The location in the body in which cancer begins or the type of cell the cancer is made of.

Unique identifiers (letters & numbers) assigned to a protocol/clinical trial.

Steps followed in clinical trial research to obtain sufficient evidence that a process would be useful in medical treatment.

There are 5 phases of clinical trials:

• Phase 0:
  The first clinical trials done among people. They aim to learn how a drug is processed in the body and how it affects the body. In these trials, a very small dose of a drug is given to about 10 to 15 people.
• Phase I:
  Tests the safety of a drug in healthy volunteers or subjects with indications. The aim is to find the best dose of a new drug with the fewest side effects. The drug is tested in a small group of 15 to 30 patients. Low doses are given initially to a few patients, higher doses are given in others until desired effect is reached or undesirable effects seen.
• Phase II:
  Further assess safety of a drug in a large sample of patients. The study drug is tested among patients with a specific cancer type and new combinations of drugs may be used.
• Phase III:
  Compare a new drug to the standard-of-care drug. These trials assess the side effects of each drug and which drug works better. Phase III trials enroll 100 or more patients.
• Phase IV:
  Test new drugs approved by the FDA. It studies the side effects caused over time by a new treatment after it has been approved and is on the market. The drug is tested in several hundreds or thousands of patients. This allows for better research on short-lived and long-lasting side effects and safety.

Categories of scientific research, for example intervention or observational.

The institution/organization that is responsible for initiating, managing and often financing the clinical trial but does not conduct the investigation.

Protocol specific requirements that must be met in order for someone to participate in a clinical trial.

National Clinical Trial ID (NCT ID) - unique identifier assigned to clinical trials once registered with clinicaltrials.org.

Status pertains to enrollment ability:

• Active/Recruiting:
  The study is currently recruiting participants.
• Approved-not yet active:
  The study has been approved by the institutional review board (IRB) but not open to enrollment/recruiting participants.
• Closed:
  The study is not open to patient enrollment; closures may be temporary or permanent
• Completed:
  The study has ended normally, and participants are no longer being examined or treated (that is, the last participant's last visit has occurred).
• Enrolling By Invitation:
  The study is selecting its participants from a population, or group of people, decided on by the researchers in advance. These studies are not open to everyone who meets the eligibility criteria but only to people in that particular population, who are specifically invited to participate.
• Temporarily Closed/Suspended:
  The study has stopped early but may start again.
• Withdrawn:
  The study stopped early, before enrolling its first participant.