Lung cancer

Lung cancer is a malignant or benign tumor mass that forms in the lungs.

This mass expands over time and leads to:

  • organ failure: the tumor blocks the normal flow of air in the lungs;
  • Metastases: the tumor spreads to other organs of the body.

Cancer endangers the entire human body.

Lung cancer can form in the cells of:

  • Bronchia
  • Bronchioles
  • Alveoli.

Tumor growth determines the increase in cells in the affected region.

It is important to determine the stage of lung cancer in order to be able to assess the damage.


Types of lung cancer

Over 90% of primary tumours develop in the bronchi, one of the two main branches of the trachea. This is called bronchogenic carcinoma.

Lung cancer
Lung carcinoma includes malignant neoplasms (neoplasms) in the epithelium of:

  • Bronchia
  • Lung tissue.

This type of tumor represents more than 95% of malignant lung neoplasms, which are other forms:

  • connective tissue tumours and lymphomas (< 0.5%),
  • benign tumours (such as hamartoma) and tumours with low malignancy (such as carcinoids), accounting for less than 5%.

Lung tumors are usually divided into two groups, based on the form of therapy that can be used:

1) Non-small cell carcinoma

Non-small cell lung cancer can be treated by surgery, in combination with radiotherapy and chemotherapy.

Squamous cell carcinoma
Squamous cell carcinoma is also called dandruff cell carcinoma or epidermoid carcinoma. This tumor arises in the large diameter bronchi (upper airways) and represents about 40-50% of cases.
As a rule, it forms in the central lung area and the bronchi can be affected, which can lead to:

  • stenosis (narrowing),
  • atelectasis (collapsed lung section),
  • Necrosis (cell death) caused by the lack of blood supply due to the tumor mass.

This type of tumor is the most common form in men and smokers.

Adenocarcinoma is the second most common form of non-small cell lung cancer, accounting for about 30-50% of cases.
Possible places of origin are:

  • bronchi: bronchial adenocarcinoma,
  • Alveoli: bronchio-alveolar carcinoma. A less aggressive subtype of adenocarcinoma is bronchioloalveolar carcinoma.
    This tumor affects the alveoli.

Adenocarcinoma is observed in non-smokers, especially women.

In contrast to squamous cell carcinoma, it develops more in the external area.
Even if it is of small size, it can be the cause of:

  • metastases to the lymph nodes and distant organs,
  • metastatic pleural effusion.

The diagnosis of this type of cancer may not occur until long after it develops.
The X-ray shows:

  • opacity (white turbidity) as in pneumonia,
  • a fixed knot,
  • scattered nodules.

Large cell carcinoma
Large cell lung cancer is less common and affects only 10% of patients with non-small cell lung cancer.

2) Small cell carcinoma

Small cell lung carcinoma or microcytoma, on the other hand, is less common. It is the most aggressive form of lung cancer and can only be cured with the help of radiation and chemotherapy. The staging of small cell lung cancer is different from the standard.

Causes of lung cancer

There are very significant risk factors.

Esogenic or external risk factors include:

  1. Smoking: the main risk factor. 90% of lung tumours in men and 70% in women are related to smoking.
    The risk depends on the number of cigarettes smoked, how many years you have smoked and at what age you started smoking.
    The risk of cancer decreases by 50% one year after quitting smoking, but does not return to the level of non-smokers.
  2. Passive smoking: represents 20% of lung tumours in people who have never smoked, so it is highly relevant.
  3. Hormone replacement therapy (menopause): a significant risk factor.
  4. Occupational exposures: Asbestos increases the incidence of lung tumours by 5% and the mortality rate is 7%.

Endogenous or internal risk factors:

  • pulmonary fibrosis (especially in women);
  • chronic obstructive pulmonary disease, or COPD for short (in 70-80% of lung cancer cases, this disease precedes it);
  • Lung infections and their scarring.

Lung cancer in non-smokers has the following characteristics:

  • he meets younger people;
  • is more common in women;
  • in most cases, it is adenocarcinoma;
  • has a better prognosis (especially during surgery).

