The lungs are paired cone-shaped organs situated in the thoracic cavity. They are covered with the double-layered pleural membranes (membrane directly covering the lung is called visceral pleura and the external one is called parietal pleura) that secrete and enclose a lubricating fluid within the space between them (the pleural cavity). The right lung has 3 lobes and is slightly bigger than the left lung, that has 2 lobes.
When air is inhaled, it travels from the nostrils into the lungs via trachea (windpipe) and its two branches called bronchi. Inside the lungs, bronchi further divide into small lobular bronchi and keep on dividing inside the lobes to form a network of microscopic branches called bronchioles. At the end of each bronchiole are small grape-like air-sacs called alveoli that act as a site of gases exchange during respiration. The main function of the lungs is to bring about this gases exchange, that is, intake of oxygen and removal of carbon dioxide.
Epidemiology of Lung Cancer in Delhi
Lung cancer is one of the leading causes of cancer across the world. But in Delhi, it is on the rise. With the increasing air pollution, incidence of lung cancer is rising even for non-smokers in Delhi. 30 years back, smokers accounted for almost 90% of cases of lung cancer.
But in the current scenario, it is almost equally divided between smokers and non-smokers. And in the younger age group, less than 50 years, around 70% of lung cancer cases are non-smokers. The average age of lung cancer is also falling in Delhi. 20 years back, it was 50-60 years, but currently it has come down to 30-40 years. Also, the incidence is on the rise in females, with 40% of cases being women.
Types of Lung Cancer
Broadly, lung cancer is mainly divided into 2 types:
- Non-small cell lung cancer (NSCLC) that constitutes about 80% to 85% of all lung cancers and
- Small cell lung cancer (SCLC).
Histologically, lung cancer can be of several types such as squamous cell carcinoma, adenocarcinoma, large cell carcinoma, neuroendocrine tumors, large cell neuroendocrine carcinoma, small cell carcinoma, and lung carcinoid tumors among others. Adenocarcinoma, squamous cell carcinoma, and large cell carcinoma are grouped together as NSCLC. SCLC, also known as oat-cell carcinoma is a type of neuroendocrine tumors, which tend to grow and spread very rapidly.
Risk Factors for Lung Cancer
The strongest determinant of lung cancer in smokers is duration of smoking. Risk also increases with the number of cigarettes smoked. Cessation of smoking for 10 years reduces risk but never to control levels. However, the risk of ex-smokers for lung cancer remains elevated for years after cessation, compared to the risk of never smokers.
Smoking increases the risk of all histologic types of lung cancer: squamous , small cell, adeno (including bronchiolar-alveolar), and large cell carcinoma. It causes lung cancer in both men and women. Adenocarcinoma has replaced squamous cell carcinoma as the most common type of lung cancer caused by smoking in the United States and elsewhere.
Occupational/ Environmental exposure
Exposure to Radon (a radioactive gas produced from the decay of Radium or Uranium) has been reported to increase the risk of developing lung cancer.
Occupational exposure to Asbestos has been reported to increase the incidence of lung cancer in workers in mines, textile and other mills, and shipyards.
Similarly, higher incidence of lung cancer has been observed in people with occupational/environmental exposure to chemicals like arsenic, beryllium, cadmium, silica, chloromethyl ethers, hexavalent chromium, mustard gas, nickel, coal products, and polycyclic aromatic hydrocarbons.
People living in an area with a high level of air pollution are considered to be at an increased risk of developing lung cancer.
Gender and Ethnicity
Women smokers are more likely than men to develop adenocarcinoma of the lung, and women who have never smoked are more likely to develop lung cancer than men who have never smoked. Furthermore, the 5-year survival rate for women who have lung cancer is 15.6%, while it is 12.4% for men. Women survive longer after surgical resection of early-stage lung cancer as well as after treatment of metastatic disease; female sex has been associated with longer survival in SCLC as well.
Hormonal, genetic, and metabolic differences between the sexes are believed to account for these clinical differences. Indeed, estrogens were found to be involved in lung carcinogenesis, either by acting as estrogen receptor ligands and activating cellular proliferation pathways, or by metabolic activation to reactive intermediates that can produce DNA adducts and cause oxidative damage.
The lung cancer incidence rates vary by nearly five fold in men and over 10-fold in women across the WHO regions, reflecting differences in historical patterns of smoking. The highest rates are among men in Eastern Europe, Southern Europe, and North America, whereas the lowest rates are observed in Central America and South Central Asia.
