Friday, June 14th, 2013 at 9:09 am
Imagine a test in which a woman visits a clinic, a sample of blood is acquired from a simple pin prick of her index finger, and within a few minutes the blood is analysed and a definitive diagnosis is made. She either has breast cancer or she does not. So, the question we explore is: Does such a test yet exist?
A year ago, scientists from Imperial College in London published a paper in Cancer Research in which they reported their discovery of a strong association between the risk of breast cancer and a molecular change in a particular white blood cell gene called ATM. Looking for a chemical effect called methylation which switches genes on and off, they analysed blood samples from almost 1400 women — almost half of whom developed breast cancer between 3 and 11 years later. The researchers showed that women with the highest methylation levels in the ATM gene were twice as likely to develop cancer as those with the lowest levels.
Earlier this year, Emanuel Petricoin presented a paper at the Miami Breast Cancer Conference in which he reviewed the development of new blood tests for both the early detection and treatment of breast cancer. One of the approaches that he highlighted was a test based on unique glycoproteins that can be identified by quantitative mass spectrometry of breast tumours. The basic premise is that proteins associated with the tumour find their way into the blood stream, thus serving as a biomarker.
Invasive ductal carcinoma cells. Copyright Carcinogenesis.
Perhaps one of the most promising techniques has been developed by Henri Tiedge at the State University of New York Downstate in Brooklyn. He studied regulatory ribonucleic acids (RNAs) — specifically brain cytoplasmic RNAs — that are important mediators of gene expression in nerve cells. Realising the importance of his work, Tiedge secured a US patent (7,510,832), and subsequently published his groundbreaking findings in Carcinogenesis. The RNA was expressed at high levels in invasive breast carcinomas but was not detectable in normal breast tissue or benign tumours such as fibroadenomas. Tiedge has recently been awarded a $50,000 grant to assist in commercialization of his blood test.
Although breast cancer tests based on biomarkers in the blood stream will soon be available in the clinic, they will not replace diagnostic imaging devices such as our dual-modality Aceso system. To treat a patient with breast cancer successfully, the doctor needs to know exactly where the lesion is located.
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Friday, June 7th, 2013 at 9:00 pm
Yesterday was a glorious winter’s day in Cape Town, offering welcome respite from the inclement weather. As we stood on the steps of Jameson Hall, looking out to the east, we marvelled at the snow-capped mountains of the Hottentots Holland range. Forty-seven years ago to the day — on 6 June 1966 — Senator Robert Kennedy delivered one of the greatest speeches of his career entitled “Day of Affirmation” in the Jameson Hall. He provided a ripple of hope to the opponents of apartheid — both black and white — at a time when many South Africans felt isolated from the outside world.
The occasion yesterday was the mid-year graduation ceremony at the University of Cape Town for the faculties of engineering, health sciences and science. For the students, over fifty of whom received their doctoral degrees, this was an auspicious occasion. Their commencement was undoubtedly a day of affirmation, when all their hard work was rewarded, with five of the graduates having an affiliation with CapeRay.
James (L) and Nielen (R)
Two of the students have recently been recruited to full-time positions at the company. For his MSc (Med) in biomedical engineering, software engineer Nielen Venter studied very small muscle contractions, or twitches, to establish how electrical stimulation can be applied to the control of neural prostheses. James Boonzaier, who joined CapeRay as a mechanical designer at the beginning of the week, earned an MSc in mechanical engineering for his innovative technique to aid in the restoration of maxillofacial anatomy. Known as distraction osteogenesis, James and his surgical collaborator used this approach for the successful treatment of four patients.
Daniel Auger, who worked for CapeRay as a research engineer in 2011, earned his PhD in biomedical engineering for his work on mapping the myocardial mechanics of the right ventricle using 3D magnetic resonance imaging. Adijat ‘Wumi’ Inyang, supervised by CEO Kit Vaughan, earned her PhD for the development of a novel meniscal prosthesis for the knee based on composite materials, while Miné Zantow, mentored by CapeRay director Tania Douglas, was awarded an MSc for her thesis on the use of image analysis to determine the size and behaviour of droplets in microfluidic systems.
The guest speaker was Derek Hanekom, our country’s Minister of Science and Technology, who, in offering encouragement to the graduates, invoked the words of Mahatma Gandhi, “Live as if you were to die tomorrow. Learn as if you were to live forever.”
