Prostate Cancer Prognosis, Survival Rate and ADT
The prognosis of prostate cancer or the probability of relapse following primary therapy depends on the clinical stage of the tumor, Gleason score (histologic grade) and the PSA level before the primary treatment. The other important independent prognostic factors include the pathologic stage of the tumor, invasion of capsule, seminal vesicle involvement, positive surgical margins and lymph node metastases. The prognosis in prostate cancer is poor in :
- clinical stage above T2
- high PSA level at diagnosis
- biopsy Gleason score of 8 to 10
- PSA velocity of more than 2 ng/mL/year
Survival Rate After Prostate Removal and Radiation
Radical prostatectomy can provide cancer-specific survival of 15 years or more in 80% of patients with limited prostate cancer.
- In patients with well differentiated prostate cancers having Gleason scores of 2 to 4, the 10-year PSA progression-free survival is about 70 to 80% with radiation therapy or surgery.
- The 10-year PSA progression-free survival drops to 50 to 70% for Gleason scores of 5 to 7. Eight-year survival for clinically localized tumors with Gleason score less that 7 is 85-95%.
- The 10-year PSA progression-free survival drops further down to 15% to 30% for Gleason scores of 8 to 10 with a 8-year survival rates of about 70%.
- The distant metastasis-free survival response to radiotherapy is influenced by the dose of radiotherapy.
- High-risk patients with Gleason scores of 7 have 8-year survival rates of about 70%, while those with Gleason scores of 8 to 10 have an 8-year survival of about 50% following radiation therapy.
Changes in PSA Levels After Surgery
In patients with rising PSA levels after radical prostatectomy, the important prognostic factors are the :
- pathologic stage
- time taken post-operatively to reach detectable PSA levels
- Gleason score at the time of prostatectomy
- time required for doubling of PSA values
PSA doubling time of 15 months or more are better managed with surveillance. The have median time to metastatic disease in these years is about 8 years and the median survival is about 13 years. Patients with PSA doubling times of less than 3 months are at very high risk of prostate cancer related death and have a median survival of 5 to 6 years.
Prostate Cancer Metastases Prognosis
Major factors in metastatic disease pointing to adverse prognosis at the time of diagnosis include :
- low hemoglobin levels
- elevated alkaline phosphatase (ALP) levels
- poor performance status
Extent of the disease, Gleason score of 8 to 10 and presence of bone pain are other important prognostic factors in metastatic prostate cancer.
- The median progression-free survival in patients with minimal disease (metastatic disease confined to pelvis, spine or nodes) is about 2 years and in extensive disease (metastatic disease affecting viscera, long bones, skull or ribs) about 18 months.
- The median overall survival with androgen deprivation therapy in patients with metastatic disease is 3 to 5 years.
- For men with resistance to androgen the overall survival ranged from 8 months to 20 months depending on the extend of spread.
- In patients with HRPC, higher baseline PSA levels and greater PSA velocity predicts higher-risk for metastatic disease and shorter overall survival.
- Significant rise in the acute-phase reactants is often a finding in the late stages of disease and suggest a poor prognosis.
Palliative (Comfort) Care
Palliative care or comfort care is the treatment undertaken to prevent or reduce the symptoms of a life-threatening illness like cancer. It is usually indicated for cases where other therapeutic options have either failed to “cure” the cancer and the case has advanced to the point where any further treatments aimed at “cure” would be fruitless and drastically reduce the patient’s quality of life. Palliative care is therefore for symptomatic relief.
Bone Pain in Prostate Cancer
Many advanced prostate cancer patients often suffer from bone pain that adversely affect quality of life. The management of pain or other cancer related functional impairment is integral part of palliative care. Palliative management can include analgesics, glucocorticoids, palliative chemotherapy, radioisotopes or radiotherapy.
Radioisotopes (like phosphorus-32, strontium-89) that selectively concentrate in bone lesions are approved for the palliative treatment of painful bone metastases. The treatment is of more value in patients with multiple metastases (cancer spread to several sites). The radioisotopes have been found to reduce the need for opioid painkillers (analgesics) in such patients.
EBRT is effective in painful bone lesions in advanced prostate cancer patients but not an ideal option if there are multiple lesions at different sites. The lesions in multiple sites will progress after EBRT in one site and pain will reappear in a short time afterwards, unless other systemic therapies are initiated to control the disease process. Read more on EBRT under prostate cancer treatments.
Androgen Deprivation Therapy
Androgen deprivation therapy or ADT is the treatment that reduces the androgenic stimulation of prostate cancer cells by different approaches. Androgenic stimulation means the hormonal factors that promote cancer growth.
The various approaches in ADT include :
- Androgen lowering surgery with orchiectomy
- Luteinising hormone releasing hormone (LHRH) agonists
- Anti-androgens
- Steroids like cyproterone acetate
- Non steroids like bicalutamide and flutamide
- Estrogens like diethylstilbesterol
An approach with early ADT or deferring ADT till progression is still debatable and usually depends on the patient preference or often left to the discretion of the attending physician. There is cancer-specific survival benefit with early ADT, but the overall survivals in both approaches have been found to be similar. The cardiovascular risk assessment should also be done before ADT is commenced as ADT is known to increase risk for cardiovascular events.
ADT may be used as neoadjuvant treatment option before definitive primary treatment or used concurrently with it. It may also be used as adjuvant therapeutic agent following radiotherapy or prostatectomy. Patients with recurrence after surgery or radiation may be considered for ADT if they are not suitable for local therapy. ADT may be considered a therapeutic option in patients with high-risk limited disease along in combination with radiotherapy or surgery.
ADT is the standard of care in patients with metastatic prostatic cancer. The options available in advanced cancer include bilateral orchiectomy, LHRH analogues and anti-androgens. The surgical approach in this set up is less preferred by most patients now.
Several LHRH agonists are approved for advanced prostate cancer and are equally effective in reducing the testosterone to castration levels.
The anti-androgens binds to the androgen receptors and blocks its activation by androgens. When anti-androgens are used as monotherapy, there can be increased testosterone levels due to stimulating feedback from the blocked receptors.
Estrogens were found to be associated with serious adverse effects than other LHRH agonists and are now reserved only for secondary hormone therapy.
Last updated on September 11, 2018.