Causes and risk factors
Several factors have been identified as responsible for its occurrence. The most important one is cigarette smoking, which is the main cause of about 90% of lung cancer cases.
Which are the symptoms?
Patients with early-stage cancer may not have any complaints. The detection of a tumor in these cases sometimes occurs after a chest x-ray has been taken for other reasons. Patients with more advanced tumors may experience: cough, shortness of breath (dyspnea), chest pain, and/or bleeding when coughing (hemoptysis or bloody expectoration). If left untreated, lung cancer can gradually affect adjacent anatomical structures (chest wall, heart and large cardiac vessels, trachea, vertebrae) and/or spread distantly (metastases). The most common sites of metastasis are the lymph nodes in the mediastinum (the space between the two lungs), the lung opposite to the focus of the disease, bones, brain, liver and adrenal glands.
- chest pain
- bleeding when coughing (hemoptysis or bloody expectoration)
How is it diagnosed?
Diagnosis is the process of determining the presence of a disease, that is, in this particular context, lung cancer. On the other hand, staging is the process of establishing the spread of the disease (i.e. whether the tumor is localized in the lung or has already affected other organs). Staging is a critical process because localized lung cancer or, conversely, cancer with distant metastases requires completely different types of treatment.
At the first visit to a specialist, a doctor (thoracic surgeon, pulmonologist or oncologist) will assess the disease and prescribe the necessary tests for diagnosis and staging.
The instrumental examinations used for the diagnosis and staging of lung cancer are as follows: chest x-ray, chest CT scan, bronchoscopy with bronchoscopy and biopsy, whole-body PET scan, abdominal CT scan, brain CT scan, bone scintigraphy, CT-guided needle aspiration, transbronchial aspiration (needle biopsy).
In some cases, mediastinoscopy and thoracoscopy may be required to accurately determine the spread of the disease.
The use of these instrumental examinations and interventions makes it possible to identify four different stages of the disease. While stage I includes small tumors without metastases, other stages include larger tumors and/or tumors with distant metastases. The severity of lung cancer appears to increase from stage I to stage IV.
The choice of the type of instrumental examination for a particular patient and the sequence of studies are determined by a specialist and may vary from case to case. However, it is important to achieve, with reasonable confidence, using all available examinations, accurate diagnosis and staging in order to be able to treat the patient appropriately.
Transbronchial needle aspiration (needle biopsy)
This is a procedure performed during a bronchoscopy in which tissue from the lung or lymph node is taken to determine the nature and presence or absence of lymph node metastases. It is usually performed under deep sedation. Complications are exceptional and the patient may return to normal activities one hour after the examination. The most obvious advantage of this examination is that more invasive diagnostic procedures such as mediastinoscopy or videothoracoscopy can be avoided.
Mediastinoscopy is a surgical procedure, although minor, performed under general anesthesia. Samples are taken from the mediastinal lymph nodes through a small incision in the lower part of the neck using a special instrument called a mediastinoscope. Complications are very rare. This procedure is necessary to check for lymph node metastases in lung cancer or to diagnose other types of lymph node disease (such as sarcoidosis). However, in many patients, mediastinoscopy can be avoided by performing bronchoscopic transbronchial needle aspiration first.
This is an invasive technique commonly used for a variety of lung, mediastinal and pleural surgeries. It is also used in the staging of lung cancer because it allows the examination of the pleural cavity and biopsies, in particular of the parietal pleura and mediastinal lymph nodes.
How is it treated?
Treatment depends on the type of tumor (non-small cell or small cell), the degree of spread of the tumor (early or advanced stage), as well as the general condition of the patient and the state of his respiratory system. Treatment includes surgery and/or various forms of systemic cancer therapy (chemotherapy, radiotherapy, biological therapy, immunotherapy).
Surgery is mainly effective in the early stages, its goal is the physical removal of tissue from the body, resection of the mass at its root.
Thanks to the use of robotic thoracic surgery, it has been possible for several years to perform more precise and minimally invasive surgery on early stages of tumors, as well as on locally advanced lung tumors up to stage III, with less trauma and a better quality of life for the patient. Surgeries used to treat lung cancer include atypical resection, segmentectomy, lobectomy, and pneumonectomy. Many of these surgeries can now be performed using minimally invasive techniques. The choice of a specific type of operation is carried out by the surgeon depending on the size and location of the tumor and the state of the patient’s respiratory system.
Chemotherapy (i.e. antineoplastic chemotherapy) is generally recommended in the advanced stages because it is aimed at destroying tumor cells and blocking their spread. In practice, the use of different drugs containing different cytotoxic therapeutic agents uses different mechanisms of action on cancer cells.
Research on more modern or alternative therapies for lung cancer is advancing, but is encountering natural limitations, and the pace is slow.
Radiation therapy involves the use of rays to target the tumor and destroy it. Currently, there are high-tech radiotherapy systems such as tomotherapy and cyberknife, which only act on the tumor area without affecting the surrounding healthy tissue. Depending on the histological type and stage of the disease, radiotherapy possibly associated with chemotherapy can represent an important therapeutic option for patients with lung cancer. Radiant treatment can be used after surgery to reduce the risk of local recurrence or before surgery to achieve a reduction in the extent of the disease. Radiation therapy can also be used as an exclusive curative treatment in cases of surgically non-treatable disease or in patients with contraindications to surgery.
IMMUNOTHERAPY OR MOLECULAR-DIRECTED THERAPY
Two new treatment options are currently available: immunotherapy and so-called “molecular targeted therapy”. The first works by improving the immune system to limit the growth of tumor cells. The latter is the result of genomic studies that have shown that certain types of cancer are caused by specific damaged genes; therefore, specific drugs have a direct effect on the restoration of disrupted genetic circuits.
It is now well known that referring to a common form of cancer is incorrect. There is no single tumor, but there are several forms that are very different from each other. The tumor results from a mutation in the DNA of the cells, particularly in certain combinations of genes, which can vary greatly from patient to patient. The effectiveness of therapy varies from person to person. The effectiveness of therapy varies from person to person.
Most non-small cell lung cancers can only be treated with surgery, while more advanced cancers require combination treatment. In contrast, small cell lung cancer is usually treated with chemotherapy alone, in various combinations with radiotherapy, and surgery is infrequent.
The results of treatment of non-small cell lung cancer are good in stage I of the disease, when it is possible to cure a small tumor without distant metastases. In these cases, the 5-year survival rate is over 70%. However, especially when combined treatment regimens are used, long-term survival is also possible in the later stages of the disease.