What Are the Differences Between
Lung Cancer and Mesothelioma?

Mesothelioma is a form of cancer that can affect the lungs. Caused by asbestos, a carcinogenic mineral, mesothelioma is considered rare and is only diagnosed in just over 3,000 people a year. Meanwhile, lung cancer – which can also be caused by asbestos – is one of the most prominent forms of cancer in the world. While both diseases have things in common, they’re quite different and can sometimes get mistaken for each other.

It’s vital to understand the key similarities and differences between the two, especially if you know a loved one who’s been exposed to asbestos in their lifetime or has developed either of these diseases.

Similarities Between Lung Cancer and Mesothelioma

Because of their similarities, some medical professionals may get lung cancer and mesothelioma mixed up. Here’s what the two have in common.

Causes, Stages, and Symptoms

Both are aggressive cancers that affect the respiratory system and have similar causes (prolonged exposure to cancer-causing substances like asbestos). Symptoms of mesothelioma and lung cancer are also comparable, with common reactions including chronic cough, chest pain, lung infections, and shortness of breath.

Additionally, the onset of symptoms for both typically starts in the later stages (stage III and stage IV) when doctors will diagnose them. With less experienced physicians, this is where a misdiagnosis can occur.

Mesothelioma Diagnostic Tests

Doctors use similar methods and tests to diagnose both lung cancer and mesothelioma. Diagnostics can involve imaging tests like X-rays, PET, and CT scans, with follow-up involving tissue biopsies if doctors are concerned with initial imaging results. A biopsy involves making an incision in the affected area and extracting a tissue sample to observe. Other screenings can involve blood and fluid tests extracted from the patient for medical professionals to assess.

Mesothelioma and Lung Cancer Misdiagnosis

When someone with respiratory concerns goes to their doctor for tests and an assessment, the physician’s initial thought might be lung cancer. This is mostly due to the commonality and likeness in illness and symptoms as opposed to the rare mesothelioma.

It’s much less likely for patients to be diagnosed with pleural mesothelioma than lung cancer. About 3,000 patients are diagnosed with mesothelioma a year, compared to lung cancer’s staggering (approximately) 235,760 patients a year, making it one of the main causes of cancer-related deaths in both men and women.

On top of that, imaging test results aren’t always clear, since tumors of both diseases are in areas that are close together with limited view. While tests and screenings can suggest the presence of tumors, a biopsy is the only way medical professionals can officially diagnose most types of cancer. If you believe your lung cancer or mesothelioma stage diagnosis was a mistake, you have a right to go to another doctor for a second opinion.

Other Illnesses

Lung cancer and mesothelioma symptoms also resemble non-malignant illnesses like pneumonia and COPD. If you’re worried a medical professional gave you a misdiagnosis, you’re entitled to a second opinion. Visit a lung disease specialist to take more tests. Having an accurate diagnosis largely affects treatment options, prognosis, and survival.

Differences Between Lung Cancer and Mesothelioma

There are several differences between lung cancer and mesothelioma.


While the causes and symptoms of both diseases are similar, tumor development varies. Malignant lung tumors start their growth inside the lung and quickly spread to outer regions. They appear as separate, but defined masses called nodules.

Mesothelioma tumors stay nearby and aggressively attack a wider section of local tissue. They do this by quickly spreading around the organ lining and coating it as an irregular clump of masses.

Additionally, when mesothelioma tumors develop in the pleural space (lung tissue lining), it’s called pleural mesothelioma. Tumors develop in other areas too, like the lining of the abdomen (peritoneum), and heart (pericardium).

Despite differences, diagnosing pleural mesothelioma or lung cancer still comes with its difficulties.

Prognosis, Treatment, and Recovery

While primary anti-cancer treatments are similar for both illnesses, other variables like the patient’s survival rates or recovery time will differ based on the type of cancer and location of tumors. Other factors that impact prognosis, treatment, and recovery include the patient’s age, sex, stage of mesothelioma, and genetics.

Treatments for cancer patients usually involve one or a combination of chemotherapy, radiation, surgery, and targeted therapies.

Survival rates encompass the percentage of patients that live longer than a set amount of time after their diagnosis. These rates can be calculated on a prognosis of 1 to 5 years after they’re diagnosed with cancer. Lung cancers averaged together (localized, regional, distant), have about 25 percent chance of living 5 years after diagnosis.

In mesothelioma patients, this average falls to about 10 percent. If late-stage lung cancer tumors are localized and haven’t spread, the patient’s 5-year rate jumps from 25 to 65 percent. For localized mesothelioma tumors, that same percentage only goes from 10 to 18.

What’s Next?

If you’ve been diagnosed with lung cancer or mesothelioma from exposure to asbestos or other cancer-causing agents through no fault of your own, you may be entitled to compensation from the companies responsible for the exposure. There are several national laws and regulations in place to protect workers and residents from negligent exposure to toxins in private and public sectors. Fill out one of our case evaluation forms to see if you qualify for legal assistance.