Common kidney surgical diseases include kidney stone and kidney tumour.
Kidney stone can have different names depending on its locations: renal stone (kidney), ureteric stone, bladder stone or urethral stone. Choice of kidney stone surgery also depends on stone location. Kidney stone usually presents with colicky pain from the back/loin region, lower abdominal quadrant or sometimes radiating to the groin or genital area. Blood in urine can be found by bare eye inspection or urine test. In case of obstruction, the kidney function could be endangered too. Loin pain and fever may clinically represent pyelonephritis, which is an urological emergency that mandates urgent medical attention and kidney stone treatment.
Kidney stone treatment
Kidney stone surgery nowadays rarely requires open operation. Extracorporeal shockwave lithotripsy is one of the most common and least invasive kidney stone treatments. Ureteroscopic (endoscopic) laser lithotripsy can handle obstruction and treat multiple stones in the same session. With the technology advancement, very thin disposable flexible endoscopy can be flexed to 270 degree and used to reach different corners of the kidney. Percutaneous nephroscopic lithotripsy needs a kidney puncture through the skin under imaging guidance. It is used for larger kidney stones such as staghorn stone. Nowadays in kidney stone surgery technology, the instruments are smaller hence reducing the risk of complications. Laparoscopic removal of stone (keyhole surgery) is sometimes indicated for bigger stones which are beyond endoscopic treatment.
Kidney tumours can be divided into benign and malignant tumours. Angiomyolipoma (AML) is the commonest type of benign tumour that needs surgical intervention. When AML size is bigger than 4cm, there is a higher risk of bleeding especially for ladies in child-bearing age. Malignant tumour is usually referred to as renal cancer. Clear cell type carcinoma is most common. In its early stage, the majority of kidney cancers do not present with specific symptoms and are incidental findings during abdominal imaging for other reasons. However, in later stages of disease, kidney cancer may present as loin mass, pain or blood in urine. Thirty percent of patients may present with non-specific symptoms called paraneoplastic syndrome, which is caused by production of chemical signaling molecules by tumour cells. In advanced disease, tumors can grow along major blood vessels and even to the heart. When it spreads, most common sites of metastasis include lymph nodes, lung and brain.
Surgical treatment of kidney cancer
Kidney cancer is a highly curable disease if detected in early stages. Studies show that kidney failure is associated with higher risk of cardiac disease and mortality. Therefore it is advisable to preserve kidney function as much as possible during surgery. It is even more important for patients with baseline or anticipated kidney function impairment, with higher risk of tumour recurrence, or with bilateral disease. In order to achieve that, partial nephrectomy (removal of tumour while preserving majority of normal kidney tissue) is more commonly performed recently. It could be achieved by key-hole surgery, either using laparoscopic instruments or robotic arms. Thermal ablation is another treatment option but associated with higher recurrence rate. Total nephrectomy (removal of one-sided kidney) is mainly reserved for large tumours, with or without tumour thrombus in blood vessels.