The presence of tumor was the cause of death in 30 percent of people with lung cancer, a statistic that was further broken down to 4 percent of people dying from “tumor load” in the lungs, and 26 percent due to “tumor load” from metastases.
Infections were responsible for death in 20 percent of the patients. For 12 of these people, it was pneumonia; for 8, it was sepsis.
Complications of Metastatic Disease
When lung cancer spreads to other regions of the body, it can interfere with the normal functioning of those organs. For example, if lung cancer has spread to the brain, it may interfere with normal brain functions such as the ability to walk, talk, and swallow, or even result in a hemorrhagic stroke. The spread of lung cancer to the liver can interfere with the liver’s ability to do its job of removing toxins from the body, and the buildup of toxins may in turn cause death (this is usually painless, as people slowly become less alert).
Pulmonary hemorrhage, or bleeding into the lungs, was responsible for 12 percent of deaths. Even a small amount (more than a teaspoon or two) of bleeding in the lungs (which often results in the symptom of coughing up blood) can be a medical emergency.
Blood clots (deep venous thrombosis) in the legs that break off and travel to the lungs (pulmonary emboli) caused 10 percent of lung cancer deaths in this study—a significant finding, as blood clots are sometimes preventable, and often treatable.
Looking at the causes of death with lung cancer from a functional standpoint, respiratory failure was the immediate cause of death 38 percent of the time, whether caused by tumor load, pneumonia or hemorrhage. It’s important to note that most people had more than one mechanism contributing to death.
Other Possible Causes of Death with Lung Cancer
This was just one study. Looking at the causes of death from all types of cancer, other possible causes may include:
Complications of treatments such as chemotherapy and radiation therapy A low white blood cell count from chemotherapy, with a resultant overwhelming infection, is not uncommon for those in that later stages of cancer.
Medical and medication errors. Unfortunately, hospital errors rank far too high in ultimate causes of death. The risk of these can be minimized by asking a lot of questions, asking further questions if you do not understand something or are uncomfortable with something that is happening, and taking an active role in the care of your loved one.
Complications of surgery, such as anesthesia complications and bleeding.
Conditions unrelated to cancer, such as heart attacks due to blockages unrelated to cancer.