Primary Lung Cancer
Primary lung cancer is a malignant (cancerous) growth that begins in the cells of the lung itself, rather than spreading from another part of the body. Over time, these abnormal cells grow in an uncontrolled way and can form a mass, extend into nearby structures, or spread (metastasize) to distant organs. Lung cancer is one of the most common cancers worldwide, but earlier detection and modern treatments continue to improve outcomes for many people.
What is it?
Primary lung cancer develops when cells within the lung acquire genetic changes that cause them to grow and divide without normal control. These tumors can range from small nodules identified on screening CT to larger masses that cause symptoms. The two major categories are non-small cell lung cancer (NSCLC), which accounts for about 85% of cases, and small cell lung cancer (SCLC), which represents roughly 15% and often grows and spreads more rapidly.
Most lung cancers begin in the airways or in the outer regions of the lungs where inhaled substances make contact with lung tissue. Smoking remains the largest risk factor, but lung cancer can also develop in people who have never smoked. Other contributing factors include secondhand smoke, radon exposure, air pollution, occupational exposures, and family or genetic risk.
Important to Know
Symptoms may be subtle in early stages and can resemble common respiratory conditions. A persistent or changing cough, coughing up blood, chest pain that worsens with breathing or coughing, hoarseness, or unexplained weight loss should prompt medical evaluation. Some people have no symptoms, and lung cancer is discovered incidentally or through screening CT scans.
CT imaging is central to evaluating lung cancer, helping determine the size and location of the tumor and whether it has spread to lymph nodes or other organs. PET/CT, MRI, and other tests may be used to establish the stage of disease. Red flags that require urgent attention include sudden or significant coughing up of blood, severe shortness of breath, chest pain at rest, or new neurologic symptoms such as weakness or confusion.
Treatment options continue to expand. Depending on the type and stage, care may include surgery to remove the tumor, radiation therapy, chemotherapy, targeted therapies that address specific tumor mutations, and immunotherapy that helps the immune system recognize and attack cancer cells. A multidisciplinary team approach helps personalize treatment to each individual’s needs.