How is the disease diagnosed?

The disease is diagnosed by taking a tissue sample of the lung. There are many ways to collect a tissue sample. Biopsies are obtained wherever the cancer is most accessible. Needle puncture, brush or pinch biopsy is frequently all that is needed. Various ways to collect tissue include:

Through this tissue sample, doctors can tell if the cancer is small cell or non-small cell. Small cell is an aggressive lung cancer deriving from the neuroendocrine cells. It usually has spread cancer cells throughout the body at the time of diagnosis. Frequently a bone marrow biopsy is performed to see if it has spread to the bones. Staging for small cell lung cancer is generally divided into limited disease versus extensive disease.

Non-small cell lung cancer can include all kinds of different cells. Some are flat and scaly, while other disguise themselves as lung cells. These cancers are categorized or staged differently than small cell because this type of lung cancer may be curable. In order to evaluate whether removing all or part of the lung may be feasible, more tests are needed. This includes blood tests, MRI scan of the chest, and bronchoscopy. Other tests, including a bone scan, liver scan or CT scan, may also be needed.

Diagnostic staging is somewhat complex.