What is Lung Cancer? Symptoms and Treatment

Lung cancer, which ranks first among the cancer diseases that result in death worldwide, is one of the serious public health problems that causes the death of more than 1.7 million people every year. Signs and symptoms that occur in the initial stages of the disease often go unnoticed, and important symptoms such as cough are largely overlooked, especially in smokers. This causes lung cancer to be detected in very late stages and the chance of treatment is greatly reduced. Having accurate information about lung cancer, being able to recognize the symptoms that occur in the early stages, and applying for screening programs at regular intervals in the presence of risk factors are extremely important in order to diagnose and treat lung cancer correctly.

What is lung cancer?

There are basically two different types of lung cancer: small cell lung cancer and non-small cell lung cancer. The clinical features of the disease, the biological behavior of cancer cells, and the treatment principles for the disease vary greatly depending on the type of lung cancer.

80-85% of lung cancers are non-small cell lung cancer. These cancers can occur in three different ways: adenocarcinoma, squamous cell lung cancer and large cell cancer. The most common lung cancer in our country, as well as all over the world, is adenocarcinoma, and it is observed more frequently in women, younger ages, and non-smokers. Squamous cell cancers constitute 25-30% of non-small cell lung cancers. These tumors, which are more centrally located, are more associated with smoking. Large cell cancers are responsible for approximately 15% of lung cancers.

Small cell lung cancer occurs in 10-15%. Smoking is again the most important factor in the formation of this type of tumor. Small cell lung cancer tends to spread and multiply rapidly. Due to these features, although they are sensitive to chemotherapy and radiotherapy, disease recurrence can often be observed in many patients.

Other rare lung cancers: They can be listed as carcinoids, adenocystic carcinoma and sarcomas.

What are the types of lung cancer?

Lung cancers according to the type of cell causing the cancer:

1. Squamous cell carcinoma
2. Adenocarcinoma
3. large cell carcinoma
4. Adenosquamous carcinoma
5. Sarcomatoid carcinomas
6. Neuroendocrine Tumors (Small cell carcinoma, others…)

Symptoms of lung cancer

Many lung cancers may not show symptoms until they spread. The fact that the complaint of cough, which is one of the first symptoms, is accepted as a normal condition by smokers, further delays the detection of the disease at an early stage. Knowing the symptoms that occur with lung cancer is extremely important in order to detect cancer at an early stage. Common symptoms in case of cancer are as follows:

Cough

Cough is the most common symptom with lung cancer. 75% of patients encounter a common cough problem in the initial stages of the disease, but the majority of them do not consider this as an abnormal situation because they complain of cough caused by smoking. For this reason, the cough symptom seen in the initial phase is often overlooked.

Shortness of breath

A mass that develops with cancer may cause airway stenosis, edema in the lung lining, and loss of movement in the diaphragm muscle. All these conditions lead to complaints such as shortness of breath and difficulty breathing, called dyspnea.

chest pain

Even though the lung tissue lacks the sensation of pain, pain may develop in areas where tumor cells spread. When lung cancer metastasizes to the chest wall or to the nerve cell group called the brachial plexus in the armpit area, the person may complain of chest pain and pain in the upper arm or shoulder.

sudden weight loss

As with all cancer diseases, sudden weight loss occurs in lung cancer. However, this may be a symptom that often occurs in the later stages of cancer or in the presence of liver metastases.

hemoptysis

Bloody cough, medically called hemoptysis, is one of the important symptoms seen in some lung cancer cases. It usually occurs as a result of the tumor spreading to the upper respiratory tract.

Recurrent lung infections

Recurrent or non-healing pneumonia attacks, especially in people with long-term smoking, may be a sign of lung cancer.

To which organs does lung cancer spread?

Lung cancer can spread (metastasize) to organs and tissues such as the brain, bone, liver, digestive system, membrane surrounding the lung, pericardium, adrenal gland, skin and soft tissue.

What are the causes of lung cancer?

1. Cigarette: 80-90% of lung cancer patients have a history of smoking and it is one of the factors that increase the risk of lung cancer. The risk of developing cancer; The age of starting smoking, smoking duration, type of cigarette smoked (e.g. filtered, unfiltered, cigar, low tar and nicotine content, etc.) and the amount of cigarettes consumed daily are affected. It increases the risk of cancer 10-30 times compared to non-smokers. This risk increases significantly, especially after 20 packs/year. Exposure to secondhand smoke likewise increases the risk of lung cancer. Cigarette smoking has been directly associated with lung cancer in 90% of women and 79% of men. Quitting smoking does not completely eliminate the risk of cancer, but it does reduce the risk.
2. Environment: Industrial and environmental factors are important for the development of lung cancer. A relationship has been established between exposure to substances such as radon gas, asbestos, air pollution, radioisotopes, heavy metals and mustard gas and lung cancer.
3. Genetic: It is suggested that hereditary factors are effective in the development of lung cancer. If there is a family member with lung cancer, the risk of developing it increases 2.4 times.
4. Viruses: Lung cancer is more likely to occur in people with HIV infection.
5. Radiation: Radiation from any source can damage the lung tissue, causing deterioration in the structure of bronchial cells and carcinogenesis.

