Lung cancer trends, survival and prevention

Lung cancer is one of the most aggressive cancer worldwide. It is a disease in which malignant cells form in the tissues of the lung and is the leading cause of cancer in both men and women. The lungs are a pair of cone-shaped breathing organs in the chest and each lung has sections called lobes. The left lung has two lobes and the right lung has three lobes. And in these organs is where the lung cancer can be subdivided in two types: small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC).

Avoiding some risk factors can prevent the development of this dangerous disease:

 

Table 1.1 Risk factors for lung cancer (https://www.cancer.gov)

In the table 1.1 are listed the principal risk factors to the lung cancer development. In the recent years, the B-carotene and retinol were found to increase the risk in smokers. In the CARET, Clinical And Retinol Trial Efficacy, was a randomized, double-blind, placebo-controlled trial of the cancer prevention efficacy and safety of a daily combination of 30mg of beta-carotene and 25,000 IU of retinyl palmitate in 18,314 persons with a high risk for lung cancer. The study started in 1985 and the study was stopped in January 1996, because of definitive evidence that vitamin A has no benefit and that has a harmful effect in both lung cancer incidence and mortality. In resume, the results showed that those patients whom received the Vitamin A had no chemopreventive benefit and had excess lung cancer incidence and mortality. These results were consistently with those found in Alpha-Tocopherol Beta-Carotene Cancer prevention Study in 29133 male smokers in Finland.

 

 

Table 1.2 Factors that can prevent to develop lung cancer.

In the table above (Table 1.2) is listed the most common factors that can help to prevent lung cancer development. Is important to stop smoking since it has been strongly related as the principal cause. In smokers that have received treatment for lung cancer, quitting smoking lowers the risk of new cancer; plus, the use of nicotine replacement products and antidepressant therapy have helped smokers quit for good. However, we need to remember that the probability of preventing lung cancer will depend on how many years and how much the person smoked and the length of time since quitting. For example, after a person stop smoking for 10 years, the risk of lung cancer decreases 30% to 60%.

In the paragraph above we talk about the importance of no smoking, but what happen when we never smoke? Well, the lung cancer incidence among never smokers has increased in recent decades with 10-30% of all lung cancers, where exposure to residential radon is the leading cause of this disease. Since there is not much information about the lung cancer survival in never smokers that’s why Casal-Mouriño, et al (2019) published an article where they evaluated the survival in this group and if there is difference regarding smokers, through a review applying predefined inclusion and exclusion criteria. 17 studies were included and the next results were obtained:

  • Never smoker lung cancer patients seem to experience longer survival times than do smokers or ex-smokers.
  • Lung cancer in never smokers displays distinctive characteristics.
  • More frequent in women
  • More frequently diagnosed at more advanced stages
  • Predominant histologic type is adenocarcinoma

More studies need to be done for this unexpected group; but even though lung cancer has proved to be a very aggressive disease and depending of the type of lung cancer, it will be the therapy that needs to be followed. However, even we avoid the most common risk factors, we need to be always alert about any rare symptom, go with our doctor and always follow the instructions.

In Althian, we have several years working with lung cancer clinical trials. Even the most recent therapies have been efficient to some patients. If we can avoid or lower the risk of lung cancer development, that would be the best solution. We have plenty experience managing these types of protocols, so please contact us to share the experience we have.