Juliet Matgen
September 20th, 2013
WRIT 340
iKnife: The Cutting Edge of Surgery
ABSTRACT:
The iKnife has the potential to revolutionize oncological surgery. Expanding on existing
surgical technology, the iKnife has the capacity to analyze ‘smoke’ released from cauterized
tissue during surgery and deduce whether or not it is cancerous. This new innovation has the
potential to greatly increase the chances of successful tumor removal the first time around,
eliminating the need for common and often expensive follow up surgeries. Preliminary tests with
the iKnife have revealed the technology to be incredibly accurate and if similar results are seen
in clinical trails, the iKnife could begin to be implemented in operating rooms all around the
world in the coming years.
INTRODUCTION:
Each year, approximately 7.6 million people around the world die from cancer [1].
While there are many different methods for treating cancer, in many cases surgery is the best
option. However, this is not always as straightforward as it might sound. When a surgeon is
removing something like a tumor, the method is most often to cut through healthy tissue around
the periphery of the tumor to ensure that the whole tumor is removed [2]. However, in many
cases the dividing line between healthy tissue and cancerous tissue is not obvious. The surgeon
might accidentally miss the boundary and leave behind pieces of the tumor, or take out excessive
amounts of healthy tissue, which could be dangerous in procedures that require extreme
precision, such as neurosurgery [3].
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Currently, in cases of uncertainty, removed tissue samples are sent to pathology
laboratories where they are analyzed and deemed cancerous or not. However, this process can
take up to 30 minutes and greatly increases the length and cost of the surgery [4]. This method is
currently the best available option, but is by no means perfect. Malignant tissue is still missed
even by the most experienced surgeons. In fact, it is reported that as many as one out of every
five breast cancer surgeries is not completely successful the first time, resulting in the need for
additional procedures to remove the missed portions of the tumor [5].
The iKnife, developed by Dr. Zoltan Takats at the Imperial College London, has the
potential to revamp the world of surgery, providing virtually instantaneous feedback about
whether tissue is cancerous or not. As the iKnife cuts into tissue, it analyzes every piece of the
sample and reports whether it is cancerous or not within seconds [3]. The iKnife is unlike any
other device seen in the operating room and has tremendous promise to increase efficiency and
lower the cost and length of many surgeries.
HOW DOES IT WORK?
The “iKnife” electrically cauterizes, or burns, small bits of tissue as the surgeon makes
incisions. This electrocautery method is often used to limit blood loss during surgeries and
releases “smoke,” or tiny particles and ions from the tissue [6]. Cauterizing knives are already
used in surgeries around the world, but what is new about the iKnife is that the smoke released
by this process is now being collected and analyzed. Currently, in most surgeries the smoke that
is released is seen as a nuisance. It is strongly odorous and can sometimes even obstruct the
vision of the surgeon. [7] However, the iKnife has a vacuum component near its tip that sucks up
some of this smoke and conveys it to a rapid evaporative ionization mass spectrometry (REIMS)
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system [6]. A long tube attached to the knife component conveys the smoke from the site of
operation to the REIMS system where it is analyzed and determined to be cancerous or not. This
analytic component uses mass spectrometry to identify the signature of the tissue. In the REIMS
system the ionized particles are sent through magnetic and electric fields to produce a spectra
that provides useful information about the specific molecule or ion such as its weight and
fragmentation pattern that allows it to be identified [8].
According to the American Association for Cancer Research, “tumors have different
chemical signatures than healthy tissue. Analysis of these signatures via mass spectrometry could
help cancer surgeons remove tumors but leave suitable margins for healthy tissue” [3]. In other
words, the REIMS method essentially assesses the released particles in the smoke and compares
the results from the patient’s tissue to a database of previously determined samples [6].
Based on the results of the comparison, a red or green signal will appear on a screen
facing the surgeon and alert the surgeon as to whether the tissue they are cutting through is
cancerous or not [9]. Figure 1 illustrates one of the developers, Julia Balog, watching these color
changes as she uses the iKnife on a piece of sample tissue. One of the impressive capabilities of
the iKnife is its rapid processing speed. With an average feedback time of 0.7 seconds, the iKnife
provides virtually instantaneous results to the surgical team, allowing for not only more accurate
tumor extractions, but quicker procedures as well [3].
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Figure 1: Developer Julia Balog experiments with the iKnife on a small piece of tissue at St. Mary's hospital in
London. Availible at http://www.hngn.com/articles/7975/20130717/smart-knife-sniffs-out-cancer-willpatients-operating-table-faster.htm#page3
IS IT WORTH IT?
In theory the iKnife seems promising, but realistically is it a feasible option? Currently,
Takats’ iKnife design costs over $380,000 to build but this price is expected to decrease
significantly if the product were commercially manufactured [4]. Furthermore, Takatas’ team
argues that the implementation of the iKnife in hospitals could ultimately save them money. By
enabling hospitals to downsize their pathology departments due to a lower demand for
pathological testing during surgical procedures, hospitals could cut costs. The iKnife could also
cut hospital expenditures by reducing the time of many surgeries and eliminating follow up
procedures due to incomplete tumor removals [4].
The fundamental components of the iKnife such as mass spectrometry and cauterization
are already well known and practiced. Due to the familiarity of these methods, the time it would
take for surgeons to learn how to implement the iKnife in clinical practice could be greatly
reduced. There would still have to be some training to learn how to set up the machine and
interpret the results, but this would be much simpler than learning an entirely new operational
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technique. Nicholas Winograd, PhD professor of chemistry at Penn State, commented, “getting
mass spec into the operating room is a holy grail, and [the iKnife] has taken us closer to it” [3].
