Lung squamous cell carcinoma is a type of lung cancer that is particularly strongly associated with exposure to tobacco smoke, so it occurs most often in smokers, but also in people exposed to tobacco smoke. It is worth finding out what its symptoms, treatment methods and prognosis are.
Lung squamous cell carcinomaaccounts for approximately 30% of all tumors in this organ. This cancer belongs to the group of lung cancers, but its starting point is the altered cells of the lower respiratory tract - the bronchi.
Lung squamous cell carcinoma belongs to the group of non-small cell carcinomas, which constitute the majority of lung cancer cases (over 80%), the remaining types of lung cancer are small cell carcinomas, metastases from other organs, and other rare tumors, e.g. sarcomas.
Small cell lung cancer is a cancer whose occurrence is particularly strongly related to smoking, and quitting smoking significantly reduces the risk of developing the disease.
Lung cancer is the leading cause of death among neoplastic diseases and, in accordance with the observed trends, this state of affairs will continue for many years, moreover, the fact that the number of women suffering from this cancer is increasing is a disturbing phenomenon.
The dangers of lung cancer are the lack of early symptoms and the lack of effective screening tests available.
Regardless of the stage of advancement, treatment of this neoplasm is undertaken, but depending on the stage of advancement, the goals of the therapy vary.
If it is possible, the aim is to cure, if the process is very advanced, only palliative treatment can be understood, because at an advanced stage, the effectiveness of the methods of treatment known to us is low.
The hope for improving the results of lung cancer treatment lies in molecularly targeted drugs, which are currently intensively researched and slowly introduced into therapy, perhaps they will become the treatment of choice in the future and will allow for an effective fight against this disease.
Squamous cell carcinoma of the lung: symptoms
Unfortunately, early-stage lung cancer usually causes no symptoms, and there are no highly effective, readily available screening methods for this type of cancer. That is why it is so important to avoid exposure to the factors causing the development of this disease - above allquitting smoking.
If symptoms already appear, the most common is a dry cough, and in smokers its nature changes - it becomes more intense or appears at other times of the day. In addition, it may be accompanied by dyspnoea, chest pain, and in advanced forms - hemoptysis.
Recurrent pneumonia is a less common symptom, especially if it occurs in the same area of the organ. They are caused by damage to the defense mechanisms of the organism by the ongoing process of proliferation - the immune system is impaired and the mechanisms that purify the respiratory tract, which favors the multiplication of bacteria.
Other symptoms of lung cancer are rare and usually in advanced cases, these unusual symptoms are:
- the so-called superior vena cava syndrome, manifested by swelling, redness of the face and neck, conjunctival redness and swelling of the hands. Headaches and dizziness are less frequent
- shoulder pain
- Horner's syndrome caused by damage to the nerve fibers that run to the eyes
- arrhythmias if the infiltrate affects the heart
- hoarseness as a result of laryngeal nerve palsy
- pleural fluid
- atelectasis, i.e. a reduction in the aeration of the parenchyma
If any of the above-mentioned symptoms occurs, and there are no symptoms suggesting a respiratory disease, diagnosis begins with looking for other causes, because the probability of this neoplasm is low.
It is most common for the aforementioned ailments to appear in the advanced stage, when other symptoms have already led to the diagnosis.
If squamous cell lung cancer is at an advanced stage, there are also: weight loss, weakness, these are late symptoms, as well as those caused by metastases, for example:
- bone pain and so-called pathological fractures that occur with bone metastases
- headaches, seizures, balance disorders and behavioral changes as a result of metastases to the central nervous system
- epigastric pain, nausea, jaundice, if metastases appear in the liver
In the course of squamous cell neoplasm, so-called paraneoplastic syndromes caused by the secretion by the tumor of hormones or substances similar to them, which affect the metabolism of the system, may appear extremely rarely. These include, for example :
- Cushing's syndrome
- carcinoid syndrome
- excess calcium
- neuropathies
- skin changes
- venous thrombosis
- anemia
Cancersquamous cell lung: risk factors
As mentioned in the introduction, the most important risk factor for squamous cell carcinoma of the lung is smoking, it depends on the period of smoking, intensity and age of addiction, increasing the probability of the disease up to several dozen times.
