When one speaks of localized, low-risk prostate cancer, one immediately clashes against two great problems: the first one, whether to perform screening to search it; the second one, whether to intervene immediately or not. In order to clear up at least the second point, an observational trial has been performed using a Swedish national database. The medical records of 6849 males ≥ 70 years of age, affected by localized prostate cancer have been examined: almost all cancers had been diagnosed after PSA determination. According to the values of this test and to Gleason score, 39% of these cancers had been classified as “low-risk cancers”, while the remaining 61% as moderate-risk cancers. Most subjects underwent immediate treatment (prostatectomy or radiotherapy), while 1/3 of them was simply followed through the so-called “watchful waiting”. Among low-risk patients, specific mortality at 10 years has been of 2.4% in the group undergoing watchful waiting and of 0.7% in the group undergoing immediate intervention. In the moderate-risk group, these values have been respectively of 5.2% and 3.5%. During the 8-year follow-up, one third of patients in the watchful waiting group has undergone surgery, radiotherapy or chemotherapy. As we would have expected, the overall mortality has been significantly higher in the watchful waiting group, since in this group almost all older patients with important comorbilities have been enrolled.
A simple watchful waiting in patients with localized prostate cancer to be classified as having a “low risk” implies a low specific mortality, in spite of the selection bias that this observational trial has implied. Results meet the ones from a similar American trial published in 2009, where mortality resulted slightly higher but the participants’ average age was higher (78 years of age).
