gleason sum

Once the prostate is removed during surgery, the pathologist examining the prostate assigns a value to the most common tumor, known as the primary Gleason grade, and a second value to the next most common tumor, known as the secondary Gleason grade. The two grades are added together to get a Gleason score, also known as the Gleason sum.

gleason grade

Physicians characterize the aggressiveness of prostate cancer using the Gleason grading system, which provides an estimate of the cancer's potential to grow and spread to other parts of the body. The pathologist determines the Gleason grade based on how closely the cells of the gland resemble those of a normal prostate. Once the prostate is removed during surgery, a pathologist examining the prostate assigns a grade to the most common tumor, known as the primary Gleason grade, and a second grade to the next most common tumor, known as the secondary Gleason grade. The two grades are added together to get a Gleason score, also known as the Gleason sum.

Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)

Gleason score (GLEE-sun...)

A system of grading prostate cancer tissue based on how it looks under a microscope. Gleason scores range from 2 to 10 and indicate how likely it is that a tumor will spread. A low Gleason score means the cancer tissue is similar to normal prostate tissue and the tumor is less likely to spread; a high Gleason score means the cancer tissue is very different from normal and the tumor is more likely to spread.

Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)

gleason sum

Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)

grade (grayd)

A description of a tumor based on how abnormal the cancer cells look under a microscope and how quickly the tumor is likely to grow and spread. Grading systems are different for each type of cancer.

Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)

pathologist (puh-THAH-loh-jist)

A doctor who identifies diseases by studying cells and tissues under a microscope.

Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)

prostate (PROS-tayt)

A gland in the male reproductive system. The prostate surrounds the part of the urethra (the tube that empties the bladder) just below the bladder, and produces a fluid that forms part of the semen.

Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)

surgery (SER-juh-ree)

A procedure to remove or repair a part of the body or to find out whether disease is present. An operation.

Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)

tumor (TOO-mer)

An abnormal mass of tissue that results when cells divide more than they should or do not die when they should. Tumors may be benign (not cancer), or malignant (cancer). Also called neoplasm.

Source: The National Cancer Institute's Dictionary of Cancer Terms
(http://www.cancer.gov/dictionary)