Lung cancer and mesothelioma have much in common. In fact, it is not unusual for people to confuse the two types of cancer. They have similar causes and symptoms, but there are several very important differences.

Cancer is a complex group of diseases in which a cell’s control mechanisms misfire, causing the cell to reproduce unaccountably, causing damage to other cells by consuming resources and infiltrating other tissue. Human cancers are chiefly classified based on where they start in the body, though researchers are beginning to understand the hundreds, perhaps thousands, of underlying biological pathways that can lead to cancer.

Mesothelioma and lung cancers start in different parts of the body. Lung cancers include a number of related cancers that start in various parts of the lungs. In mesothelioma, the cancer starts in the mesothelium. Mesothelium are membranes throughout the body that develop from the same tissue layer when a person is a fetus. These membranes line body cavities. The most common and well-known form of mesothelioma starts in the pleura, a membrane that encloses the chest cavity, though more rare forms of mesothelioma are reported in other mesothelium throughout the body.

Since both lung cancer and the most common forms of mesothelioma develop in the chest, both cancers cause a constellation of similar symptoms. Though they vary by individual and the specific cancer, this typically includes shortness of breath, chest pain, coughing up blood, and fluid in the chest.

Another major difference involves the common causes of these cancers. Healthy cells become cancerous when the mechanisms that regulate their growth malfunction. DNA, which controls everything within a cell, is one of the main vulnerabilities. Substances that can damage DNA and promote cancer are called carcinogens. Both natural and synthetic chemicals can be carcinogens. Chemicals found in tobacco products are one of the leading causes of lung cancer. However, exposure to asbestos is also a risk factor for lung cancer, and the combination of smoking and asbestos exposure is a huge risk factor for lung cancer. Mesothelioma, on the other hand, is almost universally found in patients with a history of asbestos exposure.

Asbestos, a risk for both lung cancer and mesothelioma, came into widespread use during the Industrial Revolution. It is a naturally-occurring mineral. This mineral resists both temperature changes and fire, making it a useful building material.

Workers exposed to asbestos typically worked in a variety of occupations. Some worked directly in the asbestos industries, including miners and machinists who dug the material out of the ground and worked it into usable product. Others, like construction workers and shipwrights, came into contact with the material in the course of their jobs, since its properties made the mineral very useful as a fireproof insulator. Though the United States phased out and banned asbestos during the 1970s and 1980s, cancers like asbestos lung cancer and mesothelioma typically manifest decades later, and multimillion dollar lawsuit settlements and verdicts are still being paid out over asbestos cancers.