Prostate Cancer

What Is Prostate Cancer Staging?

If you are diagnosed with prostate cancer, it is important to know just how far the disease has progressed. This is determined by evaluating the stage of the cancer.

Oncologists (physicians who specialize in the treatment of cancer) have developed several systems to classify the extent of the cancer. This is done by looking at its stage of development and the arrangement of cancer cells. By determining the stage of the cancer, doctors can come up with the most appropriate treatment plan.

• Stage A – In this earliest stage, cancer has just been identified by PSA tests and biopsy. No prognosis can be made until it is known how widely spread the cancer cells may be.
• Stage B – In this stage, it is known that cancer is in several places within the prostate.
• Stage C – In this stage, cancer has spread throughout the prostate and may have spread to nearby tissue or the bladder.
• Stage D – Cancer has spread beyond the prostate and nearby tissues. If the cancer is still only within the pelvic area, the stage is D1. If it has spread to the bone, it is stage D2.

Gleason Score

Oncologist have developed another set of staging criteria called the Gleason Score. The Gleason Score is based on the arrangement of cancer cells in tumors as seen under the microscope by the pathologist. The lower the score, the better.

• The lowest possible Gleason score is 2.
• Typical Gleason scores are between 5 and 7.
• Gleason scores between 7 and 10 are high.

TNM Staging

Physicians also stage prostate cancer by the TNM system, a universal scoring system that looks at how far the cancer has spread. To get the TNM staging the oncologist looks at:

• The tumor size (T staging)
• The lymph node involvement (N staging)
• The presence of cancer in other parts of the body, or its metastasis (M staging)

T staging goes from T1 to T4, with some sub-stages:

• T1 means the cancer cannot be seen or felt, but a biopsy has confirmed its presence.
  • T1a means cancer is present in 5 percent or less of the prostate tissue that has been examined.
  • T1b means cancer is present in more than 5 percent of the prostate tissue.
• T2 means the cancer is confined to the prostate.
  • T2a means that cancer is on one side of the prostate.
  • T2b means that cancer is on both sides.
• T3 means the cancer spread beyond the prostate to nearby tissues and organs.
  • T3a means cancer is not found in the seminal glands (which contribute toward the production of semen).
  • T3b means that it has spread to the seminal glands.
• T4 tumors have spread to other organs, such as the bladder or rectum.

N staging goes from N0 to N1:

• N0 means that cancer has not spread to the lymph nodes.
• N1 means that cancer has been found in the lymph nodes.

M staging goes from M0 to M1, with some sub-stages:

• M0 means that cancer has not spread to distant tissues.
• M1 means that cancer has been found in distant tissues.
  • M1a means it has been found in lymph nodes beyond the pelvic area.
  • M1b means it has been found in the bone.
  • M1c means it has been found in other sites.