Neoplasia is the uncontrolled, abnormal growth of cells or tissues in the body, and the abnormal growth itself is called a neoplasm or tumor.  It can be benign or malignant.  Benign neoplasms do not grow aggressively, do not invade the surrounding body tissues, and do not spread throughout the body.  Malignant neoplasms, on the other hand, tend to grow rapidly, invade the tissues around them, and spread, or metastasize, to other parts of the body.  The word “tumor” or “mass” is often used to describe the actual swelling or other physical appearance of a neoplasm.  The word “cancer” is often confused with neoplasia, but only malignant neoplasms are truly cancers.

50% Survival Time or Mean Survival Time is the time in which half of the study subjects (or 50%) remain alive.  The time is measured beginning either at diagnosis or the start of treatment.  The survival time can be a little misleading in that maximum survival time is not simply twice the mean as some subjects can live considerably longer (or shorter) but is an often used measure in cancer prognosis. 

Chemotherapy is one of varying types of therapy given to cancer patients to combat the disease.  The types of treatment options available can be the use of drugs (chemo), radiation, or surgical removal of the neoplasm.  Depending upon the type of cancer, one or any combination of treatment options can be used

Remission Check is the point in which cancer patients are routinely checked for recurrence of disease.  Depending upon the type of cancer, the Remission Check can be at varying intervals. 

Rescue Therapy is the therapy (chemo, radiation, or other) delivered to a cancer patient that failed the Remission Check or has recurring disease.