Lung cancer incidence and death rates among men have begun to fall in North America, Northern Europe, Australia, and New Zealand but continue to rise in many other countries.
Lung cancer patterns in women differ from those in men because the uptake of widespread cigarette smoking among women lagged behind that in men by approximately 25 years, even in industrialized countries.
The prevalence of cigarette smoking is still low among women in much of Asia and Africa, but in Europe and parts of South America, teenage girls are now smoking more than teenage boys.
The highest lung cancer rates among women are currently in North America, Northern Europe (especially Scandinavia), and Australia and New Zealand.
Factors other than cigarette smoking contribute to the relatively high background rate of lung cancer among women in parts of China.
The lung cancer incidence rate per 100,000 for 2008 among Chinese women (21.3/100,000) is higher than that among women in Germany (16.4) and France (14.7), despite their lower prevalence of smoking.
Factors thought to contribute to the high lung cancer rate among Chinese women in certain regions of China include
- indoor exposure to coal smoke
- indoor emissions from burning other fuels
- exposure to fumes from frying foods at high temperatures
- secondhand smoke.
Personal or Family history
Risk of developing lung cancer increases in individuals with a personal or family history of lung cancer, especially in first-degree relatives (parents, brother, sister, or child) diagnosed with the disease at a younger age.
Some inherited genetic alterations have been reported to be associated with a high incidence of lung cancer. Individuals with inherited mutations in following genes have been reported to be at higher risk of developing lung cancer: retinoblastoma, p53 (Li-Fraumeni syndrome), gene for epidermal growth factor receptor (EGFR), etc.
Individuals with germ line mutations affecting expression of genes regulating cell cycle progression or response to DNA damage appear to have increased lung cancer risk. A threefold increase in lung cancer risk has been observed in patients with Li-Fraumeni syndrome who smoke relative to smokers without p53 germ line mutations.
Interestingly lung cancer susceptibility is influenced by genetic variation in a gene encoding for a nicotine receptor. The association of this genetic variant with lung cancer may actually be mediated through its effect on smoking behavior. Individuals with this variant generally smoked more cigarettes per day and showed more nicotine dependence than people without the variant.
This finding suggests that the gene variant actually influences an individual’s exposure to an environmental agent (tobacco smoke), and it is this higher exposure that is then responsible for the individual’s increased risk of cancer.
Exposure to radiation
Individuals with a history of radiation treatment (for other cancer) or exposure to ionizing radiation to the chest (for example, during an x-ray or computed tomography scan) are considered to be at increased risk of developing lung cancer, especially if they smoke.
The presence of underlying pulmonary conditions like chronic obstructive pulmonary disease (COPD) or idiopathic pulmonary fibrosis may also increase the risk of lung cancer.
Lung Cancer Symptoms and Signs
Final stages of lung cancer means when the can has spread to distant sites or organs. The symptoms of final stage lung cancer may be local symptoms due to lung mass or symptoms of distant spread, depending on the site or organ of spread.
Symptoms of Local Spread
Chronic cough that does not respond to treatment and gets worse with time may be a sign of lung cancer. It may be dry cough or associated with sputum production, due to underlying infections. Sometimes, it may contain blood.
Pain in the chest
Pain in the chest that gets worse while coughing may be due to lung cancer. A superficial lung mass may involve the parietal pleura covering around the lung, which is pain sensitive.
Irritation or rubbing of the parietal pleura by lung mass, like on deep inspiration or coughing may cause chest pain or discomfort.
Blood in sputum
Blood in sputum or phlegm may be another indicator of lung cancer. It may be blood tinged or grossly red in colour, depending on the amount of blood in sputum.
This usually happens when the lung mass erodes into the airway, and is more common with centrally located lung cancer compared to peripheral ones.
Hoarseness of voice
Sometimes, lung mass may irritate or involve the recurrent laryngeal nerve. This nerve mainly passes through the thoracic cavity and supplies the larynx or voice box. Hoarseness of voice may result from it’s involvement by tumor.
Shortness of breath or difficulty in breathing
A large lung mass that involves a large part of lung may limit it’s capacity to expand effectively. This may cause breathlessness, especially on exertion or activity.
Sometimes, there may be fluid collection in the pleural cavity surrounding the lung (pleura effusion). This may also restrict the expansion leading to this symptom.
