Patients diagnosed with stage 4 lung cancer (alk) are already in the late or advanced stage of the disease. In this stage of cancer, the cancer cells which have originated in the lungs have already spread to other parts of the body such as the heart, liver, brain, and other organs. Stage 4 lung cancer is also known as metastatic lung cancer. It may be found on the lymph nodes and multiple organs, but it spreads commonly to the bones, liver and/or brain. When metastatic tumors from the lung are found in other parts of the body, this may still be considered as lung cancer. When cancer progresses to its extensive stage, it spreads to the other parts of the body through the lymph system or bloodstream.
Whenever cancer cells from the lung break away from a tumor and travel through the other parts of the body through the lymph or blood, metastasis occurs. This turns into metastatic lung cancer. Unfortunately, patients receiving a diagnosis of lung cancer are already in stage 4, since symptoms do not develop unless cancer has metastasized.
In about one out of 25 non-small cell lung cancer patients, ALK-positive (anaplastic lymphoma kinase positive or ALK+) lung cancer may be present. Patients 55 years old and below who have never smoked have the highest probability of being diagnosed as ALK+.
Abnormal and uncontrolled growth of the lung cells is caused by ALK mutation, which is a genetic aberration of your lung cell’s DNA. As these cells exhibit uncontrolled mitosis, they can metastasize to other parts of the body.
