By David Most, PhD

Reading Between the Lines is devoted to reviewing  and questioning some of the press releases from medical researchers and institutions.   We  look at the claimed results, comment on their logic, and  note ift we see poor statistics, exaggerated claims, and  who we think might benefit from the story.??We’re concerned that too much of  modern medicine is practiced by "Press Release" and  NOT  ENOUGH  by good science!

So here we go...............if you have any questions contact us directly for a prompt reply This e-mail address is being protected from spambots. You need JavaScript enabled to view it

 

Pomegranate juice and recurrent CaP...a recent study in the Molecular Cancer Therapy jjournal, with human subjects, showed that PJ could significantly lengthen the PSA doubling time for men who were experiencing recurrence of disease following primary tx.

The article reported that in some cases, PSA doubling time was extended from 15 months to 54 months.  This is a substantial effect supporting some of the anti-cancer properties of pomegranate juice.  Let's see if more good news like this begins to appear in the literature.

 

More on Screening vs Non-screening Impact on Overall Mortality and Cancer Specific Mortality...A recently electronic publication  (Oct 7, 2009) compared overall mortality and cancer specific mortality in two populations: 10,000 screened men vs a similar group who were't screened.  This work comes out of the recent study in Europe that showed a survival benefit in favor of the screened group.  In this sub-analysis, the authors reported that 34% of CaP deaths were in the non- screened group, vs 13% of deaths from CaP in the screened group.  The difference in cancer-specific mortality was 0.8% (non-screened) vs. 0.3% in the screened group.  Since there were only 39 deaths from CaP in this study, the broad applicability of the stats is questionable.  However, the results are consistent with the initial findings of this European study several months ago that found survival advantages among the screened participants compared to the non-screened.

This debate is currently raging in the literature.  The ACS has come down with the camp that says screening is not accomplishing any benefit in overall survival.  The American Urological Association and others are still arguing strongly in favor of screening to detect early CaP and thus increase overall survival.

BETWEEN THE LINES will report more on this debate as newer positions emerge.

[Editor's Comment: Perhaps mass screenings are not useful in saving lives, but giving a man the information about whether he, as an individual,  does or does not have CaP, certainly provides a better basis for  intelligent decision making.  We would argue that death from CaP is not a pleasant experience.  Is there a valid trade-off between the risk of some morbidity from over-treatment versus removing a potential life-threatening cancer?

WHEN DOES 4+3 NOT EQUAL 3+4?....Answer: when one is dealing with Gleason Score and the difference can mean aggressive tumor vs less aggressive tumor!  3+4 means that the pathologist is seeing an imbalance in favor of the less aggressive Grade 3 tumor vs the more aggressive Grade 4 variety.  It is an eyeball measurement that hasn't changed appreciably since Dr. Gleason first suggested the scoring system many years ago.  For those tumors rated as 4+3, the pathologist is reporting a preponderance of grade 4 tumor with a lesser proportion of Grade 3.  Not as good for the pt. as the 3+4 combination.  A recent paper J Urol 2009 Oct 15 presented some clinical results from the Fred Hutchinson Cancer Center in Seattle.

Their study was based on a population of 753 men followed for a median of 13 years.  65 deaths from CaP occurred.  The authors reported that of those 65 deaths, the disease specific survivals were: 92% for 3+4 scores, 76% for 4+3 scores and 70% for 8-10 Gleasons.  A look at the confidence intervals for these averages shows a very wide range which is not unusual.  CaP is most difficult to generalize about.  What is poor in one man can be quite different in another.  But with these limited data, the point is made.  The lower the Gleason score (especially of 6 or less), the better one's survival chances are and the more likely he is to respond favorablu to whichever treatment mode is chosen.

TAKE HOME LESSON: Gleason scores, although based on an eyeball technique developed in the 70's by Dr. W. Gleason, are still very useful in sorting prostate cancers from the least to the most aggressive variety.  Perhaps one day somebody will figure out how to automate the idea to eliminate the inter-lab variabiliy that still occurs.

The Prostate Cancer Foundation discusses Proton Beam Therapy. August, 2009....
The Prostate Cancer Foundation has just published a review article discussing Proton Beam Therapy (PBT) for prostate cancer.  Given the push for reductions in health care costs, this is a timely review.  Proton Beam instillations are extremely expensive ranging up to $150-million.  For  this technology to  be economically feasible, the provider has to treat a large number of prostate cancer cases monthly.  It is a Medicare reimbursable expense but not 100%.  Given the several other radiation modalities that offer good results , justifying PBT treatment can be a challenge.
PBT principal advantages are reduced energy to tissue at the point of beam entry and then the theoretical deposit of all remaining energy in a very specific targeted volume.  This is called the Bragg Peak and would be the ultimate justification for this treatment method. .  But as in all things radiological, between the reality and the theory falls the shadow!There is energy hitting tissues behind the target  (reaching the rectum and fossa) and this radiation can and does produce  side effects similar to all other types of radiation. 