How does lung cancer occur?

When cells in the respiratory tract are exposed to cancer-causing factors for a long time, some mutations may develop in lung bronchial cells. These chronic exposures can cause cancerous changes in cells through a series of mutations. These types of abnormal cells can develop in anyone, but an adequate immune system recognizes and eliminates or repairs these cells. As a result of a weakness in the organism’s immune system, these cells, whose structure is damaged, increase in uncontrolled proliferation and cancer masses form. Again, with the development of other changes in its biological structure, it acquires the feature of metastasis and begins to spread to distant organs.

How is lung cancer diagnosed?

Definitive diagnosis of lung cancer is made by imaging the tumor. A general opinion is formed in line with the important points in the patient’s history and the findings detected in the clinical examination, but these symptoms must be supported by laboratory and radiology examinations. The main tests used for the diagnosis of lung cancer are direct radiography, computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET), bronchoscopy, transthoracic fine needle aspiration biopsy, mediastinoscopy, thoracoscopy, video-assisted thoracic surgery (VATS). and thoracotomy.

For diagnosis, direct radiography is first used, and some images indicating the disease such as lung nodules, infiltration, hilar fullness, atelectasis, mediastinal opening, presence of fluid in the lung membrane, and increased regional transparency can be detected. After this, computed tomography of the lung is used as a second examination and important findings such as the general structure of the lesion causing the mass, its cellular distribution, hilar and mediastinal involvement, and lymphadenopathy in this region are obtained. In the later process, other imaging methods deemed necessary by the physician may be applied to determine important points such as staging the disease, determining the preferred treatment method, and detecting organ involvement.

Lung cancer treatment methods

In order to choose the treatment method appropriate for the patient and the disease in lung cancer, the cancerous cell type must first be determined and the cancer stage must be accurately defined.

The most definitive treatment method for early stage non-small cell lung cancer is surgical removal of the cancerous mass. Necessary opportunities should be evaluated for all cancer patients at a stage that can be operated on, and the first focus should be on removing the mass by surgical operation. Later, depending on the stage of the disease, methods such as chemotherapy (drug therapy), immunotherapy or smart drugs and radiotherapy (radiation therapy) may be added to the treatment.

In small cell lung cancer, treatment in the early stages includes the combination of chemotherapy and radiotherapy. Surgical treatment has a very limited place in this tumor.

Lung cancer screening methods

In a study conducted among patients over the age of 55, defined as the high-risk group, who smoked heavily (30 packs/year) or smoked at this intensity and quit at most 15 years ago, they were evaluated according to lung x-ray and scanned with low-dose lung computed tomography (CT). A 20% decrease in the death rate due to lung cancer was found. According to these results, annual low-dose CT screening is recommended in the high-risk group. However, it should be noted that the recommended tomographic scan will never replace smoking cessation.

What are the stages of lung cancer?

Lung cancer is divided into four stages.

Stage 1: The tumor is only in the lung.

Stage 2: Cancer has spread to the lymph nodes near the lung.

Stage 3: The tumor has spread to the pleura or the mediastinal space between the two lungs.

Stage 4: The disease has spread to distant organs such as bones, liver, adrenal gland and brain.

Staging of lung cancer is necessary for treatment planning. If lung cancer is detected in the first or second stage, the success rate in treatment is higher. Tumor cells in the lung tissue are surgically removed and preventive treatment is planned according to the doctor’s decision. If the disease is in an advanced stage; Methods such as chemotherapy, targeted therapies, immunotherapy and radiotherapy are determined by the doctor according to the cell type and stage.

What are the chances of cure for lung cancer?

The course of the disease in lung cancer varies depending on the cell type of the tumor, the stage of the disease, the findings detected when diagnosed, the size of the tumor and the rate of spread of the disease.

In the majority of early stage lung cancer cases in which no metastatic disease is detected, there is a chance of recovery with surgical treatment and, if necessary, complementary radiotherapy and chemotherapy. Although significant advances have been made in treatment methods for advanced disease, the probability of relapse is higher. Long-term chemotherapy, targeted therapies or immunotherapies can provide long-term control of the disease in these stages. However, due to the risk of resistance to treatments and progression, radiological checks are required at regular intervals. As a result, survival is higher in cancers that are detected at an early stage and can be surgically removed.