Persistent or Recurrent Infections
Persistent infections like bronchitis or pneumonia that do not respond to treatment may be due to lung mass obstruction the airway and causing the lung secretions to stagnate. This may cause superadded bacterial or viral infections that may be difficult to get rid off at times.
Symptoms of lung cancer may also depend upon the size and location of the disease. Large tumors may produce symptoms due to compression of adjacent structures, for example, compression of the esophagus may cause difficulty in swallowing and compression of the superior vena cava may cause facial edema.
Symptoms of Distant Spread
Approximately 30% to 40% of NSCLC and 60% of SCLC patients present with metastatic disease. The most common sites of hematogenous spread are CNS, liver, bones and adrenal glands. Diffuse meningeal involvement is uncommon at the time of initial presentation, but it may be seen later in the course of the disease, particularly with SCLC. The lymphatic spread of lung cancer may manifest with cough and dyspnea, depending on the extent of parenchymal involvement
- Bone pain or fractures – if lung cancer has metastasized to bones.
- Jaundice, Fatigue, Nausea, or bloating – if lung cancer has metastasized to the liver.
- Vision issues, severe headaches, or seizures – if lung cancer has metastasized to the brain.
- Cough, breathlessness, and chest pain.
- Loss of appetite.
Lung metastasis are more commonly multiple than single, and bilateral than unilateral.
Some cases are associated with a group of specific symptoms (or syndromes) like Horner syndrome, superior vena cava syndrome, or paraneoplastic syndrome.
What are the Investigations for Lung Cancer Diagnosis?
If an individual is suspected to have lung cancer based on signs and symptoms, detailed investigations are required to establish the diagnosis and stage the disease, which in turn helps in selecting an appropriate treatment option.
In this test, a sputum sample is collected and examined under a microscope for the presence of cancer cells. This test can help in the diagnosis of cancer in the major airway of the lung like squamous cell carcinoma and small cell carcinoma. The test is recommended to be performed on at least 3 sputum samples collected on 3 successive days. The test is safe and can help in early diagnosis of the disease.
Bronchoscopy is a diagnostic technique which uses a bronchoscope – a long, flexible, slender tube usually equipped with a camera, a light source, and some special instruments for biopsy or surgery.
The bronchoscope is passed through the nose or mouth into the trachea and bronchi. A real-time image of the interior of the airways is produced on a computer screen by the bronchoscope. This enables the doctors to directly observe the lining of the trachea and bronchi to determine the abnormalities. Biopsy samples are generally collected from abnormal areas during the examination.
Fluorescent light can also be used with bronchoscopy (fluorescence bronchoscopy), which can help in the detection of some early-stage cancerous changes (pre-cancerous lesions) in the airway. This technique can also be utilized for delivering certain treatments for early-stage disease (for example, photodynamic therapy) or palliative treatments for advanced stage disease (for example, stent placement).
Endobronchial Ultrasound (EBUS)
In this technique, an ultrasound device (transducer) is used along with an endoscope – a long, flexible, slender tube usually equipped with a camera, a light source, and some special instruments for biopsy or surgery. The endoscope is passed through the nose or mouth into the trachea and bronchi.
This test helps the doctor to closely examine the lymph nodes and other structures in the space between the lungs (mediastinum) for any abnormality. This test can sometimes be used to guide a biopsy needle to take biopsy samples from the affected areas/enlarged lymph nodes observed during the test.
Endoscopic (Esophageal) Ultrasound (EUS)
This technique is very much similar to EBUS except that the endoscope is passed into the esophagus instead of the bronchi. Sometimes, it may be useful to approach those areas that are not possible with EBUS.
In this technique, an instrument similar to an endoscope is inserted into the space between the lungs and the chest wall through an incision made on the side of the chest wall. This test helps in the diagnosis of cancer on the outer surface of the lungs and the pleural membranes.
Biopsy samples can be collected from these areas and from affected lymph nodes diagnosed during the procedure. This can be used as a part of surgical treatment for early-stage lung cancers and the procedure is known as video-assisted thoracic surgery (VATS).
Mediastinoscopy and Mediastinotomy
These techniques are used to collect tissue samples from the lymph nodes along the trachea and bronchi in the mediastinum. In mediastinoscopy, an instrument similar to an endoscope is inserted into the space between the lungs via a cut in front of the neck. Mediastinotomy is more extensive than mediastinoscopy and provides access to more lymph nodes.
