Biology of Young Lung Cancer Study: The YOUNG LUNG Study

The purpose of this research study is to learn more about lung cancer (NSCLC or SCLC) diagnosed in adults at ages 45 or younger.

This research study looks to enroll as many people diagnosed with lung cancer at 45 years old or younger in order to: * Better understand causes of lung cancer in individuals 45 years old and younger, which is a rare disease * Better estimate lung cancer risks and potential risk factors for lung cancer in individuals 45 years old and younger * Examine tumor (somatic) or normal (germline) genetic changes that may be shared among young lung cancer patients * Improve opportunities for screening and treatment of lung cancer in individuals 45 years old and younger Study procedures will include: * Collecting information from participants' medical record and two (2) short questionnaires * Collecting blood and/or saliva samples * Collecting tumor tissue samples (optional) It is expected that about 500 people will take part in this research study. Participants will be in this study until it closes or the participant withdraws consent.