Update as of 2 August: the papers summarised below (and a number of others) are available on the PCFA site as videos . In order to view this content you may need to be logged into the site; if so, however, there is no charge for this.
Updates as of 3 July:
- I forgot to say, I won a door prize! First time ever. (A nice tea set.)
- Interesting article in The Age today about exercise. This article repeats many of the observations from the exercise paper summarised below.
I went to a Community Conversation at the new Peter MacCallum Cancer Centre in Kensington a few months ago. This was an event organised by the Prostate Cancer Foundation of Australia, an organization that I have linked on my Resources page. (PCFA is the peak national body for prostate cancer in Australia. They also organize the Survivors’ Groups, publish a web site with discussion boards, present webcasts, and much more besides. ) This event gave cancer patients like me, their carers, and anyone interested the chance to find out about recent research into prostate cancer.
The presentations from this day were to be made available on the PCFA web site, but this seems not to have happened yet. I will see what is the state of play and update this entry if there is any new information. Meanwhile, this is my summary of a few sessions. (What follows is based on the notes I took on the day, and doesn’t represent PCFA or other organisational policy! Responsibility for any errors in what follows is entirely mine. ) Any content in square brackets is one of three things:
- to do with the formatting or layout of this blog entry;
- my gloss on what was said; or
- related material that wasn’t mentioned on the day.
The Welcome, presented by Jim Hughes, National Chairman, PCFA, made some interesting points:
- prostate cancer (I will refer to it as PCa from now on) is responsible for about 3,000 deaths each year. Among Australian cancers, it is the second biggest killer of men after lung cancer.
- a TheraP trial is currently being undertaken as a partnership between PCFA and ANZUP Cancer Trials Group.
- there are now about 45 specialist PC nurses available through the health system. Men interested can ask their GP about this. This is obviously a great step forward in being able to give PCa patients continuing care while they are in between consultations with their specialist and GP.
The changing treatment landscape of prostate cancer in Australia (Dr Ben Tran)
This presentation gave an overview of what treatment was appropriate for what type of PCa. For the purposes of this presentation there are three main types of cancer; local (i.e. localised), castrate naive, and castration resistant. [This jargon is unpacked underneath the “ADT” sub-heading below.]
The following table attributes the main treatment options to each type. [Apologies if the tables are formatting rather weirdly; I had to paste them in from Google Docs, my MSOffice subscription having expired.]
|ADT (androgen deprivation therapy):
|Watchful waiting/active surveillance||Radiotherapy|
ADT can be combined with radiotherapy. [Coincidentally, I read a paper just recently that looked at the outcomes for different PCa patients of this combination. See the recent post on the PCFA research blog. This link may not open unless you are a member of PCFA and are logged in.]
Robotic versus traditional methods of surgery (i.e. for prostatectomy) were discussed briefly. There doesn’t seem much difference between these in terms of outcomes.
It is known that androgen feeds PCa. ADT therefore seeks to reduce the levels of androgen/testosterone to a castration level. (There was some discussion in the Q&A segment about whether medicos could use a word other than “castration” to describe this treatment; it was felt that this word was pretty off-putting. Dr Tran acknowledged this, but doubted that there was another word that could accurately describe the effect of the treatment.)
Side effects of ADT were equivalent to a male menopause: fatigue, hot flushes, arterial stiffness, and osteoporosis. [These will not necessarily all be experienced, but are on the cards.] Exercise is a great way to deal with these side effects:
- it can be started and stopped at will
- it has a medium term benefit for quality of life
- it has no impact on survival outcomes.
[For much more about exercise, see also Dr Neumann’s paper below.]
PCa can make one’s own testosterone resistant to ADT. [This is the “castrate resistant” mentioned above. Where this has not happened, PCa is referred to as “castrate naive”.]
This table lists what treatments are appropriate to each cancer type:
Chemotherapy (CT) for PCa is less severe than for other types of cancer. Initial CT can improve the effectiveness of ADT. It appears to do this by inhibiting the cancer’s dividing process.
Bone secondaries, where they occur, can be treated with zoledronic acid.