One or more of the following tests are required to stage the disease and assess response to treatment-
Computed Tomography (CT) Scan
In this technique, detailed cross-sectional images of body organs are generated using x-rays, with or without a contrast medium. It can help diagnose the spread of disease to nearby/distant lymph nodes and other organs, and may also be used to guide a biopsy needle into the affected area.
Positron Emission Tomography (PET) Scan
This technique uses a radioactive substance (fluorodeoxyglucose [FDG], etc) that is given via intravenous injection prior to the procedure. Cancer cells absorb larger amounts of the radioactive substance than normal cells. The areas of higher radioactivity indicate cancerous tissue on the PET scan. Thus, this technique can diagnose unsuspected spread of disease to distant body parts. It is usually combined with a CT scan (PET/CT).
Magnetic resonance imaging (MRI) scan
This technique provides detailed images of tissues inside the body using radio waves, a strong magnetic field, and gadolinium contrast. It can accurately diagnose the extent of invasion and spread of disease to nearby/distant body parts.
In this test, a radioactive material is injected into the vein of the patient, which gets accumulated in the areas of bones affected by the disease, which are then detected with the help of radioactivity detectors. In this way, it may help to detect the spread of cancer to bones.
It can reveal any major abnormality in the lungs or the airway. However, this is relatively less-sensitive imaging technique for the diagnosis of lung cancer.
This technique is generally utilized in case of accumulation of fluid between the pleural membranes (pleural effusion). This can result from lung cancer extending up to these membranes or due to other conditions such as heart failure or infections, etc. The accumulated fluid sample is collected with the help of a needle inserted between the ribs and up to the pleural cavity. The collected sample is then examined under a microscope for the presence of cancer cells.
Laboratory Tests for Biopsy Samples
Following are the techniques used for evaluation of biopsy samples for lung cancer treatment:
Immunohistochemical testing Biopsy block is cut in thin sections and slide is prepared, which is then treated with an antibody against specific proteins in cancer cells. Thereafter, some reagents are added that produce a color change of bound antibody, that can be observed under a microscope.
Fluorescent in situ hybridization (FISH) In this technique, a fluorescent RNA probe is used which binds to a specific gene (a specific sequence of DNA) in the sample. The presence of genetic alterations can be confirmed with the help of fluorescent microscopy. With the development of targeted drugs to treat the different type of NSCLC, the role of molecular testing becomes crucial for the selection of the appropriate lung cancer treatment option.
Following are some tests recommended before starting a targeted or immune therapy for NSCLC:
- epidermal growth factor receptor (EGFR) mutation,
- anaplastic lymphoma kinase (ALK) gene rearrangements,
- ROS1 rearrangements,
- programmed cell death ligand 1 (PD-L1) testing, etc.
Lung/Pulmonary Function Tests
Lung volume measurements are generally performed with the help of spirometer – an instrument that measures air flow during inspiration and expiration. These tests help in estimating the functional capability of the lungs so that the physician/surgeon can estimate how much part of the lung can be safely resected.
What is the Staging of Lung Cancer?
TNM is the staging system used for staging of lung cancer.
Tis – Pre-cancerous changes or carcinoma in situ. No spread to nearby lymph nodes or distant body parts.
T1mi– Cancer is minimally invasive adenocarcinoma </=3 cm in greatest dimension and invasion </=5 mm in greatest dimension. No spread to nearby lymph nodes or distant body parts.
T1a – A tumor </=1 cm in the greatest dimension without invasion of the pleural membrane or main bronchus. No spread to nearby lymph nodes or distant body parts.
T1b – A tumor >1 cm but </=2 cm in the greatest dimension without invasion of the pleural membrane or main bronchus. No spread to nearby lymph nodes or distant body parts.
T1c – A tumor >2 cm but </=3 cm in the greatest dimension without invasion of the pleural membrane or main bronchus. No spread to nearby lymph nodes or distant body parts.T2a – A tumor >3 cm but </=4 cm in the greatest dimension that:
- has invaded into the main bronchus but has not affected the carina (the point where the trachea divides into the 2 bronchi), or
- invades the visceral pleura, or
- is partially choking the airway
T2b – A tumor >4 cm but </=5 cm in the greatest dimension that:
- has invaded into the main bronchus but has not affected the carina (the point where the trachea divides into the 2 bronchi)
- has grown into the visceral pleura
- is partially choking the airway
T3 – A tumor >5 cm but </=7 cm in the greatest dimension
- that has invaded into the parietal pleura, chest wall, phrenic nerve, or the membranes surrounding the heart (parietal pericardium); or
- there are 2 separate primary tumor nodules within the same lobe.
