There are more than 200 different types of cancers.
According to the US National Cancer Institute, nearly 40% of Americans will be
diagnosed with cancer during their lives. The World Health Organization names
cancer as the second leading cause of death globally, causing nearly one in six
deaths. In case anyone needs reminding, cancer is a big deal. Lung cancer is the leading cause of cancer deaths
around the world, causing more deaths than prostate, breast and colon cancers
combined. Only 18.5% of patients will survive five or more years after being
diagnosed with lung cancer. So smokers, take note! Alongside chemotherapy and
surgery to remove tumors, about 40% of cancer patients are treated with
radiotherapy, which fires ionizing radiation into the body, killing malignant
cells with X-ray photons. Roughly 17,000 clinics worldwide deliver X-ray
radiotherapy treatment today.
The rise in popularity of proton therapy (vs
X-ray) is continuing across the globe. It is estimated that more than 165,000
patients suffering from a variety of cancers, such as prostate cancer, brain
tumors, etc. have already been successfully treated using this method. In fact,
the proton therapy market is on track to become a multibillion-dollar industry
by 2024. The number of proton therapy centers is increasing globally. Still,
industry experts believe that players will miss out on a majority of cancer
patients who can benefit with proton therapy, overlooking a huge
multi-Billion-dollar potential market.
The proton therapy market is likely to almost double
by 2024 from its current market value. Globally, the numbers of patients
treated with proton therapy is very low whereas the potential candidates for it
are in the Millions.
Shortly before 1975, I had started promoting Varian’s Clinacs throughout the Middle East (back then it was not
yet proton beams but x-ray and electron beams) and Linacs (for inspecting fully
loaded shipping containers). Unfortunately, the effort
died in its track because of the Lebanese civil war and by October 4, 1976 I reported to
work in Zug, Switzerland, not for the Medical group but for the Industrial
Product Operation which was mainly semiconductor equipment and instruments
based around high or ultra-high vacuum technology.
While I never got to sell any Clinacs or Linacs, at
least I was for a very short period exposed to the technology (including a
visit to Palo Alto where they were manufactured). The technology had been
pioneered years earlier at the 2-mile long SLAC accelerator of Stanford University, by Dr. Edward Ginzton, a Ukrainian-American engineer
and Bill Hansen. As a student at Stanford, Ginzton worked with William (Bill)
Hansen and brothers Russell + Sigurd Varian. In 1941 he became a member of the
Varian-Hansen group at the Sperry Gyroscope Company and some years later joined
the Varian brothers on their board of directors at Varian Inc. Palo Alto,
California.
Actually, the first clinical Van de Graaff generator
treatment was done at Harvard’s Medical School in 1937.
In 1972, a Dr. Peter Fessenden joined Stanford and
began developing a linear accelerator that combats tumor cells using two types
of radiation. Working with Varian Medical group, Fessenden’s team creates the
first linear accelerator that combined both X-ray and electron
treatment. So, Varian holds the claim to fame for developing the first
medical linear accelerator in cooperation with Fessenden and his team. Since
then, the company has developed a portfolio of technologies to treat and manage
cancer, including equipment for radiotherapy, radiosurgery, brachytherapy, and
proton therapy. Seems their Linac line for shipping containers either didn’t
fly or got sold off; I lost track of that line long ago though I’m partly back
in that fold with gamma ray detectors mainly as a tool to counter potential
radiation terrorism (homeland security type equipment).
But post-WW2, cobalt therapy was the medical use of
gamma rays from the radioisotope cobalt-60 to treat cancer. It was then widely
used in external beam radiotherapy machines, which produced a beam of gamma
rays which was directed into the patient's body to kill tumor tissue.
Radiotherapy doctors were not yet hot on clinical linac technology; it was not
yet the tool of choice. Indeed, when I started peddling Clinacs to any medical
center with a semblance of serious oncology department, my main technology competitor
was Cobalt-60 systems which back then were fairly well established in most
Western nations.
Philips introduced their SL25 in 1985, it was the
“first fully digitally controlled” medical linear accelerator. They continue to
be in many other medical equipment but no longer in proton therapy systems.
In proton therapy, the proton beam is generated
through use of a particle accelerator, which uses electromagnetic fields to
accelerate protons to very high energies. The use of protons to deliver radiation
therapy allows physicians to maximize the radiation dose to the treatment
target, while minimizing the adverse effects of radiation on the surrounding
healthy tissue. (For those of you who no longer remember kindergarten physics,
protons and neutrons makeup the nucleus of atoms.
Similar to traditional X-ray therapy, proton therapy
is an external beam radiation therapy technique. High-energy protons deposit
radiation dose in a more targeted manner than X-rays. When protons enter the
body, they only leave a small amount of radiation along their path as they pass
through the tissue. Upon reaching a specific depth, protons deposit a large
focused amount of radiation and then stop, leaving virtually no radiation
beyond that depth.
Today, while clinical linear accelerators are available in approximately 65 facilities
worldwide. A few very poor nations in Africa and Latin America also have such
capabilities, though probably far too few for the size of some of their
populations. Not only do they need the therapy machine but also the imaging
techniques as well as the sophisticated software programs dedicated to that
type of intervention. It amounts to millions and millions in investments. The
dominant players in proton therapy are IBA, Mitsubishi, Optivus, Hitachi, Mevion, Varian,
ProNova, Sumitomo.
One shortcoming of stand-alone proton
machines as seen below is they suffer from the same inherent issues that all
cyclotrons and synchrotrons do, such as slow beam-energy modulation that’s
problematic for accurate targeting. It can be overcome by adding a therapy
station on a beamline, but this can mean systems with the footprint of a sports
field, impossible for most hospitals. So, many accelerator labs worldwide have
extended their beamline capabilities to include a “home-made” radiation therapy
ward. It’s the case for South Africa, near the Stellenbosch wine country,
iThemba have a therapy ward. In Switzerland, at the Paul Scherrer Institute, they
rank among the most advanced for ophthalmology cancer therapy. In Geneva,
Proton Beam Therapy and CERN hadron technology are fighting cancer with LIGHT;
this accelerator produces a proton beam of 230 megaelectron volts traveling at
60 percent of the speed of light, almost 181 million m/s !
