serve as a strong motivator to make appropriate lifestyle changes. Patients who recovered are encouraged to follow and practice good health habits like eating well, managing stress and a healthy dose of physical activity to rebuild strength and energy level.


1 Mancini, M., Righetto, M., & Baggio, G. (2020). Gender-Related Approach to Kidney Cancer Management: Moving Forward. International journal of molecular sciences, 21(9), 3378.

2 Lam, J., Tan, S. Y., & Chong, K. T. (2020). Is partial nephrectomy worth performing compared to radical nephrectomy for small, localised renal cortical tumours in geriatric patients? Singapore medical journal, 61(4), 190–193.

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