
Physics @ MindSay 
"There is nothing new to be discovered in physics now. All that remains is more and more precise measurement" - Lord Kelvin, ~1900
Ok, I could be mistaken about proton therapy.
Even Lord Kelvin missed a few future possiblities that physicists discovered in the last century, including the very existence of protons (the term was coined by Rutherford, and it first appeared in print in 1920).
Still, I believe that universal proton therapy is premature. The road side of medical technology is littered with "advances" that should have marked progress but didn't. For each type of cancer there may be some (likely small) subset of patients for whom the astonishingly precise measurement of radiation dose and volume can result in incrementally improved cure rates through local control, while still minimizing morbidity. I prefer a few proton facilities equipped with the latest IMPT where carefully selected patients could only be treated as part of clinical trials designed by experts from all disciplines. I would prefer studies designed to objectively measure quality and quantity of life, not surrogates like psa's and imaging shadows. I also prefer world peace.
The technological imperative has once gain prevailed, and the age of proton therapy is upon us. Unintended consequences will occur, though not easily predicted.
The first unintended consequence of proton prolifertion will be an expansion in the total number of patients treated. Because protons are perceived to result in few side effects, a belief among caregivers and patients will be fostered that there is nothing to lose by treatment. If significant morbidity is cut in half but double the number of patients are treated, the total morbidity will be unchanged. Currently proton therapy costs twice as much as photons (at least). Under this set of assumptions costs will quadruple at a time when health care costs in general are exploding.
Quadrupling costs would be justified if survival and quality of life were incrementaly improved. How likely is this to be the case for prostate cancer? About 15% of patients who are diagnosed with prostate cancer die from the disease, and autopsy studies suggest the actual number of prostate cancers is much higher than the 190,000 diagnosed. Natural history studies indicate that a diagnosis of early stage prostate cancer has very little effect on survival ("natural history" means "untreated"), yet these are the cancers most amenable to "cure". But try telling a patient he has "mild" cancer and then advocate watchful waiting. His first question will be: then why did you look for it? His second is likely to be: how can I find a new doctor?
Anatomic stage provides a measure of disease progression. SEER data (crude as it is) based on historic stage shows that 91% of prostate cancer cases are diagnosed while the cancer is still confined to the primary site or after the cancer has spread to regional lymphnodes (localized or regional stage); 5% are diagnosed after the cancer has already metastasized (distant stage) and for the remaining 4% the staging information was unknown. The corresponding 5-year relative survival rates were: 100.0% for localized/regional; 31.9% for distant; and 79.1% for unstaged. Not much room for improvement exists for stage I cancer, at least in terms of survival, and no local treatment will improve survival for those who present with distant spread.
The trick is to find the small subset of intermediate risk prostate cancer patients (perhaps about 15% of the total) who still have local disease at diagnosis but who have a relatively poor prognosis, and then to treat them without vastly expanding the total number of people treated. Since risk stratification has a large element of subjectivity built in, I suspect the latter condition will not prevail.
A second unintended yet inevitible consequence of creating capacity to treat 1600 plus more patients per year (as in the case of th NIU faciltiy) in a market that already has ample radiation treatment capacity will be another escalation in the medical marketing wars. Loma Linda has advertised nationally for years, making claims for protons that push the evidence based envelope.
A roughly fifty year cycle seems to exist for medical hucksterism. In 1850 when the famous gastrophysiologist Wlliam Beaumont recruited a new physician to his private practice in St. Louis he placed a small ad in local newspapers announcing that his new partner had special expertise in diseases of the eye. Beaumont was immediately viciously attacked by colleagues and nearly drummed from the corps of the local medical society.
The then newly created (1849) American Medical Association had borrowed heavily from Thomas Percival's treatise (A Scheme of Professional Conduct Relative to Hospitals and other Medical Charities 1772) on medical "ethics" when it drafted its code of conduct. Advertising was eschewed. By 1900 US newspapers were full of boiler plate ads for patent medicine, medical devices and doctors claiming superior skills or unique services. By 1950 the rules of 1850 had regained the ascendency and physicians were "allowed" only a briefly run "toombstone" in newspapers to simply announce their presence in a community.