Recently,  ICER (Institute for Clinical and Effectiveness Review) of  Massachusetts General Hospital completed a study in which it compared brachytherapy, IMRT and proton beam for prostate cancer  treatment.

ICER  concluded that the best overall treatment, including cost, was brachytherapy. Then came IMRT.  The heavy capital investment needed to create a PBT facility adds a heavy cost burden to PBT procedures.

Work is currently going on to produce proton particle accelerators that would cost considerably less than present generation cyclotrons.  Such new designs are projected to be in the range of  $25 million.  That's a  lot less than the recent University of Florida installation in Jacksonville that  reportedly cost about $140 million.

The debate continues, so stay tuned.  If you are considering  PBT for your own  prostate cancer treatment, , check your insurance company's attitude towards it.   Child tumors have been and are being treated very effectively with PBT.  Prostate cancer can be radiologically treated using other, lower cost radiation devices.

 

TAKE-AWAY MESSAGE: PBT IS AN EFFECTIVE SYSTEM BUT COSTS ARE TOO GREAT.  EQUAL RESULTS ARE OBTAINABLE WITH LESS COSTLY RADIOTHERAPY METHODS.

If primary Prostate Cancer treatment fails,  what’s the salvage potential?.-ASCO April, 2009....

At the April 2009  ASCO (Americn Society Clinical Oncology)) meeting in Orlando, FL a paper was presented by a group from the Japanese Kitasato University School of Medicine and Duke University.  It was an in-depth review of the literature searching for all published material dealing with how to treat recurrent prostate cancer if the primary radiation therapy didn't work.  What options does a man have and how can he weight them?

Except for hormonal blockade therapy, i.e., Lupron or Zoladex or their ilk, all other options involve some kind of tissue ablation treatment.  And of these, the list grows longer almost daily!  If surgery of any kind (open, laparoscopic, or robot- assisted laparoscopic) fails to eliminate 100% of the tumor cells, the patient will be offered a menu consisting of:
1.    Salvage Surgery
2.    Cryosurgery
3.    High Intensity Focused Ultra Sound (not yet FDA approved)
4.    Salvage Brachytherapy

Being left with a "cooked gland" that may still contain viable prostate cancer cells, these so-called salvage treatments vary in their potential for adding to the side effect burden of the patient.  He may already have a damaged rectal wall,  an irritated bladder neck, or other Quality of Life (QOL)reducing complications from the primary radiation. Now he must choose the lesser evil among the options left.  It is safe to say that of all of the salvage options open to him, none is likely to be effective in ridding the gland of remaining cancerous tissue.  And we haven't even addressed the issue of cancer that has spread beyond the gland!  Only hormonal blockade therapy can effectively deal with this kind of disease.

 

TAKE-AWAY MESSAGE:  DO EVERYTHING IN YOUR POWER TO AVOID HAVING TO DEAL WITH RECURRENT CaP.  SALVAGE THERAPY CARRIES TOO MANY POTENTIALLY NEGATIVE CONSEQUENCES.

Stereotactic Body Radiotherapy: An Emeging Treatment Approach for Localized Prostate Cancer..... this is a recent online  publication , Technology in Cancer Research and Treatments, October 2009.  It was written by several MD's who operate a Cyberknife Center and Radiation Centers in th Tampa Bay area of Florida.

 

This article describes results for a series of 5 treatments with the Cyberknife at a dosage of 5 gray per session, or a total of 35 Gray.  A claimed advantage of the Cyberknife is a significant reduction in the total radiation dosage compared to modalities such as EBRT,  IMRT or Conformal Beam radiotherapy.  These usually administer total dosages in the range of 70 to 80 Gray.

Peripheral damage from radiation striking tissues other than the target tissue increases with increasing dosage.  The Cyberknife offers a highly focused energy beam plus a robotic control system that makes the beam track the position of the prostate during the period of "beam on".  It is well known that an internal organ like the prostate can vary in position by a centimeter or two, depending on the contents of the bowel, the bladder, gas, etc.

Radiological development has produced systems to track such changes and adjust the radiation beam accordingly.