Lung Cancer, from the CureRays guide library.

Lung cancer begins when cells in the lungs grow out of control; found early, many cases can be cured — and low-dose CT screening is finding more of them in time.

What it is.

The lungs are two sponge-like organs that bring oxygen into the body and remove carbon dioxide. Lung cancer starts when cells lining the airways or air sacs grow uncontrollably, forming a tumor that can block breathing, invade nearby tissue, and spread elsewhere. Smoking is the biggest cause, but lung cancer also occurs in people who never smoked. Caught early — often through low-dose CT screening — small lung cancers can frequently be cured without surgery.

How radiation treats it.

Radiation uses focused high-energy x-rays to damage cancer-cell DNA so the cells can no longer divide. Healthy cells repair this damage better than cancer cells, so treatment clears cancer while sparing normal tissue. With SBRT, advanced imaging tracks the tumor as it moves with each breath, so the beams stay locked on a small target. Sessions are painless and brief; common side effects are some fatigue, and occasionally a temporary cough, sore throat, or mild swallowing discomfort that settle after treatment.

The ways we can treat it.

Stereotactic body radiation therapy (SBRT). Delivers a few very precise, high-dose treatments (often 3-5 sessions) to a small early tumor. Cure rates rival surgery for stage I cancer, and it is the standard option when surgery is too risky.

Conventional/curative external-beam (IMRT/IGRT). Shapes the dose to larger or more central tumors over several weeks, usually alongside chemotherapy for stage III disease, while sparing the heart, normal lung, and spinal cord.

Prophylactic & palliative radiation. In small cell lung cancer, low-dose brain radiation can prevent spread; targeted radiation also relieves symptoms like pain, bleeding, or airway blockage.

Questions we hear often.

I never smoked — can I still get lung cancer? Yes. A meaningful share of lung cancers, especially adenocarcinoma, occur in people who never smoked. Causes can include radon, secondhand smoke, air pollution, and inherited gene changes.

Can lung cancer be cured without surgery? Often, yes. For early tumors, stereotactic radiation (SBRT) offers cure rates close to surgery in just a few painless sessions.

Should I be screened? If you are roughly 50-80, smoke or recently quit, and have a significant smoking history, a yearly low-dose CT scan can catch cancer early. Ask your doctor whether you qualify.

This guide is informational only. It is not medical advice — please confirm anything here with your care team.