Five or fewer metastases - "durable remission"

[Admin]

I can't seem to find a good account of treatment of five or fewer metastases by using radiation.

I seem to remember a video by Dr Snuffy Myers, but can't locate it.

In the meantime, here are some snippets by Dr Myers.

The key seems to be:

• five or fewer metastases - burn them with radiation
  
• more than five metastases - use ADT to reduce active cancer, using radiation on the last few spots
  
• the radiation to kill off the cancer is higher than the dose normally used for palliation.
  

Well, let us start with the term “cure.” As I talk

with patients, they usually think that this means that

all the cancer is gone. Early in the history of cancer

treatment, physicians realized that they will never

know if the cancer is done as it can hang around in

microscopic dormant clusters (see previous question).

So, in cancer treatment, we count someone

cured when they die of something else without the

cancer recurring. For us, a more meaningful term

may be durable complete remission. This means

there is no evidence of the cancer’s presence and

that this favorable state is continuing for many

years. Using this definition, it is definitely possible

for men with five or fewer bone lesions to enter a

durable complete remission. Some of these men

may well be cured.

Hormonal therapy is the initial treatment of

choice in men with bone metastases. Until recently, it

was the only real option. In 2004, investigators at

University of Rochester looked in detail at the natural

history of men with bone lesions. In those with

five or fewer bone lesions, the cancer would often

stay limited to the initial sites of involvement for

several years before rapidly spreading to new sites.

They proposed that steriotactic radiation to those

sites might prevent subsequent spread. Our experience

since 2004 is that there are indeed men with

limited bone involvement who will benefit from radiation

to bone lesions when the dose is high enough.

So, it would be important to know how many bone

lesions he has and where they are located.

In a patient with a very large tumor in the prostate

and bone metastases, would you consider doing Provenge and immediately follow up with chemotherapy?[/i] in Prostate Forum 13/1']

I am going to presume you are talking about

newly diagnosed metastatic prostate cancer. This is

simple to answer and it would be no. In fact, of the

many approaches available, those would be my last

choices.

Provenge is approved for patients who have

failed hormonal therapy and have metastatic disease

without significant symptoms. So, Provenge would

not likely be paid for in your case and it would cost

you more than $100,000 out of pocket. Also, I am

not aware of any clinical trial evidence that suggests

the therapeutic effectiveness of Provenge in that setting.

Chemotherapy is even easier to dispense with.

Chemotherapy has never been shown to have significant

survival value as an initial treatment and it is

far more toxic than any hormonal therapy program.

The proper approach to your situation would be

to start hormonal therapy. Unless your PSA is

below 10 ng/ml at this point, hormonal therapy is

likely to work for several years. At that point, you

are likely to have much better treatment options

than are now available. This is a very exciting time

in prostate cancer research with an unprecedented

number of new drugs approved or in development.

Here at our clinic, we would likely start you on

Lupron, Casodex, and Avodart. Once your PSA

stopped falling on that combination, we would

replace Casodex with ketoconazole, Leukine, and

transdermal estradiol. In our hands, the latter has an

80% response rate compared with approximately

40% for taxotere chemotherapy.

If you had five or fewer bone metastases, we

would consider radiation to the bone lesions,

prostate gland and pelvic lymph nodes once hormonal

therapy had significantly reduced the size of

the cancer. With this combined approach, we have

some patients who enter a complete remission that

can last for years.

[jm:question]

At age 62 I was diagnosed with a Gleason

4+5=9 prostate cancer. At that time, my PSA was

just above 50 ng/ml and I had 18 bone metastases

on my bone scan. I started on triple hormonal

blockade and by the end of three months, my PSA

had dropped to 0.3 ng/ml. In Prostate Forum

Volume 12 Number 6 on page 7 you write:

“In any case, we do not regard hormonal therapy

as successful unless the PSA drops below 0.01

ng/ml. More recently, we have also asked that bone

metastatic disease and lymph node enlargement

normalize. For example, if at 6 months the PSA is

less than 0.01 ng/ml, but bone metastasis show no

healing, we will consider the switch to second line

hormonal therapy. If the patient has five or fewer

bone metastases, we will consider referring the

patient for radiation therapy to the bone lesions,

but will ask that the dose be 45-50 Gy, not a palliative

dose of 20-30 Gy”.