First symptoms of lung cancer

In most cases, there are no early symptoms. When the disease reaches an advanced stage, the symptoms also show up.
Therefore, it is difficult to diagnose lung cancer early.

Symptoms that may indicate lung cancer include:

In the first phase, symptoms occur mainly when the tumor is located inside the lungs.
One of the first symptoms is cough with traces of blood, which manifests itself together with chest pain. The cough can become chronic.

  • Dry and persistent cough that worsens over time. A patient suffering from chronic bronchitis must consult a doctor if the cough occurs more frequently or if the type of sputum changes. Also, a tumor located in the outer area of the lungs can cause coughing if it provokes an ulcer in the mucosa.
  • cough with sputum and blood, also called hemoptysis; it can be caused by: formation of new blood vessels in the tumor, an ulcer in the mucosa, death of tumoral tissue or trauma caused by cough.
  • chest pain, when the mass presses against the pleura and ribs (especially in peripheral tumors). You can also feel a feeling of pressure on your chest, as if there were a stone lying on it.
    Moderate pain in the sternum (sternum) can become more severe and spread to the shoulders, neck and spine.
    Often they aggravate when coughing.
  • Pain in the shoulder and arm, which can reach up to the hand. Pancoast syndrome is caused by tumors that affect the tip of the lung, especially the right one. Such tumors can also affect the first and second ribs, the nerves of the brachial plexus, lower clavicle artery and vein. As a rule, the patient comes to the practice with the healthy arm supporting the affected arm.
  • shortness of breath; it can be caused by: blockage of the trachea or bronchi, large mass in the lungs that occupy a lot of space, pleural effusion, inflammation of the lymph nodes, embolism caused by tumor cells blocking blood vessels.
    One can suffer from shortness of breath, especially in a lying position.
  • Hissing or wheezing sounds when the air passes through a clogged spot in the trachea or bronchi.
  • Fever, because an infection can develop in the area of the lungs where no air can enter.
  • Intractable pneumonia and bronchitis;

Symptoms of advanced lung cancer

The tumor has spread to the organs located in the chest.

Complications from the spread of cancer in the chest

Horner syndrome. If the tumor is located at the tip of the lung and reaches the stellate ganglion (nerve node of the sympathetic nervous system), the following complications may occur:

  • sinking of the eyeball into the eye socket (enophthalmos),
  • pupil narrowing (miosis),
  • perspiration on only one half of the face,
  • drooping of the upper eyelid (ptosis).

Rarely, these phenomena occur all together.

Superior vena cava syndrome. The compression can be caused by:

  • a tumor in the upper right lobe of the lung;
  • a lymph node in the midfur space (near the bronchi), which is affected by the tumor;
  • Formation of a thrombus due to venous stasis.

In 40% of cases, small cell carcinoma is responsible. The symptoms of compression of the vena cava are:

  • swelling of the face, eyelids and neck,
  • headache (due to excessive venous intracranial pressure),
  • Vertigo
  • Fatigue
  • decreased field of vision,
  • Cough
  • dysphagia (dysfunction of the digestive system),
  • dysphonia (voice disorder),
  • cyanosis (blueness).

This problem must be treated with the utmost urgency using internal prostheses to allow blood flow within the blood vessel.

Paralysis of the vocal nerve (recurrent laryngeal nerve): Occurrence in tumor on the upper left lobe or masses on the lymph nodes below the aortic arch that compress or irritate the nerve. The consequences are:

  • difficulty speaking due to paralysis of the vocal cords (dysphonia/hoarse voice),
  • Swallowing disorder (dysphagia) because this nerve innervates the internal muscles of the larynx and the upper part of the esophagus.

Paralysis of the diaphragmatic nerve (phrenic nerve): A tumor in the midfur (center of the chest) can compress the diaphragmatic nerve, which can lead to:

  • hiccups (due to nerve irritation),
  • pain in the shoulder and neck,
  • shortness of breath (when paralysis of the diaphragmatic nerve decreases the movement of the diaphragm on one side).

Heart problems: If tumors or metastases press on the heart, cardiac arrhythmias, fluid accumulation in the pericardium and enlargement of the heart can be the result and lead to heart failure.
Metastases to the heart and pericardium occur in 15% of cases.

