Kidney Cancer

Kidney cancer — most commonly renal cell carcinoma (RCC) — is a malignant tumour that arises from the cells of the kidney. Many cases are diagnosed at an early stage and are potentially curable. A significant proportion are discovered incidentally on imaging performed for unrelated reasons (an ultrasound or CT scan done for another symptom). Staging follows the TNM system, and treatment depends on tumour size, location, patient factors and stage.

Small kidney tumours are usually symptom-free because the kidney sits deep in the abdomen and can accommodate a growing tumour without pressing on other structures. When symptoms do occur, they can include visible blood in the urine (haematuria), a persistent flank or loin pain, a palpable abdominal or flank mass, unexplained weight loss, fatigue, persistent low-grade fever, or anaemia. Because early-stage disease is usually silent, the majority of kidney cancers are now detected incidentally on scans done for other reasons.

Established risk factors include smoking, obesity, and high blood pressure. A family history of kidney cancer or inherited syndromes such as Von Hippel-Lindau, hereditary papillary RCC and Birt-Hogg-Dubé also carry a higher risk. Long-term dialysis or advanced chronic kidney disease increases the likelihood of developing acquired cystic disease of the kidney and associated tumours. Occupational exposure to trichloroethylene is a rare but recognised risk.

Diagnosis is usually made on imaging — a CT scan with contrast is the staging gold standard, showing the tumour size, location and any spread to adjacent structures or the renal vein. An MRI may be used where CT contrast is contraindicated, or for particular tumour features. In selected cases — typically small renal masses under 4 cm — a percutaneous renal biopsy is performed under CT or ultrasound guidance to characterise the tumour before deciding treatment.

Partial nephrectomy (nephron-sparing surgery) removes the tumour and a small margin of healthy tissue, preserving the rest of the kidney. This is the preferred approach for smaller tumours (typically T1) where technically feasible, because it preserves long-term kidney function. Radical nephrectomy removes the entire kidney and is used for larger tumours, tumours in difficult locations, or where partial surgery would not be safe. Both are typically performed robotically at LUS, which offers faster recovery, less pain and shorter hospital stays than open surgery.

Cryoablation (freezing) and radiofrequency ablation (RFA) (heat) are image-guided, minimally invasive alternatives to surgery for selected small renal tumours (typically under 4 cm). A thin probe is passed through the skin into the tumour under CT or ultrasound guidance, and the tumour is destroyed by extreme cold or heat. Ablation is particularly useful for older patients, patients with a single functioning kidney, and those with medical conditions that make surgery high-risk. Recovery is fast, but ablation is not suitable for larger or centrally located tumours.

Yes — in selected cases. Active surveillance can be appropriate for small renal masses (typically under 3 cm) in older patients or those with significant medical comorbidities where the risks of surgery outweigh the risks of the tumour itself. It involves regular imaging (usually every 3–6 months initially) to monitor tumour size and growth rate. Definitive treatment can then be offered if the tumour shows meaningful growth or if patient factors change. Many small renal tumours grow very slowly.

The outlook depends primarily on the stage at diagnosis. For early-stage kidney cancer (T1, confined to the kidney), 5-year survival is typically over 90% following surgery or ablation. Larger tumours (T2–T3) or those with local spread carry a lower but still favourable outlook. Long-term follow-up with periodic imaging is important because kidney cancer can recur years after treatment. Advanced or metastatic kidney cancer has been transformed in recent years by targeted therapies and immunotherapy, which have significantly extended survival.