T4 – A tumor >7 cm in the greatest dimension that
- has invaded into the diaphragm, mediastinum, heart, large blood vessels, trachea, recurrent laryngeal nerve, esophagus, backbone, or carina; or
- there is another tumor nodule in the adjacent lobe of the same lung.
N0 – No spread of cancer to nearby lymph nodes
N1 – Cancer has spread to nearby lymph nodes within the lung or along the bronchus or around the area where the bronchus enters the lungN2 – Cancer has spread to subcarinal or ipsilateral mediastinal lymph nodesN3 – Cancer has spread to mediastinal lymph nodes on the other side of the primary tumor, or nodes near the collarbone (supraclavicular nodes)
M0 – Cancer has not spread to distant body parts
M1a – Spread of cancer cells into the pleura or pleural fluid (malignant pleural effusion) or into the pericardium or pericardial fluid (malignant pericardial effusion). M1b – Single tumor deposit in a single distant organ (for example, liver, bones, brain, etc) or to a non-regional lymph node. M1c – Multiple tumor deposits in single or multiple distant organs.
Stage 1 lung cancer may be stage 1A or 1B. Depending on TNM staging discussed above, lung cancer cases included in stage 1 are as following-
T1mi N0 M0
T1a N0 M0
T1b N0 M0
T1c N0 M0
T2a N0 M0
Stage 2 lung cancer may be Stage 2A or 2B, as described below-
T2b N0 M0
T1a-2b N1 M0
T3 N0 M0
Stage 3 may be further classified as Stage 3A, 3B or 3C, as described below-
T1a-2b N2 M0
T3 N1 M0
T4 N0-1 M0
T1a-2b N3 M0
T3-4 N2 M0
T3-4 N3 M0
And finally, Stage 4 may be Stage 4A or 4B as described below-
Any T Any N M1a
Any T Any N M1b
Any T Any N M1c
Staging for Small Cell Lung Cancer
Additionally, SCLC is divided into following 2 stages based on the extent of disease spread and type of treatment approach to be followed:
This means that cancer is only on one side of the chest and might have spread to lymph nodes (including lymph nodes above the collarbone) on the same side. This type of SCLC is generally confined to a specific small region of the lung that can be treated with a single radiation field.
This means that cancer has extensively spread throughout the lung, to other lung, lymph nodes on the other side of the chest, pleural membrane, distant lymph nodes, or distant organ. This type of SCLC cannot be treated with a single radiation therapy and require chemotherapy for their management.
Treatment of NSCLC (Non Small Cell Lung Cancer) according to Stage
The treatment of NSCLC mainly depends on the stage, type, location of the tumor, pulmonary function, performance status of the patient, presence of certain genetic abnormalities, along with other factors.
Following is the preferred treatment approach for different stages of NSCLC, but the final decision is taken after clinical assessment of the patient by an oncologist.
Stage 0 (Tis N0 M0)
Stage 0 NSCLC is limited to the superficial layer of the airway and can be treated by surgery alone as the standard treatment. Sometimes, endobronchial therapies like photodynamic therapy (PDT), laser therapy, or brachytherapy may be employed to treat Stage 0 NSCLC.
Surgery resection with mediastinal lymph node dissection is the standard treatment. Chemotherapy may be added in selected cases. In inoperable cases (poor lung reserve, poor performance status, etc), radiation therapy may be employed as the primary treatment.
Surgical resection with mediastinal lymph node dissection is done, while preoperative chemoradiation may be considered in selected cases. Chemotherapy should be considered after surgery. In inoperable cases, chemotherapy and/or radiotherapy may be given.
Stage III NSCLC treatment generally includes a combination of surgery, radiation therapy, and chemotherapy. The overall treatment approach depends on the size and location of the tumor, the location of the lymph node involved, and overall health status of the patient.
Stage IV (Metastatic disease)
Chemotherapy, targeted therapy or immunotherapy is the mainstay of treatment. Other treatment options like surgery, radiation therapy or bone-directed therapy may be considered for palliation or relief of symptoms.
