Even if you do not smoke, you may be exposed to secondhand smoke. This type of smoke can come from:

• Someone breathing out smoke while smoking

• A burning cigarette, cigar, or pipe

You may also hear secondhand smoke called passive or involuntary smoke, tobacco smoke pollution, or environmental tobacco smoke.

There is no safe level of exposure to secondhand smoke. Even brief moments around secondhand smoke can harm a person’s health. And the risk of health problems is greater with more exposure.

Proton therapy is a type of radiation therapy that uses protons rather than x-rays. It painlessly delivers radiation to treat some types of cancer. Proton therapy is a promising new type of cancer treatment, but its possible benefit over traditional radiation therapy is still being studied. Research is ongoing in clinical trials to see how it compares.

In general, proton therapy has fewer side effects than other types of radiation therapy. This is because it can be targeted more directly at the tumor and does less damage to other tissue.