Lung cancer
Cancer Definition
It is used for a wide variety of diseases, all of which have one thing in common: The uncontrolled breakdown of cells of an organ or tissue. As a result, a tumor (tumor) is formed. Malignant tumors go out of the normal growth control of the organism. Over-the-counter cells proliferate in an unrestrained manner. They penetrate the surrounding tissues, grow in them and destroy it, can enter the blood vessels and lymphatic vessels, reach other body organs by blood flow and lymph flow. The cells of resistant tumors can migrate to other organs and reproduce – thereby forming sister tumors (metastases) that resemble resistant tumors. Lung cancer is one of the cancer types defined as resistant tumor. Cells of blood cancer types spread throughout the body along with the blood. Some types of these also form knots and tubers, which are very similar to durable true tumors.
Lung cancer forms
When the tumor tissue is examined under the microscope, it is determined that there are essentially four types of bronchial carcinoma (lung cancer). The most common types are plate epithelial carcinomas originating from epithelial (secretory) cells and adeno carcinomas originating from glandular cells, with a total incidence of 70 to 75 percent. Approximately 20 percent of tumors are of the small cell carcinoma (lung cancer) type. In addition to these, large cell carcinoma (lung cancer) and other rare lung cancers are seen at a rate of 10%. But for treatment planning, a distinction is made only between non-small cell and small cell lung cancer (bronchial carcinoma) groups. In the non-small cell lung cancer group, adeno carcinomas, plate epithelial carcinomas, and large cell carcinomas are aggregated. However, it is expected that subtypes of lung cancer can be characterized and handled separately in the future, especially with the help of improving molecular biology methods in this field. Based on this, it is hoped that treatment options adjusted to the biology and growth regulation of the tumor will be achieved.
Benign tumors can also form in the lung, for example from fibrous connective tissue, cartilage tissue or improperly formed tissue. But these are very rare and are below 10 percent. One sign of benign tumors is that they usually grow slowly and compress healthy tissue in situ, but do not kill or destroy them.
Causes and Risk Factors
It is likely that many factors affect the formation of lung cancer together. But some factors that increase the risk of personal illness are well known.
If a person who smokes a lot gives up this habit, the risk of getting sick within 10 years after quitting smoking decreases from 15 times to 5 times compared to a non-smoker. 15 years after quitting smoking, this risk is only twice that of a non-smoker. This risk decreases even more rapidly in women.
Environmental Factors: Contacting and breathing various chemicals may mean an increased risk of lung cancer, especially in direct proportion to smoking. Asbestos, arsenic, chromium, nickel, radon and aromatic hydrocarbon are some of these substances and play an important role in the protection of workers. The fact that the air outside contains very high levels of harmful substances can slightly increase the risk of lung cancer by about 50%. Among the important factors in this regard, soot and other fine dust generated by Diesel fueled engines can be counted. Nutrition Nutrition is important, especially eating enough fruit obviously protects against lung cancer. But taking vitamin tablets or other food supplements instead of fruit does not replace this protective effect. In particular, smokers should be especially careful with such substances: In fact, in studies conducted to show the protective effect of some vitamins, even an increased risk has been found in smokers when vitamin tablets are taken.
Genetics: The heredity factor understood also plays a role in the development of lung cancer. How important this is and how often it actually affects the development of lung cancer is still largely unclear. In this regard, some gene changes have been identified that possibly make people more sensitive to certain harmful substances and increase the risk of disease. Here, too, there are smokers in particular.
Risk Groups: The biggest feature that distinguishes lung cancer from other cancers is that it is preventable. In approximately 90 percent of lung cancers, the diseases are associated with known causes. About 85 percent of these are linked to smoking. In professional life, people can take the most precautions against lung cancer by adjusting their behavior accordingly and taking preliminary measures. The lack of screening test in early diagnosis brings prevention measures to the fore.
