Prostate Cancer Prognosis
Patients with smaller, slow-growing, well-differentiated tumors tend to have the best prognosis with prostate cancer. Whether someone is alive and disease-free 10 or 15 years after diagnosis tends to depend more on the stage and grade of the cancer than on the choice of treatment. If cancer is limited to the prostate and is well or moderately differentiated, the 5-year prognosis is considered excellent.
Prostate Cancer Prognosis: An Overview
Your chances of being alive, and disease-free, 10 or 15 years after a prostate cancer diagnosis are apt to depend more on your stage and grade of cancer than on the choice of prostate cancer treatment.
The best prostate cancer prognosis, as might be expected, is for patients with smaller, slow-growing, well-differentiated tumors. The good news is that approximately three-quarters of all newly diagnosed prostate cancers are clinically localized (stage I or stage II). About 15 percent are stage III, and 11 percent are stage IV.
Prognosis for Stage I and Stage II Prostate Cancer
If your prostate cancer is limited to the prostate (stages I or II) and it is well or moderately differentiated (Gleason score 7 or below), the 5-year outcome is considered excellent for all three treatment options:
- Watchful waiting
- Radiation therapy.
Even at the end of 10 years, few men with stage I or II and a low Gleason score will have succumbed to prostate cancer.
With a median age of 72 at diagnosis, many men with prostate cancer die of a variety of other natural causes in the next 10 to 15 years. Few men with low-grade localized disease die of prostate cancer. The disease-specific survival rate -- which excludes deaths from other causes -- is close to 90 percent. In other words, regardless of treatment -- watchful waiting, surgery, or radiation therapy -- such a man can consider his cancer a chronic disease because he is much more likely to die of other causes than of prostate cancer.
Men with localized tumors who opt for watchful waiting, if they live long enough, may run a greater risk of eventually developing metastatic disease. In one series of studies, the chance of developing metastases within 10 years was 19 percent for men with well-differentiated tumors and 42 percent for men with moderately differentiated tumors.
Only one small study has directly compared watchful waiting with radical prostatectomy, and it found no significant differences in survival.
Surgery or radiation therapy is typically chosen by those men whose tumors, although apparently localized, are more extensive or poorly differentiated (Gleason score of 8 to 10). Without aggressive therapy, around three-quarters of such men will have developed metastatic disease in the following 10 years, and two-thirds will have died from prostate cancer. Whether or not treatment can change these outcomes is under study.
The reality is that not all seemingly localized cancers are, in fact, limited to the prostate gland. When examining excised biopsy tissue, pathologists find that as many as half show prostate cancer that has broken through the capsule, invaded the seminal vesicles, or spread into the surgical margins or lymph nodes. In other words, many cancers that are clinically stage I or stage II need to be reclassified as stage III after the pathologist reports his or her findings.
In other cases, even some cancers that are clinically staged and pathologically verified as stage I or II apparently are still capable of spreading, since up to one-fourth of these patients will experience the recurrence of prostate cancer over the next few years. A review of Medicare records from around the country found that more than one-third of the men initially treated with radical prostatectomy needed additional cancer treatment in the next 5 years.