Prostate Cancer: Staging and Treatment

What is staging for cancer?

Staging is the process of learning how much cancer is in your body and where it is. Tests like biopsy, digital rectal exam, bone scan, transrectal ultrasound (TRUS), prostate-specific antigen (PSA) level in your blood, CT, MRI, and PET scan may be done to help stage your cancer. Your providers need to know about your cancer and your health so that they can plan the best treatment for you.

Staging looks at the size of the tumor, where it is, and if it has spread to other organs. The staging system for prostate cancer is called the “TNM system,” along with the Gleason score. The staging has three parts, plus the Gleason score:

• T-describes the size/location/extent of the "primary" tumor in the prostate.
  • Prostate cancer has two types of “T” categories:
    • Clinical T (cT): cT is your provider’s best guess of the extent of your cancer. It is based on physical exam (digital rectal exam), biopsy, and any imaging tests you have had.
    • Pathologic T (pT): If you have surgery to remove your prostate, your provider can use pT to determine the extent of the cancer. pT is likely more accurate than cT because the whole prostate can be looked at after it is removed.
• N-describes if the cancer has spread to the lymph nodes.
• M-describes if the cancer has spread to other organs (called metastases).
• G- Describes the Gleason score and looks at the PSA and the histologic grade of the tumor. The Gleason score ranges from 2 to 10. 2 means the tumor cells look more like normal prostate tissue. 10 means the tumor cells look most abnormal compared to normal prostate cells.

How is prostate cancer staged?

Staging for prostate cancer is based on:

• The size of your tumor on imaging tests and what is found after surgery.
• Any evidence of spread to other organs (metastasis).
• Surgery to test if your lymph nodes have cancer cells.
• The PSA level at the time of diagnosis.
• The Grade Group of your cancer. This is based on the Gleason score, which measures how likely the cancer is to grow and spread.

The staging system is very complex. Below is a summary. Talk to your provider about the stage of your cancer.

Stage I

• (cT1, N0, M0/Grade Group 1 [Gleason score 6 or less]/PSA less than 10): The tumor can’t be seen or felt with an imaging test such as transrectal ultrasound (it was either found during a transurethral resection of the prostate (TURP) or was diagnosed by needle biopsy done for a high PSA) [cT1]. The cancer has not spread to nearby lymph nodes [N0] or anywhere else in the body [M0]. The Grade Group is 1, and the PSA level is less than 10, OR
• (cT2a, N0, M0/Grade Group 1 [Gleason score 6 or less]/PSA less than 10): The tumor can be felt by digital rectal exam or seen with imaging such as transrectal ultrasound and is in one half or less of only one side (left or right) of the prostate [cT2a]. The cancer has not spread to nearby lymph nodes [N0] or anywhere else in the body [M0]. The Grade Group is 1, and the PSA level is less than 10, OR
• pT2, N0, M0/Grade Group 1 [Gleason score 6 or less]/PSA less than 10: The prostate has been removed with surgery, and the tumor was still only in the prostate [pT2]. The cancer has not spread to nearby lymph nodes [N0] or elsewhere in the body [M0]. The Grade Group is 1, and the PSA level is less than 10.

Stage IIA

• (cT2a or pT2, N0, M0/Grade Group 1 [Gleason score 6 or less]/PSA at least 10 but less than 20): The tumor can be felt by digital rectal exam or seen with imaging such as transrectal ultrasound and is in one half or less of only one side (left or right) of the prostate [cT2a]. OR the prostate has been removed with surgery, and the tumor was still only in the prostate [pT2]. The cancer has not spread to nearby lymph nodes [N0] or anywhere else in the body [M0]. The Grade Group is 1. The PSA level is at least 10 but less than 20, OR
• (cT2b or cT2c, N0, M0/Grade Group 1 [Gleason score 6 or less]/PSA less than 20): The tumor can be felt by digital rectal exam or seen with imaging such as transrectal ultrasound. It is in more than half of one side of the prostate [cT2b] or it is in both sides of the prostate [cT2c]. The cancer has not spread to nearby lymph nodes [N0] or anywhere else in the body [M0]. The Grade Group is 1. The PSA level is less than 20.