Diagnostic Methods
- bronchoscopy
In case of suspected lung cancer, one of the most important diagnostic methods is bronchoscopy. The meaning of bronchoscopy is the use of an optical instrument called a bronchoscope, which can be inserted into the bronchi and their branches through the trachea and enables the visualization and examination of those regions. With these it is even possible to penetrate bronchial branches with a diameter of several millimeters. Patients are given a sedative drug and the mucous membranes of the nose, throat, larynx and great bronchi are locally numbed using a spray. The bronchoscope instrument is inserted through the mouth. In some special cases, for example, if a tumor is narrowing the bronchi, a rigid bronchoscope is used. In this discretion, the examination is always performed with full anesthesia. A biopsy is performed with the help of a forceps passing through the bronchoscope. This means taking tissue samples from suspicious areas of the bronchial walls. Tissue sampling from the primary lung tissue is performed through a needle inserted through the bronchial wall. Suspicious tissue samples taken are subjected to pathological examination. If it is cancer, its typing, that is, the exact characteristic of the tumor type, is determined. The method of washing the bronchi, called ‘bronchial lavage’, or the samples taken by rubbing from the bronchial wall, allows to obtain individual cells that are removed from the tissue for microscopic examination. This type of examination is called cytological examination, and with this method, cancer-specific changes in the tissue can be detected. In more than 70 percent of patients, it is possible to reach a diagnosis based on tissue and cell samples taken. For example, if it is not possible to reach a suspicious area in the outer parts of the lung with the bronchoscope, a biopsy is performed by entering the chest wall from the outside with a thin needle. Under CT control, a long and thin needle is inserted into the suspicious area and some tissue is sucked out. This method has been used frequently recently. There are no complications if the application is done by an expert in accordance with the procedure.
- Defining the prevalence of the disease
If the suspicion of bronchial carcinoma is confirmed and the type of tumor is determined histologically or cytologically, metastasis of the disease (whether it has spread from the place of origin to other sites) is investigated. For this purpose, especially the regions and organs where metastases of lung cancer are located are examined. These are mainly the liver, adrenal glands, bone, lymph nodes in the mediastinum, and the brain. CT (computed tomography), Bone Scintigraphy and Ultrasound can be done. This method is used in most cases for the detection of disease as well as for the detection of the exact distribution of a lung cancer. This examination covers the entire chest and upper abdomen and provides examination of the liver, adrenal glands and lymph nodes. The device’s computer calculates cross-sectional images of each area. Tumors can still be detected even if they are smaller than 5 millimeters. In some cases, an additional ultrasound examination may be necessary. MR should be used in special cases (invasion of the mediastinum, large vessel involvement, posterior sulcus tumors and chest wall spread).
- mediastinoscopy
In most cases, the cells of lung cancer are transported to other regions via lymphatic vessels. In frequent cases, these cells are collected in lymph nodes in the mediastinum region; is seen. Imaging of the mediastinum region (Mediastinoscopy) is appropriate, especially if the lymph nodes are seen to be enlarged on computer tomography (the short axis is greater than 1 cm), and if the therapy to be applied and whether an operation should be performed depends on the condition of these lymph nodes. For this, the tissue is cut just above the breastbone under anesthesia and a probe called a mediastinoscope is inserted into the area between the lung wings. With this method, an opinion is reached about whether there is a tumor in that area. It is discussed in a separate section on our website. Positron Emission Tomography, abbreviated as PET, provides information about the metabolism movement in the tissues. PET is more successful than CT, especially in imaging the lymph nodes of the area called the mediastinum, located between the heart and the lung. If the PET examination gives a negative result, it is very likely that the lymph nodes have not been involved. If PET is positive, tissue diagnosis is needed. PET-CT device, which combines the positive aspects of PET and CT methods and applies them in a single procedure in combination, gives more successful results, especially in terms of anatomical location. This method is currently used in a small number of treatment centers. This method has entered the field of routine diagnostic use.
Staging
- Searching for metastases
Especially in the case of small cell lung cancer or regionally advanced non-small cell lung cancer before the planned operation, a computer tomography of the brain with the help of contrast material or a bone scintigraphy may be appropriate. MR is valuable, especially in patients with symptoms of brain metastases, if CT (computer tomography) has not yielded any findings. If bone metastasis is suspected, a bone scintigraphy is performed. Technetium (a metallic element), which is given to the blood vessels with a solution due to phosphate, accumulates in the bones that are sick. The concentrations of this element can be viewed on the body with the help of a special camera, because the used technetium radiates for a short time. However, since the bone scintigram shows increased bone metabolism, including benign changes, an X-ray examination or MRT examination is necessary for a more reliable diagnosis. PET is very valuable in bone metastases. If staging is to be done with PET, other examinations are unnecessary.