This brings us to the end of treatment for lung cancer. Now let’s discuss the various treatment modalities for lung cancer in detail.
Surgery for Lung Cancer
Surgery is the treatment of choice for early stage and some advanced stage lung cancers that have not spread to distant body parts and can be completely removed. For early-stage disease, a tumor can be removed with segmentectomy, wedge resection, or sleeve resection, where only a part of the affected lobe is removed.
In case of advanced stage disease, lobectomy (surgical removal of the entire globe) or pneumonectomy (surgical resection of the entire lung) may be required depending on the size and location of the tumor. Surgery can also be employed as a palliative treatment for an advanced-stage disease to relieve airway obstruction by a growing tumor.
Targeted Therapy for Lung Cancer
- Lung cancer is a heterogeneous disease, that is, all individuals with the same cancer type do not contain the same mutations/alterations.
- Targeted anticancer therapy means treatment with specially designed drugs that produce their anticancer effect by selectively modifying a target (key to the growth of cancer cells).
- Examples of such targets include genetic or epigenetic alterations, chromosome/genetic rearrangements, cell-surface proteins/antigens, or certain molecular pathways in the cancer cells that promote growth and are responsible for disease progression.
- Targeted therapy helps in the selective destruction of cancer cells while sparing normal cells, which leads to a decrease in the overall side effects compared to standard chemotherapeutic drugs.
Lung cancer is the leading causes of cancer-related deaths worldwide and is assessed to be the second most frequently diagnosed cancer in men and women. The following table list various targeted drug that has been approved for the treatment of NSCLC:
It is approved for the treatment of patients with unresectable, locally advanced, recurrent, or metastatic non-squamous NSCLC and without a recent history of hemoptysis. It can also be given along with chemotherapy for the treatment of patients with non-squamous NSCLC, and negative or unknown status of ALK/ROS1 rearrangements, sensitizing EGFR mutations, and PD-L1 expression <50%.
In combination with chemotherapy, it is approved for the treatment of patients with metastatic NSCLC whose disease has progressed on or after first-line platinum-based chemotherapy.
Gefitinib and Erlotinib
Both Gefitinib and erlotinib are approved as first-line therapy for patients with locally advanced, recurrent, or metastatic non-squamous NSCLC who have active sensitizing EGFR mutations.
It is an EGFR and HER2 inhibitor approved as the first-line therapy for patients with metastatic NSCLC who have active sensitizing EGFR mutations.
It is an EGFR and T790M inhibitor approved as the first-line therapy for patients with locally advanced or metastatic NSCLC who have sensitizing EGFR mutations. It is also approved as the subsequent therapy for patients with metastatic EGFR and T790M-positive NSCLC who have progressed on erlotinib, gefitinib, or afatinib.
It is an ALK and ROS1 inhibitor approved for the treatment of patients with locally advanced, metastatic, ALK and/or ROS1 rearrangement-positive NSCLC.
It is an ALK and ROS1 inhibitor approved for the treatment of patients with locally advanced, metastatic, ALK and/or ROS1 rearrangement-positive NSCLC who cannot tolerate crizotinib or have progressed on crizotinib treatment.
It is an ALK and MET inhibitor approved for the treatment of patients with locally advanced, metastatic, ALK rearrangement-positive NSCLC. It is also approved for the treatment of patients with metastatic, ALK-positive NSCLC who cannot tolerate crizotinib or have progressed on crizotinib treatment.
It is an ALK inhibitor approved for the treatment of patients with metastatic, ALK-positive NSCLC who cannot tolerate crizotinib or have progressed on crizotinib treatment.
Dabrafenib + trametinib combination is approved for the treatment of patients with metastatic, BRAF V600E positive NSCLC. Single-agent therapy with dabrafenib can also be given to patients with metastatic, BRAF V600E positive NSCLC who cannot tolerate the combination therapy.
Immunotherapy for Lung Cancer
As described above, there are many different types of immunotherapeutic agents. These are used for advanced-stage NSCLC without epidermal growth factor receptor (EGFR) activating mutation, anaplastic lymphoma kinase (ALK) rearrangement, or ROS1 rearrangement. Following immunotherapeutic agents are approved for the treatment of advanced-stage non-small cell lung cancer (NSCLC):
First-line treatment of patients with and who express >/=50% PD-L1. For patients with PD-L1 expression <50% but >1%, it can be combined with chemotherapy for the first-line treatment. Subsequent treatment of patients with metastatic non-squamous or squamous NSCLC and PD-L1 expression levels of >/=1%.
