A novel multimodal optical cancer detection system appears to be able to maximize cancer cell detection during surgery, according to a report published June 28 in Cancer Research. Researchers from the Montreal Neurological Institute and Hospital and McGill University in Montreal, Quebec, Canada, developed an in situ, intraoperative, optical cancer detection system that combines intrinsic ﬂuorescence spectroscopy (IFS), diffuse reﬂectance spectroscopy (DRS), and Raman spectroscopy (RS).
Using this device, they found that cancers of the lung, colon, and skin could be detected in situ during surgery with 97% accuracy, 100% sensitivity, and 93% speciﬁcity.
In a validation study of the optical system among 15 patients with grade II to IV gliomas and metastatic brain cancers, imaging was greatly enhanced. Measured as area under the curve (AUC), the ability to detect cancer increased by as much as 5%, from 95% with use of RS alone to up to 100% with all of the modalities combined.
The team is now testing the device in a clinical trial in patients with glioma and has already begun seeking regulatory approval in the United States.
The results so far are indicative of approaching the threshold for complete resection and its associated survival beneﬁts, note the authors.
“We have tested it in brain, lung, breast, colon, skin, and prostate cancers,” said senior coauthor, Kevin Petrecca, BSc, MD, PhD, William Feindel Chair in NeuroOncology at Montreal Neurological Institute and Hospital. “It is highly accurate in these types — we have not yet tested it in other types — but it can be used to detect cancer in at least all of those types.”
The system can be developed for laparoscopic, biopsy, and endoscopic procedures as well, Dr Petrecca told Medscape Medical News.
“We believe it will significantly improve cancer surgeries,” he said. “We have started a clinical trial in brain cancer to specifically address this question.”
“We have begun the process of seeking regulatory approval in the US, but the timing in completing this process is not yet clear,” added Dr Petrecca.
Validation of Integrated System
In 2015, the research team developed a hand-held RS probe that allowed surgeons to accurately detect cancer cells in real time during surgery. In that setting, RS demonstrated highly speciﬁc and sensitive cancer detection when used for a variety of types, but its detection accuracy values were generally limited to approximately 90%. Similarly, oncology applications using IFS and/or RS have also been limited.
The authors hypothesized that IFS and DRS have the potential to synergistically complement the molecular information provided by RS, which would maximize the ability to detect cancer. To test their hypothesis, Dr Petrecca, together with Frédéric Leblond, PhD, professor of engineering physics at Polytechnique Montréal, and their colleagues, developed an integrated cancer detection system that combined IFS, DRS, and RS.
In their validation study with patients with brain cancer, 10 to 15 sites were interrogated for each of the 15 patients, for a total of 161 sites. The tissue was then sampled at each site for blinded postinterrogation neuropathologic analysis to determine whether cancer cells were present.
The AUC for RS and IFS combined was 0.98 for detecting glioma and 0.99 for either the metastasis or all cancers combined categories. The researchers found that the synergistic contribution of IFS to RS added as much as 0.05-point increases in AUC.
Similarly, adding IFS to RS could lead to a 5–percentage point increase in accuracy (from 93% to 98%), a 10–percentage point increase in sensitivity (from 90% to 100%), and a 3–percentage point decrease in specificity (from 97% to 94%) for gliomas.
The study was funded by the New Researchers program from the Fonds de recherche du Québec– Nature et technologies, the Discovery Grant program from Natural Sciences and Engineering Research Council of Canada (NSERC), and the Collaborative Health Research Program by the Canadian Institutes of Health Research and NSERC. Dr Petrecca serves as chief medical officer and Dr Leblond serves as chief technical officer at ODS Medical Inc, a diagnostic medical device company they founded in 2015.