Friday, May 31st, 2013 at 11:11 pm
Eighteen months ago we wrote about the potential of tablet personal computers to play a disruptive role in healthcare. The iPad is now the undisputed tablet leader and consumers, especially busy clinicians, have been quick to exploit this device’s potential. A recent report by Novation has concluded that the latest iPad released by Apple in 2012 has made it easier for radiologists to review images and, in some cases, to make a diagnosis when away from their workstations.
Just published in the American Journal of Roentgenology is a paper by a group of Japanese researchers from Nagoya who studied the ability of neuroradiologists to diagnose acute cerebral infarction when viewing brain CT images. They compared a 21-inch high-resolution LCD monitor with the original iPad and concluded, “Our results show a small difference between medical-grade LCD monitors and iPad, and this is acceptable compared with past reports.” The newest iPad, with four times the resolution (2,048 x 1,536 pixels) and its Retina display, will surely mount a serious challenge to the traditional LCD monitor.
The Mayo Clinic, established in Rochester, Minnesota in 1889, is among the world’s most prestigious medical centres. They have always been at the cutting edge of medical technology — the heart-lung machine was developed there in the early 1950s — and in 2013 they have adopted Apple’s mobile devices on a grand scale. There are more than 15,000 iOS devices (iPhones and iPads) connected to the clinic’s network and in daily use by their staff who run custom in-house applications (or “apps”). One such app called Synthesis enables physicians to have instant access to patient records, including CT scans and laboratory results.
As we reported last year, at CapeRay we designed our user interface for the Soteria around an iPad. The radiographer can use gesture-based interaction — pinch to zoom, two finger panning to move the image around, and one finger sliding for contrast control — to review the captured images (see one of Soteria’s first mammograms at left). However, as emphasized by Nephosity, who recently secured FDA approval for their MobileCT Viewer, the iPad may not (yet) be used to diagnose breast cancer.
“Disruptive innovation” is a term introduced by Clayton Christensen 15 years ago in his book The Innovator’s Dilemma, describing how a product gains a foothold at the bottom of the market, moves relentlessly upward, and then finally surpasses well-entrenched competitors. Within just three years the iconic iPad would appear to be on that upward trajectory.
Imagine a test in which a woman visits a clinic, a sample of blood is acquired from a simple pin prick of her index finger, and within a few minutes the blood is analysed and a definitive diagnosis is made. She either has breast cancer or she does not. So, the question we explore is: Does such a test yet exist?
June 14, 2013 at 7:13 pm
Hmmmmm. “they analysed blood samples from almost 1400 women — almost half of whom developed breast cancer between 3 and 11 years later. The researchers showed that women with the highest methylation levels in the ATM gene were twice as likely to develop cancer as those with the lowest levels.”
“Half” of a sample of women developed breast cancer! This is obviously a sample of women at risk, like BRCa1 carriers, and not a normal population. “Twice” as likely…
“Half” and “Twice” are not part of the complicated and unforgiving science that I know.
June 16, 2013 at 4:32 am
My summary was necessarily brief, David. I quote from the abstract: “Samples were from a case–control study derived from a cohort of high-risk breast cancer families and nested case–control studies in two prospective cohorts”. So, as you can see, this was not a random sample from the population. I will send you a copy of the paper under separate cover.
June 15, 2013 at 10:10 am
The BC200 RNA looks more promising – maybe we are moving in the right direction. Bottom line, none of these markers are going to put CapeRay out of business in the near future!
June 15, 2013 at 11:31 am
But the blood test will surely replace screening mammography?
June 16, 2013 at 4:35 am
As David has suggested, Michael, these blood tests obviously will not replace mammography until both sensitivity and specificity approach 100%. That of course is the challenge for anyone developing a useful screening tool!
June 18, 2013 at 11:40 am
From my readings over the past few years, and I understand it is a hotly debated figure, the sensitivity of screening mammography is at best 70% and specificity over 90% (although benign DCIS isn’t accounted for)
With the rapid advances happening in the “-omics” and biomarker discovery, particularly as the genomic database for breast cancer builds (eg. see http://www.foundationmedicine.com/) and the multiple genes (>>2) involved are discovered, I think its only a matter of time before that 70% figure is going to be seriously challenged.
June 15, 2013 at 1:29 pm
Michael: 50% is a poor sensitivity (you act on high 90′s); no specificity (false +ve) is given. Also, the glib “half” and “twice” reek of “smoothing” and perhaps even thumb-suck.