The main question is how best to combine the various treatments for each patient. There is a number of approaches under investigation:
- Genetic. For example, the genetic marker known as AR-V7 could be predictive of lower rates of success with abiraterone and/or enzalutamide. PARP inhibitors are recruited by PCa to repair errors in its replication. [I came across a good article on the Cancer Research UK web site about these.]
- Immunotherapy uses the body’s immune system to fight the cancer. However, to date, results have generally not lived up to the promise. Perhaps they need to be combined with a higher dose of radiation?
- Theranostics “… uses specific biological pathways in the human body, to acquire diagnostic images and also to deliver a therapeutic dose of radiation to the patient. A specific diagnostic test shows a particular molecular target on a tumour, allowing a therapy agent to specifically target that receptor on the tumour, rather than more broadly the disease and location it presents” [description taken from Theranostics Australia’s web site]. An example is the recent trial of Lu-PSMA or Lutetium-177. The TheraP trial seeks to compare the effectiveness of this treatment with that of CT. (About 50% of subjects had lower PSA readings.)
DNA sequencing (Dr Niall Corcoran)
DNA is found in cell nuclei. Cancer is a disease of DNA, featuring
- uncontrolled cell growth
- resistance to cell death (the process that normally leads to most of our cells being replaced after several years)
- the ability to invade and spread to other sites.
The cost of DNA sequencing has dropped enormously. In 2001, the first DNA sequence cost $15 billion dollars. A sequence now can be done in two days and cost $4,000 for a tumour.
Projects in current DNA-related research include investigation of
- the link between genomics changes and clinical outcomes
- drivers of metastases
- risk stratification TP53 assay treatment resistance (the ADEPT trial).
There was a couple of interesting questions:
Q1. What about men with sudden increase in PSA levels?
A1. There is a PSA risk continuum. 25% of men with normal DNA have or have had PCa. PSA is continuously variable in the same way that height is [i.e. there is a small number of men with very high and very low PSA, and a large number with scores falling in between these extremes]. The normal/abnormal threshold needs to be specified. If the threshold is set at a low level, more cancers will be caught, but more unnecessary surgery will be performed. PSA levels will vary naturally with age, so thresholds need to be age-specific. Combining PSA with adjunct tests will give improved predictive ability. Some of the worst cancers occur in men with low PSA levels (around 2-3%). The digital rectal examination is still important.
Q2. Are there different types of PCa?
A2. Yes. Seven different molecular types have been identified. However, the differences between them are not well understood.
Exercise (Dr Patricia Neumann)
Exercise can benefit the quality of life (QOL) and muscular/aerobic fitness of PCa patients, and cause very few side effects. Some specific advantages: a reduction by
- 33% in Alzheimer’s risk
- 61% in PCa risk.
Looking again at PCa, there is
- a reduction in fatigue
- an increase in QOL
- a reduction in distress, stress and depression.
50% of adults in Australia are not active enough. Why is this?
- Doctors don’t learn about it in medical school
- there isn’t a drug company behind it to promote it, so doctors are less likely to recommend it, unless they exercise themselves; but
- they exercise less than the general population.
What are the weekly guidelines?
- Cardio; either
- vigorous intensity , 20 minutes in duration, twice a week; or
- moderate intensity, 30 minutes in duration, five times a week; and
- Strength training; between 8-12 reps, twice a week.
- This can be done either with weights or resistance bands.
Three hours of exercise a week sounds a lot, but leads to a 49% reduction in death from all causes.
For PCa patients having ADT in particular, exercise is associated with
- an increase in vitality
- reduced fatigue
- reduced bone loss and fracture risk
- reduced muscle mass loss
- increased strength.
There was a great Q&A for this session. The most memorable part was relating to mobilization of pelvic floor muscles. [This is an important part of regaining urinary continence post-prostatectomy.] A guy asked Dr Neumann’s opinion of a phrase he had heard, intended to assist with finding the darn things in the first place. This advice was “Suck your nuts up to your guts”. (Most of the, predominantly male, audience found this hilarious.)
Dr Neumann’s answer involved standing everyone up and getting them to feel for their pubic bone in the front and sitting-bone at the back. The PFMs run between these points. I can therefore accurately describe this as a hands-on session. (The MC, Julie McCrossin, formerly of Radio National, said it was the best Q&A session she had ever heard.)