A prostate needle biopsy result indicating a 5% or less of a Gleason 6 prostate cancer in one needle core only is termed a micro-focal prostate cancer.
The diagnosis MAY be accurate after a standard 12 core needle biopsy and represent a very small volume of prosta
te cancer BUT it may also represent a mis-diagnosis in either presence or amount of cancer.
First, there is some concern as to whether the diagnosis was made correctly as there is some discordance between pathologists in cancer detection because of subjectivity issues. Second,the biopsy diagnosis may under represent the true status of the man’s prostate cancer. However, the greatest tragedy in the management here would be in treating a man for a non validated assumed microscopic focus of prostate cancer when he did not really have it, or, to treat a minuscule amount of prostate cancer that had little risk of progression.
The monitoring of a man with an initial validated micro-focal prostate cancer can be somewhat involved as monitoring for disease progression is not reliable by simply following the PSA, free and percent free PSA or the PCA3. Reliable monitoring can only be done with further biopsies.
In my practice, if a man presents with a validated diagnosis of a micro-focal prostate cancer, I will have him undergo a saturation biopsy under outpatient sedation and taking four cores from each sextant of the prostate (24 cores) 2 – 3 months later.
This process is to ensure that we are not missing the possibility of more significant disease that will require therapy. After my pathologist has delivered his report I will have the biopsy slides submitted to a reference laboratory for another reading and validation of the findings. Ideally, we want this validation undertaken without the benefits of previous reports so that the review is truly independent, blind and not clouded by the opinions of others.
Again,validation is important in the field of prostate pathology as in my experience there can be quite a discordance between pathologists as to not only the amount of cancer present or as to the Gleason score but also as to whether it is even present. This is despite the use of special immuno-histochemistry stains. Also,we have even seen the same pathologist provide a different reading on the same set of slides months later. Of-course,none of this is cause for comfort.
If the validated pathology reading after the saturation biopsy indicates once more the presence of a micro-focal prostate cancer OR no cancer,I will repeat a saturation biopsy 6 – 12 months later. Commonly, however, I cannot confirm the presence of a micro-focal prostate cancer on a saturation biopsy after it having been diagnosed previously. Vanishing cancer?
If the validated reading indicates on the report that there is more significant cancer in terms of tumor volume and or Gleason score, I will review the definitive treatment options of HIFU, cryoablation, radiation and surgery for localized prostate cancer with the patient and his spouse.
Relegating a man to a definitive treatment on the basis of one prostate biopsy suggesting a micro-focus of prostate cancer is clearly premature,potentially harmful and especially questionable as commonly,the existence of a micro-focal prostate cannot be confirmed on a repeat saturation biopsy. Furthermore, those prostate cancer treatment data bases that include patients with non validated T1c micro-focal prostate cancer may have outcome data skewed towards more favorable outcomes than data bases that are much more discerning. Such favorable results are obviously suspect as some of those men diagnosed with micro-focal prostate cancer may never have had the cancer in the first place.
In summary, men and their partners would do well to be very proactive and become informed and empower themselves with knowledge so they can understand their biopsy reports,their treatment options and the associated quality of life (QoL) issues. This knowledge can prevent them from being subjected to over treatment as well as to unnecessary treatment.
There appears to be NO need to rush into a treatment option for even a validated micro-focal prostate cancer as in some men the natural history of this disease is yet to be determined.