Stage IIB

• (T1 or T2, N0, M0/Grade Group 2 [Gleason score 3+4=7]/PSA less than 20): The cancer hasn’t spread outside the prostate. It might (or might not) be felt by digital rectal exam or seen with imaging such as transrectal ultrasound [T1 or T2]. The cancer has not spread to nearby lymph nodes [N0] or anywhere else in the body [M0]. The Grade Group is 2. The PSA level is less than 20.

Stage IIC

• (T1 or T2, N0, M0/Grade Group 3 or 4 [Gleason score 4+3=7 or 8]/PSA less than 20): The cancer has not yet spread outside the prostate. It might (or might not) be felt by digital rectal exam or seen with imaging such as transrectal ultrasound [T1 or T2]. The cancer has not spread to nearby lymph nodes [N0] or elsewhere in the body [M0]. The Grade Group is 3 or 4. The PSA level is less than 20.

Stage IIIA

• (T1 or T2, N0, M0/Grade Group 1 to 4 [Gleason score 8 or less]/PSA at least 20): The cancer hasn’t spread outside the prostate. It might (or might not) be felt by digital rectal exam or seen with imaging such as transrectal ultrasound [T1 or T2]. The cancer has not spread to nearby lymph nodes [N0] or anywhere else in the body [M0]. The Grade Group is 1 to 4. The PSA level is at least 20.

Stage IIIB

• (T3 or T4, N0, M0/Grade Group 1 to 4 [Gleason score 8 or less]/Any PSA): The cancer has grown outside the prostate and might have spread to the seminal vesicles [T3], or it has spread into other tissues next to the prostate, such as the urethral sphincter, rectum, bladder, and/or the wall of the pelvis [T4]. It has not spread to nearby lymph nodes [N0] or anywhere else in the body [M0]. The Grade Group is 1 to 4, and the PSA can be any value.

Stage IIIC

• (Any T, N0, M0/Grade Group 5 [Gleason score 9 or 10]/Any PSA): The cancer might or might not be growing outside the prostate and into nearby tissues [any T]. It has not spread to nearby lymph nodes [N0] or anywhere else in the body [M0]. The Grade Group is 5. The PSA can be any value.

Stage IVA

• (Any T, N1, M0/Any Grade Group/Any PSA): The tumor might or might not be growing into tissues near the prostate [any T]. The cancer has spread to nearby lymph nodes [N1] but has not spread anywhere else in the body [M0]. The Grade Group can be any value, and the PSA can be any value.

Stage IVB

• (Any T, any N, M1/Any Grade Group/Any PSA): The cancer might or might not be growing into tissues near the prostate [any T] and might or might not have spread to nearby lymph nodes [any N]. It has spread to other parts of the body, such as distant lymph nodes, bones, or other organs [M1]. The Grade Group can be any value, and the PSA can be any value.

How is prostate cancer treated?

Treatment for prostate cancer depends on many things, like your cancer stage, age, overall health, and testing results. Your treatment may include some or all of the following:

• Watchful waiting and active surveillance.
• Surgery.
• Radiation Therapy.
• Hormone Deprivation Therapy.
• Cryotherapy.
• Chemotherapy.
• Immunotherapy.
• Targeted Therapy.
• Clinical Trials.

Watchful waiting and Active surveillance

Watchful waiting (also called observation) is sometimes used when the patient is older or has other health problems where treatment may not be good for them. Watchful waiting uses fewer tests and the patient’s symptoms guide treatment. This treatment is most often meant to control symptoms from the cancer, but not to cure it.

Active surveillance watches the cancer closely. You will often need to see your provider for a prostate-specific antigen (PSA) blood test about every 6 months and a digital rectal exam (DRE) at least once a year. Prostate biopsies and imaging tests may be done every 1 to 3 years as well. If your test results change, your provider will go over treatment options.

Surgery

Surgery is the most common treatment for prostate cancer if it has not spread outside of the prostate gland. The main surgery used to treat prostate cancer is called a radical prostatectomy. There are a few ways to do this surgery. Read about the different kinds of prostatectomy at OncoLink.org.

