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This is an excellent analysis from a cohort of patients who were diagnosed with prostate cancer in the United Kingdom from 1999 to 2009. There are several caveats to glean from this article.
This was a monitoring of 2,664 men diagnosed with prostate cancer, found during a national screening program using PSA blood testing for screening.
82,429 men were screened every other year. Ages screened were 50-69 years. Over 10 years, three percent of the screened group were diagnosed with prostate cancer. Data was collected over 10 years, so on average, a 0.3% per year testing yield was found. This shows very few people screened had/developed cancer.
At the time of this study the standard of care was to offer surgical resection of the prostate or localized radiation of the prostate tissue and surrounding area (radiotherapy). Depending upon staging of disease, sometimes additional hormone blockade therapy was given up front in addition to the two primary active treatments.
The question this study addresses is "what if we just monitor this problem and adapt our treatment plan depending upon whether there is evidence of this cancer progressing or not"?
In the monitored group, if the cancer progresses, then one can choose to consider prostatectomy or radiotherapy OR chemical therapy. Chemical therapy can include hormone blockade (a standard of care for recurrent or high tumor burden disease) or chemotherapy. Since the initial date of this study, several new chemotherapy options have been made available.
The study design took the 2,664 prostate cancer positive cases. They were randomized equally to an intention-to-treat grouping. The three groupings were one of three options.
1) Observation with surveillance/monitoring.
2) Prostatectomy (prostate resection)or
3) Radiotherapy to the prostate.
An intention-to-treat analysis is a good method to look at treatment comparisons as it reflects a real world scenario of choosing an initial treatment plan. Further, it allows for treatment adjustments or changes as the individual case proceeds. This could include: chemical/hormone blockade treatment, additional localized radiation, chemical whole bone radiation. This additional treatment would and could be offered to any of the three intention to treat groups. This is "real life" care management.
There is a lot of meat in this analysis. Click the Read the Actual Study action button to see the entire article.
I wish to point out several bullet points.
- Over 15 years of follow-up, the death rate from prostate cancer wasn't statistically different in any of the treatment plans.
- Collectively, 2.7% (45) deaths from prostate cancer occurred.
- Death from any cause was similar across the board, regardless of initial treatment decision.
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Surprisingly, death from OTHER cancers was the largest cause of death.
- Vascular/respiratory disease was reported as the second leading cause of death in the prostate cancer patients.
- Of all causes of death in the prostate cancer group studied, 51.6% died of "other cancers".
- 31.8% of all deaths were from cardiovascular or respiratory disease. Men are often counseled by their urologists that they will die of vascular disease before prostate cancer. This is true, according to this study data, but actually the highest probability for cause of death appears to be "other cancer" as the real take home message.
- Men diagnosed with prostate cancer have a 97% chance of not dying from this diagnosis, regardless of treatment path chosen.
- Metastatic disease was more likely to be diagnosed in the observation (watchful waiting) group (9.4% over 15 years) vs 4.7% in prostatectomy vs 5% in radiation treatment group.
- Despite the reality of higher metastatic disease with observation, actual death from prostate cancer wasn't statistically different in any initial treatment strategy.
- Our present outcome prediction tools for prostate cancer staging (severity/burden of prostate cancer at diagnosis), DID NOT predict who would do worse over 15 years of follow-up.
- Absolute survival benefit (noting not statistically significant) favored prostatectomy.
- Surprisingly to me, diagnosis at a younger age did not predict a survival disadvantage.
- Intervention at 65 years or older, appeared to benefit the patient over observation compared to the younger than 65 age patients.
- Radiation appeared to result in less death rates in the first decade, but over time (after 12 years), observational monitoring was favored. This suggests radiation treatment has long term complications resulting in treatment associated mortality measurable after 12 years.
- Among the metastatic group, observation as initial intention to treat was more favorable for prostate cancer survival.
Side effects of the intervention arms include: a) for prostatectomy acute death from complications such as pulmonary embolism (blood clot to lungs) or blood pressure collapse (shock) or deep tissue and systemic infection; b)For radiation, there is acute immune stress, non-cancer tissue injury, longer term tissue injury and damage including bladder, prostate and rectal bleeding. Infection is another possible scenario with radiation tissue damage.
Final take home message: The findings indicate that an individual patient needs to factor in the extent of side effects associated with early radical treatments. In new diagnosis of prostate cancer, active initial therapy of prostate resection or radiation to the prostate can result in more harm than good.
Regardless of initial treatment offered, if there is advancing prostate cancer seen during monitoring, chemical treatment options are available and effective. This long term treatment study demonstrates that holding these chemical options back for advancing disease resulted in no compromise in survival from prostate cancer.
For me as your doctor, given the favorable long term prognosis from the diagnosis of prostate cancer, this data reinforces the concept of testing PSA levels less frequently. Time appears not of the essence in detecting this disease. Further, having prostate cancer appears to be a marker for higher risk of other cancers and mortality from missing this fact. That is the real meat. Being diagnosed with prostate cancer indicates you are likely to die of a different cancer with a higher probability than even vascular or respiratory disease. That folks is a paradigm shift in thinking.
Noting this new information, I would point out that cancer is a deregulation of normal cellular replication. The combination of genetic inheritance AND environmental unknowns,appear to result in overall/general cancer risk. If you have prostate cancer (or any cancer for that matter), you should widen your cancer screening considerations.
I wish to remind my patients there is a new technology for cancer detection that involves a simple blood test. This test is known as the Galleri cancer "blood biopsy" test.
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