COPD and Lung Cancer: An Overview

Introduction:

COPD (Chronic obstructive pulmonary disease) and lung cancer are two different lung diseases and are the common causes of morbidity and mortality around the globe. Both conditions frequently coexist in people and share similar risk factors. COPD is the third-most prevalent cause of death, affecting around 300 million individuals globally. Lung cancer is the most common cause of cancer-related death and is one of the most often diagnosed cancers in men worldwide. This article briefly explains COPD, lung cancer, the link between the two conditions, and their management strategies.

What Is COPD?

Chronic obstructive pulmonary disease, or COPD, refers to a group of conditions that interfere with the airways and make breathing difficult. Since COPD is a progressive disease, at first, the symptoms appear gradually but get worse over time, making it difficult to perform daily tasks.

It involves two main conditions;

• Emphysema: Emphysema is damage to the walls of air sacs (alveoli) in the lungs. In normal lungs, during breathing air in each air sac is filled up with air. And during breathing out, air sacs shrink as air goes out of the lungs. In the case of emphysema, the lungs are not able to expel air out of air sacs, making breathing difficult.

• Long-Term Bronchitis: Long-term bronchitis is the constant irritation and inflammation in the lining of bronchial tubes. These tubes are responsible for carrying air from and to the air sacs in the lungs. The constant irritation and inflammation lead to a buildup of thick mucus in these tubes, making it difficult to breathe.

Symptoms of COPD may include:

• Shortness of breath during physical activities.

• Wheezing.

• Chest tightness.

• Cough with sputum.

• Frequent respiratory infections.

• Weakness.

• Unintended weight loss.

• Swelling in legs, ankles, or feet.

Smoking is the most common cause of COPD. However, non-smokers can also develop COPD due to environmental pollutants or genetic factors.

What Is Lung Cancer?

Lung cancer is a type of cancer in which the abnormal cells in the lungs grow uncontrollably. These abnormal cells form a mass that makes breathing difficult. It is a serious health issue that can cause death. About 85 percent of cases of lung cancer are caused by smoking, making it the primary cause of the disease.

Symptoms of lung cancer may include:

• Cough.

• Chest pain.

• Shortness of breath.

• Loss of appetite.

• Weight loss.

• Tiredness.

What Is the Link Between COPD and Lung Cancer?

COPD and lung cancer are lung disorders, but they are not the same. However, the disorders are closely related to one another, involving the same risk factor, biological mechanism, and some environmental factors.

1. Shared Risk Factors:

• Cigarette smoking is the cause of both lung cancer and COPD.

• COPD is a separate risk factor for lung cancer.

• The risk of getting lung cancer in smokers with COPD is five times more than in people with normal lung function.

2. Oxidative Stress: Oxidative stress contributes to both lung cancer and COPD. Oxidative stress is caused by free radicals such as reactive nitrogen and oxygen species (RNOS).

Source of RNOS:

• Smoking.

• Mitochondrial dysfunction.

These free radicals are harmful molecules that damage the cell by causing mutation in its DNA, which leads to uncontrolled cell growth (cancer) and also triggers the production of inflammatory mediators, contributing to COPD.

3. Telomere Shortening: Thetelomere is a region located at the end of human chromosomes. Normally, with age, these telomeres shorten. When telomeres are shortened beyond their crucial point, the cells are unable to divide further (senescence phase). In some cases, cells bypass the senescence phase and continue to divide despite a short telomere. The telomeres are very short in these cells. Reduced telomere length is linked to both COPD and lung cancer. Also, cigarette smoking can cause telomere shortening.

4. Genetic Link: Some studies have shown that specific regions on chromosomes, such as chromosome 6, are linked to both the risk of COPD and lung cancer, suggesting that some common genetic factor might be involved in both conditions. Furthermore, other studies have shown that certain genes like CHRNA3 and CHRNA5 have been identified as potential risk factors for both COPD and lung cancer.

5. Occupational and Environmental Air Pollution:

• Dust, pollutants, and exposure to certain metals have been ignored as risk factors for COPD. Comparatively, the primary cause of lung cancer is linked to occupational exposures such as asbestos fibers and radon.

• In low-income countries, burning biomass fuels, such as coal and wood, for cooking and heating is a major cause of lung cancer and COPD.

• Cooking oil fumes and poor kitchen ventilation have been linked in certain studies to an increased risk of COPD and lung cancer.

What Is the Management of COPD and Lung Cancer?

1. Early Detection and Screening: Early detection of COPD and lung cancer is important for improving treatment outcomes.

2. Smoking Cessation: Quitting smoking is a crucial step for both COPD and lung cancer management. Smoke cessation not only stops further damage to the lungs but also improves overall health and treatment outcomes.

3. Treatment For COPD:

• Medications - Inhalers or tablets to facilitate easy breathing.

• Pulmonary Rehabilitation - An individualized program for education and exercise.

• Surgery or a Lung Transplant - In some cases of COPD, surgery might be an option to improve breathing.

4. Treatment For Lung Cancer:

Treatment of cancer depends upon overall health, type of cancer, and stage of cancer.

• Surgery– Surgery involves the removal of the cancerous part and margin of healthy tissue.

• Radiation Therapy– It involves the use of high-powered energy beams from X-rays and protons that kill the cancer cells.

• Chemotherapy– This therapy involves the use of certain drugs to kill cancer cells.

• Targeted Drug Therapy– Targeted drug therapy focuses on the defects found in cancer cells. Specific medications are used to block the abnormalities in cancer cells and cause the cancer cells to die.

• Immunotherapy– Immunotherapy therapy involves certain medications that stimulate the immune system to target the cancer cells and kill them.

Conclusion:

COPD and lung cancer pose a significant global health concern, both sharing common risk factors and biological mechanisms. With early detection, smoking cessation, and an individualized treatment approach, there can be an improvement in overall respiratory health and patient outcomes.