Usually the level of statistical analysis performed by the iKnife would require years of chemistry
training before doctors could implement it. However, the iKnife is able to bridge this gap making
it feasible for mass spectrometry to easily be used in the operating room [3].
To prove that the iKnife in clinical settings is more than just a good idea, the developers
must be able to show with concrete data that this device is more efficient than existing
techniques. While the available data has proven promising, it is not conclusive. The Takats group
collected 3,000 tissue samples from 302 cancer patients and the results of the iKnife reportedly
matched that of traditional methods of pathology testing in every single trial [10]. However,
there is no way to tell if the current database of collected cancerous tissue samples is
comprehensive enough. The system has no way of recognizing a type of cancer that it is not
programmed to look for. This raises a potential cause of concern regarding identifying rare or
new cancerous tissues. These preliminary results, while tempting, are not enough to conclude
that this device would solve the issue of incomplete tumor extraction as perfectly as the
developers might hope. In order to gain the trust of patients, as well as surgeons, a much larger
data set is required.
FUTURE:
While there is a lot of excitement about the iKnife, it is important to remember that it is
still a ways away from being used commercially. While the current available test results do not
provide enough evidence to completely confirm the iKnife’s viability, it is enough to cause a stir
within the medical community and to excite many practicing surgeons. Emma King, a surgeon at
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Southampton hospital in England stated that the iKnife is, “a really exciting innovation and a
very promising technique for all types of surgery” [11].
Even though the device will not be able to reach the commercial market for some time,
the possible impact that the device could have is tremendous. Providing practically instantaneous
feedback about the makeup of a tissue sample, the applications for the iKnife seem endless.
While originally designed for use in tumor removal, if the iKnife proves a success it could be
applied to almost any type of surgery. Theoretically, any sort of unknown tissue type could be
rapidly classified using this method and could help surgeons know exactly what they’re looking
at [3].
The success of the iKnife has the potential to dramatically reduce the number of
secondary surgeries while also shortening the length of surgical procedures and providing the
most precise methods of extraction. The iKnife still needs to go through many more trials before
it can be routinely used in surgery and while the developers hope to see the same results in
clinical trials that they have seen in the pilot study, it is hard to make conclusions at this point. If
the clinical trials are successful, Takats hopes that within a few years the iKnife might be found
in all operating rooms.
WORK CITED:
[1] “Cancer Prevention and Control.” Center for Disease Control and Prevention. ( 2013, June
23). [Online] Availible: http://www.cdc.gov/cancer/dcpc/resources/features/WorldCancerDay/
[2] “Cancer Surgery: Physically removing Cancer,” Mayo Clinic. Accessed September 20, 2013.
[Online] Availible: http://www.mayoclinic.com/health/cancer-surgery/CA00033
[3] “Surgical iKnife Identifies Cancer Tissue” Cancer Discovery. (2013, August 1) [Online]
Availible: http://cancerdiscovery.aacrjournals.org.oca.ucsc.edu/content/3/9/959.1.full.pdf
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[4] D. Thompson. (2013, July 17). “iKnife tells surgeon whether tissue is cancerous” [Online]
Availible: http://www.webmd.com/cancer/news/20130717/experimental-iknife-tells-surgeonwhether-tissue-is-cancerous
[5] J. Gallagher. (2013, July 17). “Cancer surgery:Tumor ‘sniffing’ surgical knife designed” BBC
News -Health [Online] Availible: http://www.bbc.co.uk/news/health-23348661
[6] J. Balog, L. Sasi-Szabo, J. Kinross, M. Lewis, L Muirhead, K. Veselkov, R. Mirnezami, B.
Dezso, L. Damjanovich, A. Darzi, J. Nicholson, Z. Takats. (2013, July 17). “Intraoperative
Tissue Identification Using Rapid Evaporative Ionization Mass Spectrometry” Cancer
Diagnostics [Online] 5(194). Availible: http://stm.sciencemag.org/content/5/194/194ra93
[7] W. Barrett, A. Garber. (2003, June 17). “Surgical smoke: a review of the literature. Is this just
a lot of hot air?” Surgical Endoscopy. [Online] 17(6) 979-87. Available: http://www.ncbi
.nlm.nih.gov/pubmed/12640543
[8] Reusch, W. (2013, May 5). “Mass Spectrometry.” [Online] Availible: http://www2.chem
istry.msu.edu/faculty/reusch/VirtTxtJml/Spectrpy/MassSpec/masspec1.htm
[9] J. Balog, T. Szaniszlo, K. Schaefer, J. Denes, A. Lopata, L. Gordorhazy, D. Szalay, L.
Balogh, L. Sasi-Szabo, M. Toth and Z. Takats. (2012, August 3). “Identification of biological
tissues by rapid evaporative ionization mass spectrometry.”Analytical Chemistry [Online]
82(17), 7343-7350. Availible: http://p8888ucelinks.cdlib.org.oca.ucsc.edu/sfx_local?sid=Entrez
:PubMed&id=pmid:20681559
[10] M. Boyer. (2013, July 18). “The iKnife Helps Surgeons Find Tumors by Sniffing Out
Cancer” [Online] Availible: http://inhabitat.com/the-iknife-sniffs-out-cancer-helping-surgeonsfind-tumors/
[11] B. Hirschler. (2013, July 17). “Scientists have created an “intelligent” surgical knife that can
detect in seconds whether tissue being cut is cancerous, promising more effective and accurate
surgery in future” [Online] Availible: http://uk.reuters.com/article/2013/07/17/us-cancer-knifeidUKBRE96G12620130717
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