Tobacco smoke contains many substances with proven carcinogenic effects, and the nicotine content does not affect the likelihood of getting sick, and there is no "safe" amount or duration of smoking.
People who quit smoking have a lower risk of getting sick, but are still higher after many years without smoking than those who have never smoked.
Passive smoking is also dangerous, it is estimated that even half of people who did not smoke actively and developed squamous cell carcinoma were exposed to tobacco smoke.
The impact of so-called e-cigarettes on lung cancer is currently unknown - they are too briefly available to draw conclusions about their he alth effects.
Other risk factors for lung cancer are much less important, including: genetic predisposition, exposure to ionizing radiation (radiotherapy), exposure to asbestos and heavy metals.
Squamous cell carcinoma of the lung: diagnosis
Lung cancer-like symptoms can cause:
- benign tumors
- lung abscess
- tuberculosis
- sarcoidosis
- but also tumor metastases from other organs
In order to make a reliable diagnosis, it is necessary to perform some additional tests.
If there is a justified suspicion of lung cancer, an extended diagnosis is necessary in order to detect or exclude this cancer. It begins with a chest X-ray in two projections, i.e. anterior and lateral, it may show the tumor itself or indirect features that may indicate it, e.g.
- lymph nodes enlargement
- pleural fluid
- nieododmę
- sometimes bone metastases
When disturbing changes appear on the x-ray, each GP should refer the patient to a specialist.
Although sometimes the lesion is invisible in the photo, then, if the symptoms persist, the specialist will order further tests, e.g. computed tomography, bronchoscopy, which allows for direct visual examination of the larynx, trachea and bronchi, or thoracoscopy, that allows you to view the lung and the entire pleural cavity.
During this research, you can fromimmediately take tissue samples for histopathological examinations, which will decide whether the lesions are malignant or not. Cancer takes a long time to develop and can be won when the fight is started early.
Unfortunately, a correct X-ray image does not exclude the occurrence of neoplasm with 100% certainty.
Another useful test is a chest CT scan.
The so-called low-dose tomography is useful in the diagnosis of cancer suspicion, while the "standard" computed tomography is primarily used to assess the advancement of the disease: tumor size, infiltration of adjacent structures and the presence of metastases in the lymph nodes.
PET plays a similar role, it allows to detect small metastases in the lymph nodes and possible metastases outside the chest, moreover, this examination is necessary when planning treatment - both in the scope of surgery and radiotherapy.
Magnetic resonance imaging is used less frequently in diagnostics.
The next stage of diagnostics, after imaging examinations, is obtaining material for cytological and cellular examination.
In the case of small cell lung cancer, it is most often located around the lung cavity, the place where the bronchus enters the lungs. This location makes it easier to obtain the cellular material by means of bronchoscopy, i.e. bronchoscopy performed through the nose or mouth, this examination allows to assess the extent of the tumor, collect specimens for examination, or perform endobronchial ultrasound examination of lymph nodes.
If this method of specimen collection is ineffective, a tumor biopsy is performed via transesophageal examination.
Other methods are: sputum examination (rarely effective), mediastinoscopy, i.e. mediastinoscopy, and thoracotomy, i.e. collecting the material after opening the chest.
Before starting treatment, tumor cells must be harvested and microscopically assessed, as further treatment depends on it.
The determination of tumor markers in the blood has no clinical significance at the stage of diagnosis.
In recent years, molecular diagnostics has become more and more important, giving the possibility of individual treatment selection depending on the mutation profile of a given patient's cancer. It involves the assessment of the DNA of the tumor cells, it is performed as a next step after the cytological examination, if certain mutations are found, it is possible to use drugs that block signal pathways damaged by these abnormal genes.