But how do you diagnose bone metastases that

are not healing (after 6 months triple ADT)? With

5 or fewer bone metastases, you would consider

radiation therapy, but what would you consider in

my case of 18 ? I would like to get rid of these

things…what are the limitations of this focal radiation

treatment? A recent DEXA scan shows normal

bone density.

[jm:Answer]

If the PSA has dropped below 0.01 ng/ml at 6

months, we would repeat the bone scan. If the bone

scan shows healing, we would then study the

involved areas with MRI with and without contrast.

This shows nicely if the bone scan positive areas

are just damaged bone or if there is active cancer.

Our ultimate goal is a normal bone scan and MRI.

At the time that I wrote Beating Prostate

Cancer, we would not have considered radiation

therapy. However, now I evaluate patients more

carefully. Consider the situation where all but three

bone lesions have healed. We know that those

remaining lesions contain the most resistant cancer.

We would then consult with radiation therapy about

the possibility of radiating those persistent lesions,

but with high enough dose to sterilize the lesion.

For high Gleason grade disease, we would often

add PET scan as the PET would detect the most

metabolically active cancer. We would then especially

focus on eliminating that active site or sites.

All of this is pretty new. I can say that this

approach does seem to lead to disease control

durable out to two years. We do not have sufficient

follow up to comment beyond that point. Our basic

strategy is to try for a real durable complete remission

if at all possible.

[Nev Black]

This post "Five or fewer or fewer metastases - durable remission" is very relevant to my particular case which we discussed during the teleconference yesterday, the 25.11.2011. I would like to thank Jim for collecting that information. I also had a call from David A after the teleconference. Jim's post and the talk with David A have confirmed for me that further medical opinions outside the doctors and specialists that I am currently seeing is a necessity. I would like to thank the members of the teleconference for their imput. This is an extremly valuable forum from my perspective. Thank you all.

Nev

[Bruce Kynaston]

With regard to

"The key seems to be:

• five or fewer metastases - burn them with radiation
  
• more than five metastases - use ADT to reduce active cancer, using radiation on the last few spots
  
• the radiation to kill off the cancer is higher than the dose normally used for palliation."
  

I would like to explain that for growth restraining EBRT, one could consider something of the order of 50 Gray units in 4 weeks but if the focus was near the spinal cord, one would not wish to exceed 45 Gy in that time as it would exceed cord tolerance with a risk of paraplegia if the vertebra concerned was below the neck.

For palliation of pain, a lesser dose in fewer doses would be suitable, as it could be repeated later.

(Well, that was my attitude when I practised radiation oncology.)

[Paul Edwards]

There was a paper on oligometastatic (the oligo-prefix comes from the Greek word for “few”) prostate cancer by Drs Myers, Dattoli and Bravo in the February 2012 issue of the PCRI Insights  newsletter: http://www.dattoli.com/publication/PCRI%20INSIGHTS%20Oligometastatic.pdf

 

Dr Farshad Foroudi of the University of Melbourne is currently conducting A pilot Study of patients with Oligometases from Prostate cancer treated with Stereotactic Ablative Radiosurgery (POPSTAR) with a grant from the Prostate Cancer Foundation of Australia.

 

A lay summary of the Study is as follows:

 

“We propose to research a new, non invasive, high-precision radiotherapy technique called "stereotactic ablative body radiosurgery" (SABR) in the context of patients with up to
three tumours that have spread from the prostate to the bone or lymph nodes. At present, these patients have no curative treatment options. SABR is delivered as a single, high dose, precision treatment which is a radical departure from conventional palliative radiotherapy which is delivered daily for one or more weeks.The treatment is convenient for patients, painless to deliver, non-invasive and delivered whilst the patient is fully awake. While SABR has been used in other cancers as well as for prostate cancer confined to the prostate, our trial will be one of the first in patients whose prostate cancer has spread. Most importantly, SABR is potentially curative compared to conventional radiotherapy
to such tumours.”

 

[Paul Edwards]

Dr Faroudi spoke to the monthly teleconference on 23 August 2013 about the POPSTAR trial.

 

There is another clinical trial regarding stereotactic ablative body radiosurgery for oligometastatic cancer about to begin at the Prostate Cancer Research Centre at Epworth Hospital in Melbourne.