Kidney TumourUro-Oncology Unit
There are several types of malignant kidney tumours that are collectively known as renal cell cancer. In recent years, through the development and use of imaging tests such as ultrasound of the urinary system and CT, the number of diagnoses in early stages has increased, achieving improvements in the survival. In addition, nephron-sparing surgery (or partial nephrectomy) allows removing only the tumour, preserving the organ for the most part and providing a higher quality of life for the patient in the long term.
Kidney tumours represent 2-3% of all adult cancers. It predominates in men in the sixth-seventh decade of life and is clearly related to tobacco use (multiplying up to 2.5 times the risk of kidney tumour in patients who smoke). Other risk factors include obesity, hypertension, end-stage renal failure and having first-degree relatives with kidney cancer. Other possible risk factors have been described (such as exposure to carcinogens, dietary habits, non-steroidal anti-inflammatory drugs, etc.) but with inconclusive data. The best prevention method is to avoid tobacco and obesity.
There are several types of malignant kidney tumours, the most frequent being the clear cell carcinoma (70-80%), the papillary tumour (10-15%) and the chromophobe tumour (3-5%).
More than 50% of kidney tumours are diagnosed incidentally, that is to say, they are found through diagnostic tests carried out for another reason, since they rarely produce symptoms. Symptoms appear due to the tumour growth. The classic symptom triad includes pain, appearance of an abdominal mass and haematuria. Retroperitoneal bleeding or paraneoplastic syndromes may also occur.
- Urologists highly specialised in kidney cancer.
- Ultrasound of the urinary system.
- Kidney biopsy (guided by ultrasound or CT scan).
- Radiodiagnostic service: CT, NMR and PET.
Imaging tests are essential for diagnosis.
- The ultrasound is a safe test that allows the diagnosis of solid renal masses and differentiates them from cystic lesions.
- The multiphase CT should be performed in all cases to characterise the renal mass, evaluate the neighbouring organs and extension at distance.
- Magnetic Resonance Imaging is used in cases of diagnostic doubt, in cases of complex cystic lesions, if the patient has allergy to iodinated contrast agents or to evaluate the possible infiltration of the renal vein and vena cava.
The percutaneous renal biopsy, guided with ultrasound or CT is necessary in some selected cases: diagnosis of suspicious renal masses in imaging tests, tumours that are not going to be subjected to surgery (monitoring or ablative therapies) or in metastatic tumours in which it is necessary to know their histological lineage to adapt the chemotherapy or immunotherapy treatment.
There are a number of poor prognostic factors that can help us predict the course of the disease: local or distant spreading (metastasis), high nuclear histologic grade (Furhman’s grade), onset of symptoms, anaemia, ESR, high alkaline phosphatase or high LDH.
- Surgery: Open and laparoscopic/robotic radical nephrectomy
- Surgery: open partial laparoscopic/robotic nephrectomy
- Surgery for renal tumour with vena cava thrombosis.
- Robotic surgery.
- Renal mass embolisation (interventional radiology).
- Close collaboration with the Medical Oncology and Radiotherapy services.
In the treatment of kidney cancer, a distinction must be made between a localised tumour and the metastatic cancer:
» Nephron-sparing surgery or partial nephrectomy:
Consists in removing the entire kidney tumour, preserving as much of the organ as possible to avoid later renal failure. Achieves rates of 80-100% 5-year disease-free survival. It is the treatment of choice, whenever technically possible, for tumours smaller than 7 cm. It should also be performed in patients with tumours in both kidneys or in patients with only one kidney. This surgery can be performed with an open, laparoscopic or robotic approach, depending on the characteristics of each case.
» Radical nephrectomy:
It consists in removing the entire kidney, respecting the adrenal gland (unless it is infiltrated by the tumour). Lymphadenectomy, or exeresis of the lymph nodes near the kidney, is performed if imaging tests reveal involvement or in cases of poor prognosis. As with the partial nephrectomy, it can be performed with an open, laparoscopic or robotic approach, depending on the characteristics of each case.
» Active monitoring:
Close surveillance of the tumour may be applied on elderly patients who are not suitable for surgery and with tumours smaller than 3 cm.
» Ablative therapies:
Radiofrequency or cryotherapy; application of energy to the tumour (laparoscopically or percutaneously). It can be performed on elderly patients who are not suitable for surgery and with tumours that are smaller than 3 cm.
Locally advanced or metastatic tumours
» Nephrectomy of renal tumour with vena cava thrombosis:
When the tumour progresses locally, thrombus may appear in the renal vein, or even in the vena cava, with a tumour component. In these cases it is necessary to perform the nephrectomy and exeresis of the entire tumour thrombus, sometimes requiring the collaboration of cardiac surgeons. This is a high-risk surgery that must be performed in specialised and experienced centres, being our unit one of them.
» Cytoreductive nephrectomy:
This nephrectomy is performed in cases of metastatic kidney tumour with the intention of curing the patient or prolonging survival, combining surgery with systemic therapies.
» Systemic therapies:
Chemotherapy is of little use in treating renal tumours. However, immunotherapy and drugs aimed at preventing the blockage of the immune system have great benefits for survival.