By 2000, the advertising cycle was in full upswing again. The "ethical" prescription drug industry (the adjective had been applied to distinguish what has become "big pharma" from the snake oil salesman) went from no ad's aimed at the general public in 1950 to near the top of the spending list by 2000. Last year, Glaxo was the 7th largest spender on ads, spending $2.4 billion, and Johnson & Johnson came in 9th with $2.3 billion in spending, placing the health care giant ahead of Unilever, Toyota and Sony.
Percival's code had been drafted at the behest of a London hospital in an attempt to regulate the relationships between physicians and hospitals and among the physicians themselves. In 2008 individual physicians were largely out of the ad wars. Rather, health care "systems" now "market" themselves with claims that they are either more caring or more skillful (and usually both) than their competitiors.
And so the proton facilities with their $100+ million in bonded indebtedness will advertise for patients. They will compete with each other on a local, regional and national level. It is not accidental that NIU's new facility is across the street from DuPage Airport and its 8000 foot runway, and in the shadow of Fermi Lab's Wilson Hall. (Ironically, Fermi Lab is in a state of decline, having been eclipsed by the more powerful accelerator in Cern.)
NIU has announced that it will enter into an agreement with the Northwestern University Faculty to provide the clinical expertise at its new center. A search of the Northwestern cancer center web site (http://pubs.cancer.northwestern.edu/abstracts/search?do_pagination=1&page=1) for faculty publications containing the word "proton" yielded 59 hits. But none of the 59 papers seem to have anything at all to do with treating patiients with protons. Basically, NIU, which lacks a medical school, will credential and privilege physicians to use its clinical facility. How will NIU judge the compentency of these physicians and what experience with proton therapy will be required? Who at NIU has the clinical experience and expertise to make these decisions? How will prospective patients be informed about these issues? Advertisements?
Check this site to see how the M.D. Anderson Proton Center (for-profit) is to be marketed by M.D. Anderson Cancer Center, which "leased" its name to the center. http://hcrenewal.blogspot.com/2005/10/m-d-anderson-cancer-center-leases-its.html First the marketing agreement to promote the center, then the science to see if it is actually better.
The protonless health care systems will tout their competing services, such as their daVinci robots, brachytherapy, imrt guided photons and expertise in medical oncology. The have-nots will not so gently point out that "to a man who only has a hammer, the whole world looks like a nail" and that proton-only facilities are dominated by mad physicists and unidimensional clinicians. They will do this until they install their own $15 million proton machines. Then they will advertise protons. All this collateral spending will cost many millions.
A third unintended consquence will be to ensure the continued immortality of Will Rogers, who said: "When the Okies left Oklahoma and moved to Califormia, they raised the average intelligence level in both states."
The Will Rogers Phenomenon will occur when both of these conditions are met: The element being moved is below average for its current set. Removing it will, by definition, raise the average of the remaining elements. The element being moved is above the current average of the set it is entering. Adding it to the new set will, by definition, raise the average.
Proton therapy will be declared superior by it's proponents. These proponents will obtain transrectal ultrasounds, transrectal MRI's, CT's, psa's, psa velocity, free psa and other tests to "stage" patients. Historically many of these tests were unavailable or not done in the photon era. More staging most often results in up-staging, which meets the conditions of the Will Rogers Phenomenon.
For example, prostate biopsies from a population-based cohort of 1,858 men diagnosed with prostate cancer from 1990 through 1992 were re-read in 2002 to 2004.The "new" Gleason score readings (high scores indicate poor prognosis) were an average of 0.85 points higher (95% confidence interval [CI], 0.79–0.91; P < .001) than the same slides read in 1990 to 1992. As a result (thanks to Will Rogers), Gleason score-standardized prostate cancer mortality for these men was artifactually improved from 2.08 to 1.50 deaths per 100 person years—a 28% decrease even though overall outcomes were unchanged.
Given the right pathologists and a little staging leeway, most any new treatment will look great. Perhaps surgery looks better than radiation for younger men with prostate cancer (at least according to one widely quoted paper) simply because surgery results in very accurate staging.
