Lung cancer is a malignant tumor starting point of glandular bronchial epithelium. It is most commonly located in the right lung, in large bronchi and upper lobes. It can be primary or secondary.
Primary lung cancer – is the most common cancer in the world. smoking is the leading cause of lung cancer primitive. Even passive exposure to tobacco smoke is carcinogenic: for a non-smoker living among older smokers, the risk of a primitive lung cancer is 35% greater than the risk to a nonsmoker not exposed to tobacco smoke. Environment (air pollution but not exposure, professional or not, to radiation or certain materials such as asbestos, chromium, nickel, polycyclic) is another risk factor.
Are distinguished two types of primitive lung cancers, depending on the size of their cells.
- Said cancer “, other than small-cell” grouping epidermoid tumors (45%), adenocarcinoma (20%) and large-cell undifferentiated cancer (15%). These cancers manifested by respiratory signs (cough, dyspnea, chest pain, bloody sputum, whistling breathing, lung abscess, purulent pleurisy), which are associated with later alteration of the general state of the subject.
- Small cell cancers with high metastatic potential and early mediastinal invasion are particularly serious. Their manifestations are similar to those of cancer “other than small cell”. Due to the volume of tumors and their proliferation, sometimes appear dilated superficial veins of the chest and neckline edema in case of superior vena cava compression, and a paraneoplastic syndrome (especially Schwartz-Barter’s syndrome, caused by abnormal secretion of ADH by malignant tumor).
The discovery of a primitive lung cancer occurs generally during a radiological examination prescribed because of symptoms described above. The tissue (biopsy, performed generally by fibroscopy bronchitis) or cancer cells (by sputum analysis) allow confirmation of the diagnosis. After a locoregional evolution, primitive lung cancers can work extrathoracic metastases, of which the most common are bone and liver brain.
Treatment of cancers “other than small cell” depends on their scope in the chest, just outside of (metastases), and respiratory function status of the subject. At the end of this balance, only 30% of patients are operated. Among these, 25% can benefit from a complete eradication of cancer, ablation can be done for a segment of the lobe, a whole lobe (lobectomy) or an entire lung (pneumonectomy). Radiation does not stop tumor extension than a very small number of cases. Regarding chemotherapy, they give mediocre results.
Treatment of small cell cancer is based on combination chemotherapy (making use of several drugs). It is desirable that it be associated with radiotherapy to the chest where localized forms. It comprises mainly tobacco control and occupational safety measures.
Secondary lung cancer (metastasis bronchopulmonary)
Because of the rich vascularity of the lung, these cancers are very common. They are due to metastases, more often the lung and bronchial, arising either by blood or by the lymphatic from a primitive cancer whose headquarters is variable, most often located breast, digestive tract, kidney or bronchi.
Ttheir symptoms are the same as the primitive lung cancers. At radiography, secondary lung cancers can take many different aspects.
Treatment depends mainly on the nature of primitive cancer, in exceptional cases, treatment may be surgery. Their prognosis is generally severe.