Penetration into the esophagus, usually caused by:

  • tumors of the main bronchi or lower left lobe;
  • Lymph nodes of the mediastinum.

The result is swallowing disorders – initially with solid food, later also with liquid food.

Penetration into the trachea or bronchi – a rare case, but it can lead to the formation of a fistula (unnatural tube-like connection) between the bronchi and the esophagus. The result is that the swallowed food enters the lungs. There it can cause aspiration pneumonia.

Symptoms of terminal lung cancer

  • Abnormalities on fingers and nails, such as excessive growth of tissue on the fingertips (drumbeater fingers).
  • Pale or bluish skin.
  • Swelling or joint pain.
  • Bone pain caused by metastases (30-40% of cases).
  • Neurological disorders: drooping eyelids, pupil narrowing.

Diagnosis of lung cancer

The doctor examines the medical history and performs a physical examination in which the lungs and lymph nodes are checked on the sides of the neck and above the collarbone. These are only swollen at an advanced stage, in 20% of cases.

Instrumental procedures
The most important examination for diagnosing lung cancer is chest X-ray.
The X-ray can show:

  • opacity (turbidity) in the lungs,
  • collapsed lung section (atelectasis),
  • Pleural effusion, you can see a large white spot and possibly the deviation of the bronchi.

Laboratory tests

  • Blood tests.
  • Search for tumor markers. Their presence or increase in certain forms of neoplasms does not allow diagnosis, but they are helpful in monitoring the disease. The most important tumor markers are: CEA (carcinoembryonic antigen), especially in adenocarcinoma, NSE (neuron-specific enolase) and chromogranin for small cell lung cancer and neuroendocrine tumors and CYFRA 21 for squamous cell carcinoma.
  • Cell and tissue analysis of the expectorate (secretions). Sampling of three different days is required. With peripheral tumor, a false negative result may occur. This analysis is very helpful in squamous cell carcinoma, which causes increased scaling.

Biopsy means the removal and examination of a small amount of tumor tissue.
With the biopsy, the pathologist analyzes the removed tissue to determine the type of tumor.

The biopsy may be performed during other invasive examinations, such as:

  • Video bronchoscopy. A bronchoscope (with video camera) is inserted and advanced through the airways into the bronchi. During this examination, tissue samples may be taken.
  • Transthoracic needle biopsy with radiological control. Local anesthesia is necessary for this examination. With the help of computed tomography, the doctor inserts a needle into the lungs and takes a tissue sample.
  • Pleural puncture. Pleural fluid is removed through the thorax. In pleural effusion, cell analysis of the fluid can reveal the presence of tumoral cells. This means that the tumor is at an advanced stage. When he reaches the pleura, he is inoperable. Especially adenocarcinoma leads to the appearance of tumor cells in the pleural effusion. In any case, in more than half of cases, this examination may not be helpful for diagnosis.
  • Thoracoscopic surgical biopsy. This examination is performed under general anesthesia. The surgeon makes three small incisions and inserts a thoracoscope, which can be used to examine the lungs and pleural cavity. The surgeon removes tissue that is analyzed. This procedure is more invasive and a hospital stay is required.

Imaging examination methods

The patient may also undergo other examinations to determine the spread of the tumor:

  • computed tomography (CT),
  • magnetic resonance imaging (MRI),
  • Positron emission tomography (PET).

Determination of stages in lung cancer

Staging in lung cancer is an important field of study because it helps clinicians determine how far the tumor has grown. Depending on the stage of development and severity, the doctor determines:

  • a prognosis of the carcinoma,
  • therapy.

Determination of the stages of the small cell tumor
The small cell tumor can be divided into 2 stages:

  1. limited disease: the tumor is localized only in the lungs;
  2. spread disease: the tumor has formed distant metastases.

Determination of the stages of the non-small cell tumor
The staging determination of the non-small cell tumor follows the standard determination.

Stage I
The tumor tissue is in the initial state:

  • less than 3 cm in diameter,
  • has not yet spread.

Therefore, it can be easily removed by surgery.

Stage II
At this stage, the tumor slowly spreads to the adjacent areas.

