The condition and the treatment
Cancer affecting the lungs is grouped into 2 main types depending on how it looks under the microscope: small-cell lung cancer and non-small-cell-lung cancer.
Lung cancer tissue can be tested to check whether the cells have EGFR-TK mutations (changes). If they do, the cancer is 'EGFR-TK mutation-positive'. The EGFR-TK mutations make the cancer more likely to respond to drugs that block the EGFR (called EGFR-TK inhibitors).
Cancer that is described as being locally advanced or metastatic has spread to the surrounding tissues or other parts of the body.
Afatinib (also known as Giotrif) is an anticancer drug. It works by stopping the cancer growing.
NHS Choices (www.nhs.uk) may be a good place to find out more.