In Western industrialized countries, the number of lung cancers has been increasing for years. Although the trend has been declining for men since the 1980s, women have record new sadly high numbers every year. Meanwhile, lung cancer is the third most common form of cancer in both sexes. In Germany, more than 50, 000 people develop lung cancer each year. Even more frightening is his share of deaths: In men, lung cancer is the most common cause of cancer death, in women after all, the third most common.
Smoking as a risk factor
These numbers are all the more tragic, as lung cancer is one of the few malignant tumors where the main risk factor has long been known: around 90 percent of lung cancer patients are smokers.
If you realize that, according to a study meanwhile every third 15-year-old smokes, with Germany is one of the sad front-runners in the international comparison, the likelihood that the number of lung cancer patients will not decline in the future.
What is lung cancer?
Strictly speaking, lung cancer is a generic term for various malignant tumors in the lung and bronchial system. By far the most common form (90 percent) is bronchial carcinoma, which is often colloquially equated with lung cancer and is treated here below. Metastases, ie secondary tumors of other types of cancer, can be flushed into the lungs via the blood and then settle there. Rarely are malignant tumors of the lung and pleura.
Depending on how the tissue appears under the microscope, a distinction is made between small cell (25 percent) and non-small cell lung carcinoma. The latter is further subdivided into various forms, including the squamous cell carcinoma emanating from the covering tissue, which is the most prevalent at around 45%, and the adenocarcinoma, which in contrast to all other forms does not depend on smoking.
The small cell bronchial carcinoma spreads early childhood tumors and therefore has a worse prognosis. For prognosis and therapy, in addition to the microscopic findings of the cell tissue, the tumor stage is also important, ie how large the cancer is and how far it has already spread to surrounding structures and in the body at the time of diagnosis.
What are the causes of lung cancer?
The bronchial carcinoma arises mainly as a result of tobacco smoking. There are about 4, 000 substances found in cigarette smoke, 40 of which are carcinogenic, as well as benzo (a) pyrene, which causes damage to chromosome 9 of a non-cancerous gene P-53. But not only active smoking is unhealthy, even passive smoking increases the risk of cancer. If a non-smoker spends a cozy evening surrounded by smokers in a closed room, such as a pub, the body is burdened as if he had smoked 4 to 9 cigarettes.
The risk of disease increases with the number of cigarettes, the inhalation depth, the duration of smoking and the age. The tar and nicotine concentration also play a role. It is estimated that with 40 pack years (ie one pack of cigarettes a day for 40 years) the cancer risk is increased 30-fold. However, there is good news: if smokers manage to get rid of their nicotine addiction, the likelihood of getting lung cancer is gradually approaching those of non-smokers.
Toxins in the air as a cause of lung cancer
In addition to smoking, other inhaled airborne toxins can cause lung cancer, especially if exposed to it for a long time. These include asbestos, arsenic, chromium, cadmium, nickel, polycyclic aromatic hydrocarbons, mustard gas, uranium, radon, etc. For example, blast furnace workers, gasworks workers, roofers and asphalt makers are at risk, especially if they disregard health and safety regulations. Especially dangerous is the combination of these pollutants with active smoking.
However, why some smokers develop cancer, while others are spared despite decades of nicotine addiction, is not yet clear. A clear hereditary cause could so far no more be found than a diet-related. However, the scientists assume that there are connections.
Lung cancer: symptoms and signs
How is lung cancer expressed? Treacherous is that lung cancer usually causes no symptoms for a very long time. Often, therefore, lung cancer is either discovered accidentally during an x-ray examination or only when it is already advanced and therefore poorly curable. Unlike some other types of cancer, there is currently no screening available that would be suitable as a screening tool for early detection.
When symptoms arise, they are usually at least initially indistinguishable from other lung diseases. The following symptoms should prompt a visit to the doctor, especially if combined or prolonged:
- new-onset, worsening or altering chronic irritable cough
- coughing up blood
- Breathing difficulty until breathlessness
- Breathing sounds while breathing, chest pain
- Lung diseases like bronchitis that do not heal
- Hoarseness, dysphagia
- Fever, night sweats
- Tiredness, performance kink
- Loss of appetite, unwanted weight loss
Further complaints may occur when lung cancer spreads and metastases spread in other organs. The spine, brain, adrenal glands and liver are particularly common, which can cause back pain, headache, dizziness, behavioral changes, abdominal pain or nausea.
How is the diagnosis made?
By means of the examinations not only the tumor is found, but also its kind and its stage are determined in order to be able to decide on the treatment. First, the doctor will ask the medical history, especially smoking habits and occupational risk.
After the physical examination, X-rays of the lungs and various blood tests will follow. In order to be able to assess the tumor tissue, a lung reflection is possibly carried out in which also cell and tissue samples can be taken.
Computed tomography of the ribcage, upper abdomen and brain can be used to determine the extent of cancer and detect secondary tumors. A skeletal scintigraphy can be used to specifically search for settlements in the bone, possibly followed by a bone marrow biopsy. In addition, there are a number of other investigations, which are used depending on the case and before a planned operation.
Which therapy is there?
The treatment depends on the type and spread of the tumor. As much as possible, attempts are made to achieve a cure. However, this only succeeds if all tumor tissue including metastases and affected lymph nodes can be removed. Only then can a recurrence be prevented. Depending on the type of cancer, stage and constitution of the patient, surgery, chemotherapy, radiotherapy or a combination thereof are used.
- Surgery: Right and left lobes consist of three or two lobes, which are composed of a total of ten or nine lung segments. Depending on the size of the tumor, a segment (partial lung resection) or a lobe (lobectomy) is removed, more rarely the entire left or right lung (pneumectomy). With a pulmonary function test, it is determined in advance whether the remaining respiratory activity is sufficient. For an operation especially non-small-celled forms are suitable.
- Chemotherapy: Cytostatic agents are usually given in several cycles, cytotoxic agents that primarily attack cancer cells, but also do not spare the body's own healthy cells. That is why there are often strong side effects. Especially small cell carcinomas respond.
- Radiotherapy: X-rays in certain doses damage cells. Especially small cell lung cancer can be reduced in size, irradiated the skull, can possibly prevent a removal of metastases.
Recently, scientists have discovered new approaches at the molecular biology level, targeting cancer cells in therapy. Initial research suggests that this will open up new treatment options for lung cancer in the future.
What are the course and prognosis?
Overall, lung cancer is currently one of the prognostically unfavorable types of cancer - 5 years after diagnosis live on average only 13 to 14 percent of patients. The prognosis, however, strongly depends on the type, size and spread of the tumor and thus also responsiveness to the therapy, but also on the age and general condition of the patient.
The best prognosis is squamous cell carcinoma at an early stage, the worst is small cell lung cancer. If left untreated, it will kill you even within a few weeks. After completing the treatment, regular check-ups are important so that a recurring tumor can be detected and treated early. And in any case, the person concerned should consistently refrain from cigarettes.