Kidney Cancer Symptoms

Kidney cancer, i.e. a tumor in the area of the kidneys, often becomes noticeable late and is therefore discovered only by chance in many cases. Possible symptoms are back pain and blood in the urine or non-specific complaints such as fatigue, fever attacks and weight loss. Every year, a good 15,000 people in Germany develop cancer of the kidneys and urinary tract. The majority of those affected are older people between 60 and 75 years of age, and men are more likely to develop kidney cancer than women.

Kidney cancer: what types are there?

There is no such thing as “the” kidney tumor; cancerous tissue can be quite different:

In the kidney, renal cell carcinomas (also called renal carcinoma or adenocarcinoma of the kidney) occur in 95 percent of adults. They originate from the cells of the urinary tubules (tubular system), which are responsible for urine formation.
Oncocytoma, which accounts for about four percent of cases and resembles renal carcinoma on imaging, but does not metastasize, is considered a special form.
Malignant changes in the renal pelvis are much rarer. They do not originate from the kidney cells, but from the mucosa of the urinary tract, and thus resemble the cancers that predominate in the urinary bladder (bladder cancer) and ureters. Their treatment is therefore different from that of renal cell carcinoma.
In addition, malignant tumors can develop in rare cases, which also do not originate from the renal tissue, but develop in the muscles (sarcomas) or originate from the lymphoid tissue (lymphomas).
In children (especially children under five years), Wilms tumors (nephroblastomas) occur predominantly.

Because of the frequency of renal cell carcinoma, the following article discusses only this form of kidney cancer. Cancer: these symptoms can be warning signs

Kidney cancer: causes and development

The possible causes are as varied as the tissue of origin; however, often – as with other types of cancer – no specific triggers are found. In principle, various mechanisms are conceivable, for example, physical, chemical, hormonal, and infectious factors; in the case of kidney cancer, also a hereditary component. In addition, some factors are known to increase the risk of kidney cancer:

By far the most important risk factor is regular smoking. Every day, the kidneys filter harmful substances from the blood, including those that pass into the blood when smoking cigarettes, pipes or cigars. Constant contact with these carcinogenic pollutants doubles the risk of developing kidney cancer. Passive smoking is also considered a risk factor.
High blood pressure appears to increase the risk of developing kidney cancer.
Further risk factor is overweight – especially in women (presumably due to the hormonal shift caused by this); in men, the type of fat distribution probably plays more of a role.
Also, certain lifestyle habits, such as heavy alcohol consumption, regular high-fat diet, lack of physical activity and too little fluid intake (due to reduced flushing of the kidneys and increased concentration of harmful substances) and appear to increase the risk of kidney cancer.
In addition, certain conditions (some congenital), such as cystic kidneys or chronic renal dysfunction, are considered risk factors for the development of kidney cancer. Chronic kidney damage can be promoted, for example, by the long-term use of painkillers.
After a kidney transplant, the risk is also considered increased.
Substances such as halogenated hydrocarbons or cadmium (especially in occupations that are frequently exposed to them) could also play a role.

Symptoms of kidney cancer

Unfortunately, complaints of kidney cancer often appear late and the symptoms are then rather nonspecific. The following signs should be promptly clarified by a doctor:

Blood in the urine: bleeding is not always recognizable as such – sometimes the urine is just darker than usual. Women sometimes mistakenly blame the signs on menopause. Some bleeding can not be detected with the naked eye, but only with the help of test strips.
Rather unilateral kidney pain, that is, pain in the flank and lateral back pain can be signs of kidney cancer, especially also if there is palpable thickening in the area of the kidneys.
Swollen legs may be a symptom of kidney cancer.
New-onset hypertension or blood pressure fluctuations may indicate a kidney tumor.
Nonspecific symptoms that persist over time and for which no cause is apparent, for example, constant fatigue, night sweats, persistent fever, high calcium levels, weight loss and bowel problems may indicate harmless, but also serious chronic diseases.

Often kidney cancer is discovered rather accidentally in the early stages, for example, during an ultrasound examination of the abdomen. Kidney pain: What is the cause behind it?

