Your physician may perform additional tests to determine if the prostate cancer has spread and to understand how fast it is growing.

Bone Scans determine if cancer has spread to the bones. A physician conducts a safe diagnostic imaging test to determine whether  cancer appears in the bones.

CAT or CT Scan

Computerized Tomography is a series of x-rays that produce cross-sectional pictures of the body that may help your physician determine if prostate cancer has spread.

Magnetic Resonance Imaging (MRI)

MRI is similar to a CAT scan except it uses magnetic fields instead of x-rays to create detailed, cross-sectional pictures of selected portions of the body.

Tumor Grading

A cancer cell’s ability to mimic a normal prostate gland cell is called differentiation. Cancers that look similar to normal tissue are “well differentiated,” while those appearing very different are “poorly differentiated.” Cancers in between these two are “moderately differentiated.” The Gleason system uses this information to grade tumors, indicating how fast the cancer is growing. A pathologist assigns a Gleason grade ranging from 1 through 5 based on the level of differentiation. The more dissimilar cancer cells appear from normal prostate tissue and the more they seem to have spread haphazardly throughout the prostate, the higher the Gleason grade assigned.

  • Gleason Grades 1 and 2. Cancer cells closely resemble normal prostate tissue and are well differentiated. Cancer cells will probably have a biological behavior relatively close to normal and may not be aggressively malignant.
  • Gleason Grade 3. The most common grade assigned. These cancer cells are moderately well differentiated.
  • Gleason Grade 4. May indicate development of a more advanced tumor. This grade indicates the first main disruption and loss of normal prostate gland tissue architecture. This is the main class of poorly differentiated prostate cancer, and its distinction from Grade 3 is the most important decision made by a pathologist.
  • Gleason Grade 5. The cells do not resemble normal prostate cancer tissue and do not look different from undifferentiated cancers that might occur in other parts of the body. This grade is generally associated with a poor prognosis. It is less common than Grade 4 and seldom seen in men with an early prostate cancer diagnosis.

When examining the specimen, a pathologist also tries to identify two architectural patterns and assigns a grade to each one. There may be a primary — or most common pattern — as well as a secondary pattern, or there only may be a single, pure grade. Added together, the two numbers create the Gleason score, also called a Gleason sum, which quantifies how aggressive the cancer appears. The Gleason score ranges between 2 and 10, with 2 being the slowest growing cancer and 10 the most aggressive. Most localized prostate cancers are in the intermediate score range of 5 to 6.

Cancer Staging: If tests indicate the presence of prostate cancer, the doctor needs more information to determine how much of the gland is affected, whether it has spread to nearby tissues or if it has metastasized to other parts of the body. Various diagnostic tests indicate the disease stage, a crucial factor in choosing treatment options.

There are two commonly used staging systems. The TNM (Tumor, Nodes, Metastasis) Staging System classifies tumors based on size, extent of spread to the lymph nodes and extent of spread to other parts of the body. The second uses Stage I through IV or A through D to classify tumors. These two systems are often combined.

  • Stage I (A) The cancer cannot be detected by rectal exam alone and causes no symptoms.
  • Stage II (B) The tumor is felt in a rectal exam or detected by a blood test, but there is no evidence it has spread outside the prostate.
  • Stage III (C) The cancer has spread outside the prostate to nearby tissues.
  • Stage IV (D) Cancer cells have spread to lymph nodes or to other parts of the body.

Still have questions? Call us at 1-800-458-4372 to speak with one of our prostate cancer information specialists.