For those who prefer more formal cost-effectiveness methodology (like insurance companies), analysis indicates that proton therapy for prostate cancer does not appear to be cost-effective when measured by commonly acceptable parameters, according to a study by researchers from Fox Chase Cancer Center (JCO 2007; 25: 3603-3608). Quality-adjusted survival was similar for both modalities in each age group as measured by QALY: The incremental cost effectiveness ratio was calculated to be $63,578/ QALY for a 70-year-old-man and $55,726/QALY for a 60-year-old man.Quality-adjusted survival was similar for both modalities in each age group as measured by QALY: The incremental cost effectiveness ratio was calculated to be $63,578/QALY for a 70-year-old-man and $55,726/QALY for a 60- year-old man.
"When even the brightest mind in our world has been trained up from childhood in a superstition of any kind, it will never be possible for that mind, in its maturity, to examine sincerely, dispassionately, and conscientiously any evidence or any circumstance which shall seem to cast a doubt upon the validity of that superstition. I doubt if I could do it myself." - Mark Twain
I am a skeptic, in spite of Mark's good advice. The problem is, time will not tell. Prospective randomized trials comparing survival for surgery, brachytherapy, photons and protons for intermediate prognosis prostate cancer patients will not be done. Carbon ion radiation may replace protons, and might be the next half-way technology to usurp the technological imperative. Neither Lewis Thomas nor Thomas Hardy would have been surprised if it happens.
Bourbon Street? Lame. Streetcars that run in the grass? Haven't had the Desire. Cafe au lait and beignets? Don't be (stretch for it.........) du-monde-ing.
Okay, I'm lying. Don't care much for Bourbon Street, but I certainly intend to get to streetcars tomorrow and perhaps Preservation Hall later in the week. My students will be glad to know I graded their papers at Cafe du Monde, and the grades turned out better than usual.
I'm actually here for the American Physical Society March Meeting. The idea is to absorb (broadband, with a peak in the spectrum around the organic superconductors) as much physics as possible.
I overheard a discussion on quantum dots on Canal street during lunchtime today.
- Make hot tea as usual.
- Drink half of it, as you were intending.
- Refill your mug, and place on top of magnet box.
- Refill liquid nitrogen into magnet box, quickly cooling top of box.
- Enjoy a rapidly chilled drink.
As a deliberate creator and a natural scientist, I LOVE, LOVE, LOVE the place where our physical perspective meets our broader perspective! It is the place where I get to map MY OWN set of beliefs. I can plug into all that I already know and mix and match new information to that which both makes sense to me and feels good too...
I have been to the "Perimeter Institute", it has a very fun and allowing bubble of energy about it...as I wandered around and encountered some of the people there I felt quite "at home".
What else would one expect in a playground for the world's most brilliant!? They are there to figure out what makes the Universe tick...
Download the MP3 and give it a listen!! It just aired today - 2007 01 05!
It is geared for a public layman's audience, you'll get caught up on what the latest "accepted theories" of the nature of our reality from our scientific community's perspective.
Perimeter Institute News Release
CBC.ca - Quirks & Quarks MP3
it seems a little bit crampy to behave relly excellent on Mathematics Level2. that's not as easy as i thought them to be. so these days, i buried myself in the library, devoting myself to those books- physics, chemistry, and that difficullt and boring math2.
i am not good at math, in fact, i am so unconfident on math. even though i love physics so so much. but more often than not, i think things in a literal way, not in a formula way. that is not what a physics major student expected to be. i am confused by this these days-whether i should choose physics to be my college year major or not. i have won several awards in physics academic competitions, i also learn the college physics by myself, which of course, except the mathematic part! i really gave a lot of my time and energy to physics during these years. but when it comes to a time to chose an area that i will devote most of my life to, i became unsure and careful.
i ask myself: am i really love physics or am i just used to be good at it? that's a question, seriously. maybe there are something more interesting but i didn't have chance to get to know them before. so what should i do? keep hesitating like this?
"if you give yourself to mathematics, mathematics will give you the world." i try to believe that..
i am thinking about writing somethong about him, a boy i think i have a crush on. or maybe it's mutual, love at first sight. i dont know. it is late, maybe i can write about this tomorrow.
sweet dreams, to me and everyone who is trying to sleep now.^^
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