Official websites use .gov
A
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government organization in the United States.
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A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
A typical projection X-ray chest image with two marks made by a radiologist indicating locations of suspected tumors. The upper circle represents a true tumor (true positive), and the bottom circle represents a false positive (false alarm) report (not a true tumor).
