Lung Cancer

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The leading cause of lung cancer is smoking; however, nonsmokers may develop lung cancer from other sources, such as asbestos or radon gas. Lung cancer also may develop from the spread of cancer (metastasis) from other parts of the body.


Lung cancer is one of the most misdiagnosed types of cancer. Misdiagnosis can lead to delayed detection, allowing for continued growth of the disease and an increase in the difficulty of treatment.

Some mistakes made by doctors or health care professionals that have led to an incorrect lung cancer diagnosis are:

  • Failing to perform the necessary tests (MRIs, biopsies, X-rays)
  • Mistaking lung cancer symptoms for another condition
  • Over-diagnosing smokers or under-diagnosing nonsmokers
  • Falsely diagnosing a tumor as benign
  • Poor assessment of test results