Radiation Therapy

Prostate cancer is often treated with radiation therapy. External or internal radiation therapy may be used.

External radiation therapy uses high energy rays (similar to x-rays) to kill cancer cells. The rays enter the body, are directed at the cancer, and come out the other side of your body. The types of external radiation that can be used are three-dimensional conformal radiation therapy (3D-CRT), intensity modulated radiation therapy (IMRT), and stereotactic body radiation therapy (SBRT).

Another type of external beam radiation is proton therapy. Proton therapy deposits most of its cell-killing energy within the tumor site (the prostate gland). This helps to protect nearby tissues from the effects of radiation.

Brachytherapy is the use of internal radiation. Small radioactive seeds are implanted into the patient's prostate in the operating room. The seeds slowly put out radiation to kill cancer cells. There is the possibility that the seeds will move out of your prostate. You may need to stay in the hospital for a few days after the treatment is done.

Radiation therapy, like most treatments, can cause side effects. These can be short-term or late effects. Short-term side effects can happen during or shortly after radiation treatment. Late effects can happen months to years after radiation treatment.

Hormone Deprivation Therapy

Prostate tissue and prostate cancers depend on male sex hormones, called androgens, to grow and replicate. Testosterone is an androgen that is very important to the prostate gland. Men make androgens in their testicles. One of the ways to treat prostate cancer is to remove androgens from the body, making the cancer shrink and grow more slowly. This is called androgen deprivation therapy (ADT). There are a few different ways to remove androgens:

• Orchiectomy: Removal of a man's testicles.
• Medications:
  • LHRH agonists: Block the production of androgens.
  • Anti-androgens: Block androgen receptors.
  • Estrogen/DES.

The choice of which ADT to use is based on the extent of the disease and if it is given with radiation (concurrent) or before radiation (neo-adjuvant). Sometimes, a combination of methods is used.

After a while, all prostate cancers will become resistant to hormonal therapy. However, this often takes many years.

There are a number of side effects associated with hormonal therapy. Hormonal therapy will almost always cause impotence and the loss of your sex drive. It can also cause breast enlargement, hot flashes, and muscle and bone loss (osteoporosis). There are some things your providers can prescribe to help with bone loss and hot flashes, but little can be done about loss of libido and impotence.

Cryotherapy

Cryotherapy uses very cold temperatures to “freeze” prostate tissue and kill cancer cells. It is also called cryosurgery. Cryotherapy can be done to the entire prostate gland or to certain areas (called focal cryotherapy).

Chemotherapy

Chemotherapy is the use of anti-cancer medications to kill cancer cells. There are a number of chemotherapy drugs that can be used for prostate cancer, and they are often used in combinations. Common medications used in the treatment of prostate cancer are docetaxel and cabazitaxel in combination with corticosteroids (prednisone). Metastatic prostate cancer may be treated with additional therapies including abiraterone, enzalutamide and mitoxantrone.

Immunotherapy

Immunotherapy is the use of a person's own immune system to kill cancer cells. Examples of immunotherapy medications that may be used to treat prostate cancer are sipuleucel-T and pembrolizumab

Targeted Therapy

Some cases of prostate cancer may be treated with targeted therapies that focus on certain gene changes or proteins in the tumor. Targeted therapies work by targeting something specific to a cancer cell, which lets the medication kill cancer cells and have less of an effect on healthy cells. Examples of targeted therapies for prostate cancer are rucaparib and olaparib. Both of these medications work when there is a mutation in either your BRCA1 or BRCA2 gene. Your provider will test you for this mutation before treatment with these medications.

Clinical Trials

You may be offered a clinical trial as part of your treatment plan. To find out more about current clinical trials, visit the OncoLink Clinical Trials Matching Service.

Making Treatment Decisions

Your care team will make sure you are included in choosing your treatment plan. This can be overwhelming as you may be given a few options to choose from. It feels like an emergency, but you can take a few weeks to meet with different providers and think about your options.

To learn more about prostate cancer, read more at OncoLink.org.