Treatment of patients with advanced-stage metastatic squamous NSCLC and non-squamous NSCLC who have experienced disease progression on or after standard platinum-based chemotherapy (regardless of tumor PD-L1 protein expression).
Combined with chemotherapy with/without targeted therapy, atezolizumab can be given as first-line treatment of patients with metastatic non-squamous NSCLC. Subsequent treatment for patients with metastatic non-squamous or squamous NSCLC and PD-L1 expression levels of >/=1%.
It is recommended as consolidation treatment for patients who have not progressed after concurrent chemoradiation treatment for unresectable stage III NSCLC.
What are the advantages of Immunotherapy for Lung cancer Treatment?
- It is the preferred treatment for the second-line treatment of advanced-stage NSCLC due to improved overall survival rate, longer duration of response, and fewer side-effects compared to standard chemotherapy.
- It can be combined with chemotherapy and targeted therapy for first-line treatment of advanced-stage disease with a better outcome.
What are the disadvantages of Immunotherapy for Lung cancer Treatment?
- Although the immunotherapy is considered safer compared to the standard chemotherapy, it can be associated with certain side-effects.
- Side effects of immunotherapy include fatigue, nausea, itching, skin rash, mouth sores, cough, high blood pressure, fluid build-up in legs, constipation, loss of appetite, joint pain, diarrhea, etc.
- Other less common severe side-effects include immunological reactions such as pneumonitis have also been reported.
- Also, it takes more time to act as compared to other treatment modalities, so it is not a preferred option for patients who require a high reponse rate for symptomatic disease.
Chemotherapy for Lung Cancer
It may be used in the neoadjuvant (prior to surgery), adjuvant (after surgery) and palliative (metastatic disease) settings.
Some chemotherapy drugs that are a part of treatment regimens for lung cancer are-
Radiation Therapy for Lung Cancer
Radiation therapy (or radiotherapy) uses high-energy radiation directed to the affected area to kill cancerous cells. It can be employed either by using an external radiation source (external beam radiation therapy) or by directly placing the source of radiation near the cancer tissue (brachytherapy). Sometimes, it is used as palliative therapy to relieve pain, bleeding, and obstructive problems associated with the advanced-stage disease.
Treatment of SCLC (Small Cell Lung Cancer)
Similar to NSCLC, the treatment for SCLC depends on the stage assigned to the disease with the help of the investigational tests. Very few patients are diagnosed with Stage I SCLC who can be considered the candidates for surgical resection. Thus, chemotherapy with or without radiotherapy remains the mainstay of the treatment.
Preferred treatment approaches for different stages of SCLC:
Chemotherapy with or without radiotherapy is the preferred treatment for the limited-stage SCLC. Surgery may be employed for an early-stage disease, but chemotherapy with or without radiotherapy is generally recommended after surgery due to a high recurrence rate of SCLC. Prophylactic cranial irradiation may also be employed to prevent the spread of disease to the brain as per physician’s discretion.
Chemotherapy with or without radiotherapy is the preferred treatment for the extensive-stage SCLC. Radiation therapy is usually employed for the disease spread to distant organs not directly benefitted from chemotherapy. Prophylactic cranial irradiation may also be employed to prevent the spread of disease to the brain as per physician’s discretion.
Best Lung Cancer Specialist in Delhi
Dr Sunny Garg is a renowned Medical Oncologist in New Delhi with an experience of around 10 years of treating lung cancer patients. He has treated lung cancer patients with Chemotherapy, Targeted Therapy, Immunotherapy and Personalized Cancer Treatment. He is currently practicing at Manipal Hospital, Dwarka.
Diagnostic modalities available at our hospital include CT Guided Biopsy from Lung, Bronchoscopic Biopsy from Mediastinal Lymph Node, Bronchoscopic Biopsy from Lung, Thoracoscopic Lung Biopsy, etc. Other treatment facilities for Lung Cancer available are Lobectomy, Pnemonectomy, Stereotactic Radiosurgery, Lung Resection, Thoracotomy, Mediastinotomy, Visually Assisted Thoracoscopic Surgery, etc.
Call +91 9686813020 for appointment.