What is renal cell cancer?
Renal cell cancer is a cancer of the kidney and is often also called renal cell carcinoma or kidney cancer. In extremely rare cases, children can also develop renal cell cancer. In these specific cases, doctors speak of a Wilms tumour or a nephroblastoma. In Germany, about 5,360 women and 9,280 men develop renal cell cancer every year. Since renal cell cancer hardly causes any symptoms, especially at an early stage, the disease is usually only discovered by chance. Depending on whether the cancer is localised or has already metastasised, it is either surgically removed or treated with targeted therapy or immunotherapy. The 5-year survival rate after the diagnosis of renal cell cancer is about 77 percent.
What is the function of the kidney in the human organism?
The kidney is located behind the peritoneum and has the important function of purifying the blood. Not only are waste products of the metabolism excreted via the ureters. The kidney also regulates the fluid and salt balance as well as the acid-base balance of the human body. Furthermore, the kidney plays a role in vitamin D metabolism and is responsible for the production of a blood-stimulating hormone. Even though it is in principle possible to live with only one kidney thanks to modern dialysis methods, kidney function is essential for life.
What causes renal cell cancer?
Clear cell renal cell carcinoma (RCC) is one of the most common malignant kidney tumours. It usually develops through a ductal system (proximal tubule). However, in addition to clear cell renal cell carcinoma, there are a total of over 50 malignant kidney tumours known to date. However, it is still unclear to doctors why the cells suddenly grow uncontrollably and infiltrate neighbouring tissue through the so-called metastases. Accordingly, the risk factors that favour renal cell cancer cannot be clearly named. However, smoking, being overweight (obesity), lack of physical activity and high blood pressure (arterial hypertension) as well as chronic kidney damage and/or kidney failure are among the risk factors that can favour renal cell cancer. Also, the probability of developing renal cell cancer is 2 to 4 times higher if a first- or second-degree relative already has it. In rather rare cases, renal cell cancer can be traced back to a single gene (Hippel-Lindau syndrome).
How does renal cell cancer manifest itself?
Renal cell cancer is usually discovered by chance, for example during an ultrasound examination, as there are neither targeted early detection examinations nor does the cancer cause any symptoms at an early stage. In rare cases, people complain of rather unspecific symptoms such as fatigue, weight loss or night sweats. Normally, however, only larger kidney tumours cause pain in the kidney area, which can radiate to the back. The lymph nodes may also swell or there may be blood in the urine at this stage. If the cancer has already spread to the bones, some patients also suffer from bone pain.
How is renal cell cancer diagnosed?
If renal cell cancer is suspected, the doctor will first take the patient's medical history and diagnose it using an imaging procedure such as an ultrasound examination (sonography). In order to determine how far the tumour has already progressed, a computer or magnetic resonance tomography will be ordered. Tissue can also be removed with a hollow needle (biopsy), which is examined more closely in the laboratory and is necessary for further therapy planning, as the result provides information about the type of tumour, among other things. If the doctor suspects that the cancer has already spread, an X-ray examination of the chest or a skeletal scintigraphy is carried out. This examines the lungs, but also the bones.
How is renal cell cancer treated?
Renal cell cancer is usually removed surgically. However, the prerequisite for this is that the tumour is limited to the organ and has not yet formed metastases. But the patient's general state of health also plays a major role in surgical intervention.
Surgery does not mean that the kidney is completely removed. Depending on the stage of the cancer and the size of the tumour, only the affected cells are removed and the kidney is preserved. This is sometimes possible with a minimally invasive procedure in which the tumour is removed through small incisions in the skin. An alternative method to surgery is to apply heat or cold sources to the tumour tissue in order to destroy or freeze the cancer cells. However, if the tumour is small, it may be sufficient for the tumour growth to be strictly observed medically. Unlike many other types of cancer, chemotherapy and radiotherapy are not successful in treating renal cell cancer.
Treatment of advanced renal cell cancer
If, on the other hand, the renal cell cancer is already far advanced and has already spread to metastases, doctors will often no longer operate because the cancer cannot be completely removed. Instead, a drug treatment consisting of a targeted therapy and an immunotherapy is used. The first treatment is usually a combination therapy. Since metastatic kidney cancer is incurable, the treatment aims to alleviate the patient's symptoms and improve their quality of life.