Control of general health status Before performing an operation, a decision should be made whether the general health status of the patient is suitable for a surgical procedure and to what extent the lung tissue will be excised or radiotherapy applied. Examination for this purpose includes careful investigation of respiratory function and an electrocardiogram (ECG). In lung function tests, one second volume and total capacity are the most important data in active exhalation.
Disease Stage: The examinations described above take into account the extent, size and local (regional) spread (T), lymph node recurrence (N,Nodule) and metastases (M) of the tumor according to the tumor TNM system. The numbers behind the letters give information about the size and distribution (T1-4), the number and position of diseased nodes (N0-3) and distant metastases (M0 or M1) with or without. For example, T1 N0M0 means a small tumor that has not spread to lymph and has not metastasized. The stage of this disease determines the type of treatment. The definitive determination of the TNM stage is only possible after surgical removal of the tumor. In this case, the pathologist’s report includes a lowercase “p” for the TNM stages and means pathologically proven, for example pT1pN0pM0. Treatment planning The type of cancer, the stage of the disease, and the patient’s general health score determine the treatment. It is also very important whether the lung cancer is small cell or not. In non-small cell cancer, surgery should be performed if possible, in small cell lung cancer, surgery is performed in Stage Ia. It is possible to treat with rays, that is, with radiotherapy and by using drugs that inhibit cell growth, in other words chemotherapy. These are applied either alone or in addition to the operation method, depending on the situation. Chemotherapy is given priority in small cell cancer. If the general health of the patient is not good, especially if the efficiency of the heart and lungs is weakened, some forms of therapy can only be applied to a limited extent or not at all, otherwise they will be very tiring for the patient with lung cancer. The physiological age of the patients does not actually play an important role in this regard. Chronological age does not constitute a contraindication for surgery, that is, it is not an obstacle to surgery. Lung cancer treatment should be performed by experienced clinicians and physicians.
Treatment
If local cancer is identified in staging studies, if the patient’s general condition and especially heart and lung function are suitable for a surgical intervention, the option of operation is always at the forefront in non-small cell lung cancer. On the other hand, the option of operation in small cell lung cancer is not in the foreground, except at the very early stage.
The aim of the operation is to remove the tumor completely (it is a complete resection) by taking together the healthy lung tissue around the tumor. Lung lobes, lymph nodes in the hilar and mediastinum region that become ill within the scope of the operation are also scraped (lymph node dissection) and subsequently examined for tumor. In order to be complete, there should be no tumor in the border areas of the lymph node farthest from the tumor. The most common type of operation is cutting out the affected lung lobe (Lobectomy).
If the tumor has crossed the border between the two lobes, both lobes are cut and removed (Bilobectomy). In large tumors in the main bronchus region (central, central) near the lung entrance, one of the lungs can be removed (pneumonectomy). However, due to the higher risk of operation and the effects of pneumonectomy, this surgical procedure should only be performed in carefully planned and planned situations.
Organ-sparing operation (Sleeve Resections): Today, lung surgeons perform operations to preserve as much of the lung tissue as possible. If there is healthy lung tissue behind the tumor in a central part of the lung and the nutrition of this tissue is to be cut as a result of the operation, the ends of the cut bronchi and possibly the great blood vessels can also be reattached and sutured (bronchoplastic operation and angioplastic operation). In this way, the remaining lung parts are fed with air and blood again and their functions can be maintained. If the tumor has spread to the organs and tissues adjacent to the lung, these are also surgically removed. In the absence of spread to the lymph node, chest wall, aorta, diaphragm and caval vein resections and constructions can be performed. It has been examined separately under the title of Extended Lung Surgeries on our site. How the situation really is and what width of operation should be performed can only be seen during the surgical procedure. Recoverability of residual lung A slightly damaged lung before surgery, removal of lung tissues; The reduction of the breathing surface due to functional surface loss can be compensated to a certain extent, although the number of cells does not increase, it provides this with surface increase due to the expansion feature of the lung. The remaining lung tissue expands to compensate for the lost part, and thus, severe shortness of breath usually does not occur after the operation. .
