Polygenic score
Influential genes: CHRNA5,CHRNA3,,CHRNB4
Polymorphisms in CHRNA5 gene have been associated with an increased risk of nicotine dependence, and therefore indirectly with lung cancer.
CHRNA3 is in the same cluster as CHRNA5. Variations in this gene have also been associated with nicotine dependence and an increased risk of lung cancer.
Variants in CHRNB4 gene have been associated with nicotine dependence, and indirectly, with lung cancer risk due to the well-known connection between smoking and lung cancer.
Lung cancer is a type of cancer affecting the cells of the lungs. It occurs when normal cells get out of control and start multiplying uncontrollably. In 2020, lung cancer ranked second in the number of new cases and first in mortality worldwide. [1]
Lung cancer is a type of cancer affecting the cells of the lungs. The lungs are vital organs of the respiratory system. They are located inside the chest cavity and their main function is to exchange oxygen from the environment for carbon dioxide from our body. Cancer occurs when normal cells get out of control and start multiplying uncontrollably.
In the past, the incidence was significantly higher in men, but in recent years there has been an increase in the incidence in women (the reason for this is not fully known). In 2020, lung cancer ranked second in the number of new cases and first in mortality worldwide (for both sexes). [1] At the time of diagnosis, the average age is circa 70 years. [2]
Lung cancer can be divided into two major groups.
In addition to the main types of lung cancer, other malignant neoplasms can occur in the lungs. These include, for example, carcinoids, lymphomas, or sarcomas. Lastly, so-called “secondary tumors” can also occur in the lungs. These tumors spread to the lungs as metastases from distant sites, e.g. the breast, colon, liver, and bone. In absolute numbers this is even more common than primary lung tumors.
The most common symptoms of lung cancer include chronic cough, coughing up blood, shortness of breath, chest pain, hoarseness, weight loss, and fatigue. It is important to realize that these symptoms can also be caused by other diseases, so it is crucial to contact your doctor if you experience any of these. Early detection and treatment can improve outcomes and quality of life.
Lung cancer remains one of the most common types of cancer. In 2020, lung cancer ranked second in the number of new cases and first in mortality worldwide. The estimated number of new cases in Europe in 2020 was 315 054 for men and 162 480 for women. [1]
Risk factors for lung cancer include:
Quitting smoking makes sense at any age, regardless of how long a person has smoked in the past because it significantly lowers the risk of developing lung cancer. By quitting you will also lower your risk of heart attack, stroke, and lung disease (such as COPD). [3]
Familial lung cancer is a typical example of a disease in which the interaction between environment and genetics is crucial. Although certain molecular processes are involved in the disease development (e.g. chromosomal translocations, or gene overexpression), environmental and lifestyle factors need to be taken into consideration as well (e.g. smoking).
The familial occurrence is influenced by several factors, including genetics, similar lifestyles, habits and diet, and environmental factors. Even though genetic factors play a role in disease development, only several genes have been associated with the disease. Furthermore, research based on twin studies has suggested that shared environment and lifestyle factors might be responsible for the onset of lung cancer and that the habit of smoking is the most probable reason. The Lung Cancer Consortium came to the conclusion that people with an affected first-degree relative have approximately 50% higher risk of lung cancer in comparison to people with negative family history. Interestingly, a study of Nordic twins found that heredity might be increasing the risk of lung cancer by about 18%, and the disease has one of the highest estimates (24%) associated with shared environmental influences as well.
Scientific research has been focused on molecular processes that may be involved in lung cancer development. The most frequent change seen in patients with NSCLC is the gain of 2 or more chromosomes per cell. Also, mutations in the K-RAS oncogene (normal gene turned into oncogene which can transform a cell into a tumor cell) are observed in lung adenocarcinoma and its occurrence is estimated to be around 25–40%; these changes are predominantly found in Western populations. Other genetic changes include EGFR gene overexpression, which accounts for about 43–89% of NSCLC cases, B-RAF gene mutations accounting for 6–8% of NSCLC cases, and also HER2 mutations observed in 2–4% of NSCLC cases.[6,7]
Genetic testing allows us to detect whether you have the predisposition to develop this disease. In Macromo, we use polygenic risk scores and causative evidence-based genetic variants for evaluation. The polygenic risk score (PRS) represents the total number of genetic variants that increase an individual's risk of developing a particular disease. All variants across their genome are summed and ranked according to their effect on disease development.
