There are four recognized definitive treatment options currently offered for localized prostate cancer,HIFU, cryoablation, radiation and robotic surgery. The best treatment outcomes after any one of these options is in men that have only truly localized prostate cancer, or cancer localized to the prostate and not outside the prostate. The survival benefits for localized prostate cancer after anyone of these treatment options are similar. However, the complication rates for these four options are quite different and warrant scrutiny.
The majority of prostate cancers are now found in men through screening with the finding of an abnormal total PSA (prostatic specific antigen) and/or %free PSA.
Other than this abnormal blood test, most men are relatively asymptomatic with no findings on digital rectal examination (DRE).
The diagnosis of prostate cancer can ONLY be made through a needle biopsy of the prostate and examining the tissue. The biopsy follows a sextant pattern whereby the prostate is divided into six zones,base, middle, apex of the prostate,right and left and each of those regions is randomly biopsied.
The results of the needle biopsy ( with particular attention to the volume of the prostate cancer in each of these needle biopsy cores and their Gleason score), in addition to the PSA and stage of the prostate cancer, are used in assessing a man’s risk for progression of his cancer. Also, the patient would do well to have the biopsy results validated through an independent reference laboratory to confirm not only the presence of the cancer but the volume and the Gleason score.
In addition to the forgoing, we would factor in a patients age and co-morbidities before suggesting treatment.
The following risk categories are considered:
LOW
PSA less or equal to 10ng/ml
Gleason score less or equal to 6
Stage T1,T1c,T2a
the risk is higher if greater than 50% of the cores are positive
INTERMEDIATE
PSA between 10 and 20ng/ml
Gleason score 7 (risk is greater for 4+3 compared to 3+4)
Stage T2b, T3a
the risk is higher if greater than 50% of the cores are positive
HIGH
PSA greater than 20ng/ml
Gleason score 8-10
Stage T3b
Of these three RISK CATEGORIES, the majority of LOCALIZED prostate cancers are found in the LOW to INTERMEDIATE RISK GROUPS.
How then can we assess the patients further (other than with imaging studies such as bone scans,CT and MRI scans) so we can prevent men from having treatment for presumed localized disease when the cancer may not be localized and already outside the prostate. The best method is to biopsy the MARGINS or the limits/edges of the prostate. If these margins are clear we can be fairly confidant that the prostate cancer is indeed localized and treatment would be ideal with a minimally invasive option such as HIFU.
MARGINS
After return of the validated biopsy report, I will look at where the cancer was found in the prostate, the tumor volume and the Gleason score. If there is significant cancer volume at the base (close to the bladder/seminal vesicles) or apex (close to the urinary sphincter) of the prostate or there is a Gleason score 7 or higher in these areas, I will have the patient undergo a biopsy of the MARGINS of his prostate. This may mean an additional biopsy but the importance of this step is outweighed by the possibility of preventing a man from having a treatment that may not be in his best interests. It is pointless subjecting a man to a treatment option that is ideal for LOCALIZED prostate cancer when the cancer is not really localized. For example, in addition to the considerable risks associated with debilitating surgery ( including robotic prostatectomy) with incontinence and impotence, 20-40% of the men treated in this manner will have positive margins (or cancer left behind) necessitating the need for additional treatments such as radiation.
Should biopsies of the prostatic margins show cancer infiltration and therefor a cancer no longer localized to the prostate, the patient is probably better served by radiation. Although radiation is associated with an increased risk for longterm bowel and bladder dysfunction, this treatment option may be a better choice for those men where there is infiltration of cancer at the margins (and particularly in the apical region ) of the prostate as, radiation, by being somewhat imprecise usually also directs treatment outside the confines of the prostate. However,for truly localized prostate cancer disease HIFU appears ideal as it is very precise as well as offering cure with a low risk for longterm complications and not at the expense of quality of life (QoL).