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Government Funding Lapse
Because of a lapse in government funding, the information on this website may not be up to date, transactions submitted via the website may not be processed, and the agency may not be able to respond to inquiries until appropriations are enacted.

The NIH Clinical Center (the research hospital of NIH) is open. For more details about its operating status, please visit cc.nih.gov.

Updates regarding government operating status and resumption of normal operations can be found at opm.gov.

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Inside a Tumor: What Is Cancer? Video Series

Inside a Tumor: What Is Cancer? Video Series

A cancerous tumor is an abnormal mass of tissue that forms when cells grow and divide uncontrollably and spread into the surrounding area. Learn about other cells found within a tumor and some of their effects. 

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