This stage is divided into: Stage 2A:

  • The tumor measures 3-4 cm.
  • The adjacent lymph nodes are not affected.

Stage 2B:

  • The tumor measures 4-7 cm.
  • Adjacent lymph nodes are affected.
  • The tumor may have spread to:
    • Diaphragm;
    • lung wall;
    • thoracic wall;
    • external heart wall (pericardium).

Survival rate for stage 1-2
lung cancer 
The 5-year survival rate is 65-80%.

Stage III
At this stage, the tumor continues to develop and can spread to the blood vessels that connect the lungs to the heart. This phase is extremely dangerous and irreversible.

The 3rd stage is divided into two subspecies.

  • In the first phase, called 3A:
    • the tumor has a diameter of 3-7 cm;
    • the adjacent lymph nodes located in the chest are affected;
    • the tumor has spread to the chest wall, diaphragm and pericardium.
  • In the second phase, called 3B:
    • the tumor spreads aggressively, it also attacks the heart, trachea and esophagus;
    • the lymph nodes of the entire chest are affected.

Therapy for lung cancer in stage 3

In most patients, a phase 3B tumor is difficult to remove surgically and treatment is limited to radiation therapy and chemotherapy.

Survival rate for stage 3
lung cancer 
The survival rate for stage 3 lung cancer depends on the therapy and the general health of the patient. However, the average survival rate is between 7 and 17%.
The prognosis for lung cancer is generally very poor due to the lifestyle of most patients after diagnosis.

Only 5-10% of patients with stage 3B lung cancer survive longer than 5 years.
Patients undergoing chemotherapy have a longer life expectancy if they lead a healthy lifestyle.
The prognosis for lung cancer is better for patients undergoing chemotherapy, with a five-year survival rate of 15-20%. However, these statistics are not very meaningful because they do not take into account:

  • genetic aspects,
  • the lifestyle of patients.

Stage four lung cancer

This is the most serious stage, as treatment is no longer possible here. The cancer has spread to other parts of the body and you can only:

  • limit the damage,
  • relieve the symptoms.

The terminal stage, or lung cancer in stage four, is an irreversible disease in which the cancer cells have spread to healthy organs of the body (distant metastases).

Symptoms of stage 4 lung cancer depend on the localization of the primary tumor and metastases.
The staging is based on the spread of the tumor to the body organs.

After conducting all the necessary diagnostic examinations, the doctor determines therapy and the prognosis of the lung tumor at the fourth stage.
In the final phase, the cancer has spread from the chest area to other organs of the body (lung metastases).

Symptomatic treatment from the time of diagnosis is important to treat the cancer.

Therapy for lung cancer in stage
Chemotherapy or radiotherapy is given to destroy cancer cells and slow down the progression of the disease.
Surgical removal of the diseased area is not possible in the fourth stage, as this is not effective.

How long do you live? Prognosis and life expectancy

The survival rate depends on the physical condition of the patient and the treatment performed.
In most cases, the third stage of lung cancer leads to phase 4, which is fatal.

For prognosis and life expectancy, different factors must be taken into account:

  • Age
  • Sex
  • individual state of health,
  • spread of the tumor,
  • Reaction of the patient to the administered therapy, etc.

These factors play a fundamental role in end-stage forecasting.

The tumors with the better prognosis and therefore higher survival rate are detected in patients who:

  • have no symptoms,
  • whose symptoms are related only to the primary tumor.

The outlook worsens in patients with systemic symptoms, such as:

  • loss of appetite (anorexia, 35%),
  • weight loss (40-50%),
  • weakness (asthenia, 30%),
  • symptoms caused by metastases.

As a rule, patients who do not have objective, clinical or laboratory-proven changes are less likely to metastasize:

  • in the brain,
  • in the bones,
  • in the abdomen.

The survival rate is very low in the fourth stage.
Only 5-10% of people affected by lung cancer survive up to 5 years.
In non-small cell carcinoma, only 10-15% of patients survive up to 5 years.
Compared to other types of cancer, the prognosis for stage 4 lung cancer is considerably worse.

Late diagnosis is one of the main factors in the low survival rate in patients affected by lung cancer.

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