Lung cancer is a type of cancer that often doesn't show any symptoms in the early stages. However, as the disease progresses, there are a few signs that may indicate its presence. These can include:
It's important to note that these symptoms can also be caused by other health issues, so it's essential to consult a medical professional for a proper diagnosis. Early detection of lung cancer can greatly increase the chances of successful treatment and recovery, so it's vital to be aware of the potential signs and seek medical attention if any of them persist.
Diagnosis of lung cancer typically involves a variety of tests and procedures. The first step is often a physical exam and a review of the patient's medical history, followed by imaging tests such as X-rays, CT scans, and MRI scans of the lungs and surrounding area. A biopsy, in which a small sample of tissue is removed and examined under a microscope, is usually required to confirm a lung cancer diagnosis. Blood tests may also be performed to check for certain biomarkers that can indicate the presence of lung cancer. Once a diagnosis has been confirmed, the stage and type of lung cancer should be determined, as it is essential for proper treatment.
The therapy of lung cancer depends on several factors, including the stage and type of cancer and the patient's overall health. Treatment options typically include surgery, chemotherapy, radiation therapy, targeted therapy, and immunotherapy.
In some cases, a combination of these therapies may be used. The treatment plan for lung cancer is highly individualized.
There is no definitive way to prevent cancer. But there are measures that can reduce the risk of developing it. [2] Lifestyle plays an important role in the development of lung cancer, as cigarette smoking is the primary cause of lung cancer, and quitting smoking is the most effective way to prevent the disease. Second-hand smoke (the smoke that results from burning tobacco or the smoke breathed out by others), air pollution, and workplace hazards (e.g. asbestos) also greatly increase your risk. Even simple lifestyle changes such as a balanced diet, regular exercise, and avoiding exposure to harmful substances can make a big difference to your potential risk of developing the disease.
There are also studies suggesting that a diet rich in vegetables and fruits, especially cruciferous vegetables (cabbage, radish, horseradish, broccoli, cauliflower, etc.) may have some protective effect against lung cancer. However, the results of these studies have not yet been conclusively confirmed. [4]
Participation in regular health check-ups and screening programs will ensure the best prognosis. Different countries may offer different programs - for example, in the Czech Republic, there is a lung cancer screening program aimed at at-risk patients (heavy smokers) aged 55-75, selected by their GP. [5]
The prognosis for lung cancer varies greatly depending on the stage of cancer at the time of diagnosis, the type of lung cancer, and the patient's overall health. In general, the earlier the cancer is diagnosed and treated, the greater the chance of survival. Unfortunately, many cases of lung cancer are not detected until later stages, which can make treatment more difficult and reduce the chances of survival. In addition, some types of lung cancer are more aggressive and less responsive to treatment than others.
Get the guidelines for a healthier and longer life. With Macromo tests, you'll learn your health risks and how to prevent them.
Continue to Shop[1] Cancer Today. (n.d.). Retrieved February 17, 2023, from https://gco.iarc.fr/today/online-analysis-table?v=2020&mode=cancer&mode_population=continents&population=900&populations=900&key=asr&sex=0&cancer=39&type=0&statistic=5&prevalence=0&population_group=0&ages_group%5B%5D=0&ages_group%5B%5D=17&group_cancer=1&include_nmsc=1&include_nmsc_other=0
[2] Lung Cancer Statistics | How Common is Lung Cancer? (n.d.). Retrieved February 17, 2023, from https://www.cancer.org/cancer/lung-cancer/about/key-statistics.html
[3] Lung cancer - Symptoms and causes - Mayo Clinic. (n.d.). Retrieved February 17, 2023, from https://www.mayoclinic.org/diseases-conditions/lung-cancer/symptoms-causes/syc-20374620
[4] Malhotra, J., Malvezzi, M., Negri, E., la Vecchia, C., & Boffetta, P. (2016). Risk factors for lung cancer worldwide. European Respiratory Journal, 48(3), 889–902. https://doi.org/10.1183/13993003.00359-2016
[5] Od nového roku doporučí praktici silným kuřákům bezplatný screening plic – Ministerstvo zdravotnictví. (n.d.). Retrieved February 17, 2023, from https://www.mzcr.cz/tiskove-centrum-mz/od-noveho-roku-doporuci-praktici-silnym-kurakum-bezplatny-screening-plic/
[6] Benusiglio PR, Fallet V, Sanchis-Borja M, Coulet F, Cadranel J. Lung cancer is also a hereditary disease. Eur Respir Rev. 2021;30(162):210045. doi:10.1183/16000617.0045-2021
[7] Kanwal M, Ding XJ, Cao Y. Familial risk for lung cancer. Oncology Letters. 2016;13(2):535-542. doi:10.3892/ol.2016.5518