What is Kidney Cancer?
Kidney cancer happens when an abnormal growth develops in kidney tissues and, over time, forms a tumour. A malignant (cancerous) tumour often develops in one kidney. However, in rare cases, the cancer can develop in both kidneys.
Most kidney cancer cases are discovered in their late stages in Singapore, as symptoms typically do not appear during the initial stages. Kidney cancer is the seventh most common cancer among men, with cases rising between 2-3% annually.
There are several types of kidney cancer, with renal cell carcinoma (RCC) being the most common. Here are the main types of kidney cancer:
Renal Cell Carcinoma (RCC)
RCC begins in the lining of the small tubes, known as tubules, in the kidneys, which help to filter waste from the blood. The subtypes of RCC include:
- Clear cell renal carcinoma: the most common type, and it appears as transparent or pale cells when viewed under a microscope.
- Papillary renal cell carcinoma: characterised by finger-like projections in the tumour cells.
- Chromophobe renal cell carcinoma: a less common form of kidney cancer with unique cell features. It tends to have a better prognosis compared to other types.
- Collecting duct renal cell carcinoma: a rare and aggressive type of kidney cancer that starts in the collecting ducts of the kidney.
- Unclassified renal cell carcinoma: when kidney tumours do not fit into the above categories, they are classified as unclassified RCC.
Transitional Cell Carcinoma (Renal Pelvis Cancer)
Transitional Cell Carcinoma refers to cancer that begins in the renal pelvis and ureter. Subtypes of transitional cell carcinoma include:
- Wilms tumour: a rare type of kidney cancer that mainly affects children, typically those under the age of 5, and often has a good prognosis.
- Renal sarcoma: a rare and aggressive cancer that develops in the kidney tissues.
Oncocytoma, commonly known as renal oncocytoma or oncocytoma of the kidney, consists of oncocytes with unusually large mitochondria. Oncocytoma is a benign or non-cancerous type of kidney tumour.
What causes Kidney Cancer?
Kidney cancer occurs when the kidney cells develop mutations, which causes them to multiply out of control. This results in the abnormal accumulation of kidney cells, which grow and form into a tumour. However, like many other cancers, the exact cause of how the DNA of these kidney cells get mutated is still unknown.
What are the common symptoms of Kidney Cancer in Singapore?
Most kidney cancer cases are found by chance, as most people do not exhibit any signs or symptoms in the early stages. But, as the tumour progresses, some typical symptoms include:
- Blood in the urine, also known as haematuria
- Lump in the abdomen, lower back, or side of the waist
- Dull aching pain in the lower back or side of the waist that is not injury-related
- Rapid and unexplained weight loss
- Constant fatigue
- Fever or night sweats
Is Kidney Cancer painful?
Kidney cancer may not always be painful, especially in the early stages when the tumour is small and has not spread. Kidney cancer is often asymptomatic in its early stages.
However, as kidney cancer progresses to advanced stages, it can potentially cause pain or discomfort, particularly in the region of the kidneys.
Remember that pain or other symptoms do not necessarily indicate kidney cancer, as other medical conditions can cause them. However, if you experience persistent symptoms, especially blood in the urine or pain in the flank, make an appointment with Aare Urocare for a proper diagnosis.
Who is at risk of Kidney Cancer in Singapore?
In Singapore, like in many other countries, certain individuals may be at a higher risk of developing kidney cancer.
Risk factors for kidney cancer in Singapore include:
- Age: kidney cancer risk increases with age and is more commonly diagnosed in older adults. The risk of kidney cancer tends to be higher in people over the age of 45 or 50.
- Gender: kidney cancer is more common in men than in women.
- Smoking: people who smoke tobacco are at a higher risk of developing the disease.
- Obesity: being overweight or obese is associated with an increased risk of kidney cancer.
- Family history: individuals with a family history of kidney cancer may have a higher risk.
How is Kidney Cancer diagnosed in Singapore?
To confirm a kidney cancer diagnosis, your urologist will conduct a thorough physical and medical examination, such as an abdomen examination, and check for other symptoms, such as fever. They may also enquire about past medical history, which includes past illnesses and treatments, health habits, and the family’s medical history. Finally, your urologist may order one or several of the following tests as well:
- Blood and urine tests: blood tests and a urinalysis will help identify or rule out other causes of your symptoms.
- Imaging tests: such as ultrasounds, computed tomography scans (CT scans) and magnetic resonance imaging (MRI), may be conducted to check for abnormalities in the kidneys.
- Kidney biopsy: a biopsy may be performed to check for kidney cancer.
What are the treatment options for Kidney Cancer in Singapore?
Treatment options for kidney cancer vary depending on the stage of the disease. These options are:
- Partial nephrectomy: a surgical procedure where the tumour surrounding the kidney tissue is removed, leaving the remainder of the kidney untouched. This procedure is performed if the tumour size is small, the patient is surviving on one kidney, or the patient has impaired kidney function.
- Radical nephrectomy: a surgical procedure where the tumour and whole kidney are removed. This procedure is performed if the tumour size is large or close to the blood vessels or the ureter.
- Radiofrequency ablation: for those who are unfit for surgery, radiofrequency ablation may be done. This minimally invasive procedure involves using thermal energy to destroy tumour cells.
- Active surveillance: if the tumour size is smaller and no medical intervention is required, patients would be advised to undergo active surveillance, where their condition is closely monitored with kidney scans. These scans will help doctors assess and be aware of changes in the tumour.
- Combination treatments: for patients with advanced kidney cancer, a combination of systemic therapy and surgery is often necessary. Systemic treatment may include targeted therapy or immunotherapy.
Frequently asked questions
Kidney cancer can spread to other organs and tissues, including the lungs, bones, and lymph nodes. This is why early detection and treatment are essential to reduce this risk.
Kidney cancer cannot always be prevented. However, you can reduce your risk by quitting smoking, losing weight, and managing high blood pressure.