How is the diagnosis made?

The first step in the diagnosis of kidney cancer is the anamnesis, i.e. the conversation between doctor and patient. This primarily involves asking about current complaints, previous illnesses, and occupational and family stresses. After the conversation, the doctor will perform a thorough physical examination. Depending on the suspicion and for therapy planning, further tests follow. These include, for example:

An examination of urine and blood
Imaging procedures such as an X-ray examination of the urinary tract (urography), an ultrasound examination, a computed tomography or magnetic resonance imaging (CT and MRI), a bone and renal scintigraphy or X-ray imaging of the renal vessels
A cystoscopy
A tissue sampling (biopsy)

Responsible contact is first the family doctor, he can then refer to specialists such as urologists or radiologists as needed.

Stages of kidney cancer

To select the right treatment, it is necessary to determine what stage the tumor is in. This is done using the so-called TNM classification. Crucial are:

The size of the tumor (T)
The involvement of the lymph nodes (N)
Whether metastases have formed (M)

Based on these letters and from numbers, a statement can be made about the extent and size of the tumor (T1 to 4), and described whether lymph nodes are affected or metastases are present (for example, N0 and M1).

In principle, kidney cancer is considered curable, but this probability decreases significantly if metastases have formed, i.e., the tumor has spread.

Renal cell carcinoma: What treatment is available?

If the suspected diagnosis is confirmed, the primary goal is to completely remove the tumor and any daughter tumors that may be present or – if that is not possible – to prevent the tumor from growing and spreading for as long as possible. The preferred method depends primarily on the type of tumor, its size and location. In principle, several methods are available, which can be used individually or in combination: Surgery to remove part or all of the affected kidney, ablation, systemic therapy, or radiation therapy.

Surgery is considered the most important form of treatment and is used when the cancer has not yet spread. Often, the tumor can then be completely removed, thus curing the cancer. However, even after removal of the tumor can relapse.
In a procedure called ablation, the cancerous tissue is destroyed by heat or cold. This procedure is only used for small kidney tumors and when surgery is not possible (such as due to advanced age).
If the tumor has spread, a cure is usually not possible. Then so-called systemic therapy is used to prevent the tumor from further growth and to alleviate discomfort. These include targeted therapy with drugs that attack cancer cells, immunotherapy, in which the body’s own defense cells are stimulated, and supportive therapy methods aimed at alleviating symptoms.
Radiation therapy is only used if the cancer has already metastasized. A cure is not possible through radiation.
Chemotherapy is not suitable for the treatment of kidney cancer.

Active Surveillance or Active waiting is when (especially in older patients with serious pre-existing conditions and if the tumor is very small) is initially waived therapy and one continues to monitor the development of the tumor. Since kidney tumors usually grow very slowly in old age, in such cases it is weighed up whether those affected are still expected to endure the risks and strains of surgery.

Aftercare: what to look out for after treatment?

Immediately after treatment, affected individuals can take advantage of rehab (medical rehabilitation). In addition to exercise therapy and various counseling services, patients also receive psychological care there. It is important that patients attend regular follow-up examinations. This is the only way to monitor the course of the disease and, in the event of a relapse, to intervene therapeutically again at an early stage or to adapt the treatment. If the disease progresses without complications, the check-ups take place at intervals of a few months during the first two years, then every six months and later once a year. It is recommended that patients stop smoking and generally maintain a healthy lifestyle. Further measures depend on the individual clinical picture and the treatment carried out.

What is the course and prognosis?

Individual survival rates vary widely and depend not only on the type and location of the malignant change, but also on the time at which the tumor is detected. Cancer in the kidney area often shows up very late and is therefore often detected only incidentally during abdominal examinations at an early stage. A general prognosis or statements on life expectancy are therefore difficult to make. If the tumor is detected early, while it is still confined to the kidney, the 5-year survival rate is about 70 percent or higher if the tumor is very small. If, on the other hand, the lymph nodes are already affected, a 5-year survival rate of about 20 percent is assumed. Nevertheless, the average survival rate is quite high compared to many other cancers. Bladder cancer: early detection test for women