Lung cancer is a malignant neoplasm in the respiratory system (lungs and bronchi). In addition to breast cancer, colon cancer and prostate cancer, it is one of the most common cancers worldwide. Unfortunately, the number of illnesses continues to increase, especially among women.
- Smoking causes 85% of lung cancers.
- Lung cancer is caused by a change in the genetic material due to chronic damage.
- Lung carcinomas can be divided into two groups.
- Because symptoms are unrecognized or misinterpreted, lung cancer is often discovered by accident during examinations.
- The treatment of a lung tumor depends on the type of cancer.
In Austria, around 2,500 men and almost 1,200 women suffer from bronchial carcinoma each year. Thus lung cancer is second only to prostate cancer in males and third in women after breast and colon cancer. Most cases are detected between the 55th and the 65th year of life. However, patients can be significantly younger.
The main risk factor for the development of lung cancer is cigarette smoking: Around 85% of all cases can be attributed to tobacco consumption. Hereditary predispositions or contact with other harmful substances (such as arsenic, radon or asbestos), on the other hand, play a subordinate role. 3-5% of the diseases are caused by passive smoking.
From surgery to Targeted Therapy: Depending on the type and stage, lung cancer is treated differently.
Anyone smoking a pack of cigarettes every day for over 20 years increases their lung cancer risk 30 to 40 times. By contrast, a familial accumulation only leads to a doubling or tripling of the risk.
How does lung cancer develop?
In the cells of the mucous membranes of the bronchi and in the alveoli, there is a change in the genetic material due to prolonged chronic damage (for example, chronic inflammation from cigarette smoke). After a long time, this change means that the normal control mechanisms for the growth and death of cells are no longer effective and a malignant tumor develops. At an early stage of development, this process can sometimes be reversed, such as when the damaging effects are stopped.
Basically, two groups of lung cancer are differentiated:
- Non-small cell lung carcinoma
The non-small cell type accounts for around three quarters of cancers of the lung. It is roughly subdivided into:
- squamous cell carcinoma
- the adenocarcinoma
- the large cell carcinoma
- Small cell lung carcinoma
Small cell lung cancer (about 20% of the disease) spreads rapidly through the bloodstream and lymphatics, but is better for chemotherapy.
This distinction is important from a medical point of view, because the therapy is targeted accordingly.
Which symptoms occur?
In those cases of lung cancer that are discovered at an early stage, these are generally incidental findings: pulmonary x-raying is actually done for quite different reasons, e.g. in case of release for surgical procedures or severe infections suggesting pneumonia.
The most significant problem is that the disease remains asymptomatic for a long time. Often, the typical symptoms, such as coughing, shortness of breath, fatigue or back pain, misinterpreted or ignored. Since the majority of sufferers are smokers with chronic bronchitis and often have cardiovascular problems, the symptoms are attributed to them.
A doctor’s visit is therefore often delayed for a long time. Only the appearance of blood in the sputum or severe weight loss are alarming. More than two-thirds of all cases of lung cancer are therefore diagnosed at a local or systemic (i.e., distant metastasis) stage.
Unfortunately, previous large-scale studies on the possibility of early diagnosis have not shown sufficiently satisfactory results to be meaningful to broad sections of the population. A so-called spiral computed tomography (spiral CT) with low radiation dose is therefore recommended as a preventive check only certain risk groups: chronic smokers over 50 years, especially if at the same time a chronic obstructive pulmonary disease (COPD) is present; in addition, in the case of lung cancer in the family or a workplace that is burdened by inhaled carcinogens (carcinogenic substances). However, the last two factors only seem relevant if the person smokes himself at the same time.
How does the doctor make a diagnosis?
If lung cancer is suspected, the patient is referred to a specialized department where a complete examination is made as soon as possible. Among other things, the stage of the disease, the type of tumor and the spread in the body is examined.
For this purpose, different examination methods such as computed tomography, ultrasound, biopsy or a PET scan are performed.
Which treatment methods are available?
The choice of treatment for lung cancer depends largely on the type of cancer and the stage of the cancer. Treatment options range from surgery to radiation and chemotherapy, to molecular biology therapy.
What is the prognosis for lung cancer?
In contrast to other types of cancer, in the case of bronchial carcinoma, there are no meaningful early detection measures or long-term successful treatment methods. Lung cancer is the only cancer in which the rate of new disease is nearly identical to that of deaths.
Taking all the cases together, current treatment methods achieve a 5-year survival rate of only 15%. However, when early-stage non-small cell lung cancer is detected, around 75 out of every 100 people treated surgically are still alive five years later.
At the same time, lung cancer is virtually the only cancer that has a prevalent and avoidable risk factor. Prevention through smoking cessation is therefore at the forefront.