Lung squamous cell carcinoma: staging
There are 4 basic levels of advancementlung cancer:
I ° - neoplasm limited to the lung parenchyma
II ° - neoplasm confined to the lung parenchyma with lymph node metastases
III ° - neoplasm infiltrating the structures of the mediastinum, the spine or metastasizing to lymph nodes
IV ° - spread to distant organs
The staging is assessed on the basis of the aforementioned imaging examinations, especially the chest computed tomography with contrast.
In addition, brain resonance or tomography and bone scintigraphy are useful in order to exclude the presence of metastases in patients with suspected metastases in these organs. Lymph nodes are assessed on the basis of a PET examination or biopsy.
Squamous cell carcinoma of the lung: treatment
It has been proven that this type of neoplasm is not very susceptible to chemotherapy, and the decision as to the treatment method is made by a medical consultation after assessing the severity of the disease and the general condition of the patient.
In the early stages, the method of choice is surgery involving the removal of the lobe, very rarely the entire lung, and regional lymph nodes.
In more advanced cases, surgery preceded by chemotherapy may be used. Another method of therapy is the so-called combination treatment, it is a combination of two techniques from among:
- operation
- radiotherapy
- chemotherapy
Most often used:
- preoperative radiotherapy, sometimes including chemotherapy,
- postoperative radiotherapy, if there is no certainty that the tumor will be removed during the procedure
- preoperative chemotherapy to reduce the severity of the disease and increase the chance of complete tumor removal
- postoperative chemotherapy
Another important method of treating small cell lung cancer is radiotherapy, it is used in people who cannot undergo surgery due to the advancement of the cancer or the presence of contraindications to the procedure. Types of radiation therapy:
- radical - if the tumor is limited, no metastases occur, the goal is to cure
- stereotaxic - in the earliest stages of the cancer, if surgery is contraindicated
- palliative - aimed at reducing symptoms in the most advanced stages of the disease
Endobronchial treatment is rarely used, it consists in: delivering radioactive material - brachytherapy, i.e. direct irradiation of lesions, phototherapy or widening of the airways - stenting.
It is only exceptionally used in squamous cell lung cancerchemotherapy, most often in the treatment of advanced disease, to reduce symptoms.
Recently, we also have targeted therapy, molecularly targeted at those changes in cell metabolism that are responsible for the development of cancer.
In squamous cell lung cancer, so-called human epidermal growth factor receptor tyrosine kinase inhibitors - erlotinib, gefitinib, afatinib, osimertinib, as well as monoclonal antibodies: atezolizumab, nivolumab are used.
Lung squamous cell carcinoma: disease advancement and treatment options
On the basis of specialized studies, the advancement of the neoplasm is determined in more detail by dividing the grades into subsequent categories or using the detailed TNM classification. The assessment of disease progression is the basis for planning its therapy and selecting the appropriate treatment.
Surgical treatment with the intention to remove the entire mass of the tumor is performed at stages 1 and 2, sometimes with chemotherapy.
In the less advanced stages of Grade 3, treatment begins with chemotherapy followed by surgery. Advanced grades 3 and 4 are the most severe forms of the disease, in such cases treatment with radiotherapy or radiotherapy and chemotherapy is performed.
Squamous cell carcinoma of the lung: prognosis
The prognosis depends largely on the primary stage of the disease (size, location, infiltration, presence of metastases in nodes and other organs), as well as age, gender, and molecular features of the tumor.
It is believed that in stages 1 and 2 it is possible to heal more than 50% of patients, while in stages 3 and 4 only less than 15%. The appearance of distant metastases worsens the prognosis, but of course it does not rule out further treatment (most often it is chemotherapy).
Unfortunately, the prognosis for lung cancer is very poor, mainly due to late cancer detection, which in turn is due to the lack of early symptoms and effective screening tests.
It is estimated that only about 10% of patients with squamous cell carcinoma can be cured, and less than 20% of patients undergo effective surgery.
Due to such a bad prognosis, it is necessary to reduce the risk factors, first of all, to stop smoking.