Breath Analysis and Ex-Vivo Lung Perfusion
On Tues ., Aug . 1 , the GLMS Foundation Senior Physicians Speaker Series welcomed Dr . Victor van Berkel to speak on breath analysis and ex-vivo lung perfusion . Dr . van Berkel is a Thoracic Surgeon at UofL Health and a Professor in the Department of Cardiovascular and Thoracic Surgery .
There are 1.35 million new cases of lung cancer per year and 1.18 million deaths , and it is the second most common cancer in the U . S . Lung cancer is the leading cause of cancer deaths in the U . S . at 28.7 % of all cancer mortalities , more than colorectal , breast and prostate cancer combined . It ’ s so fatal because most of the time when people have the disease , they have minimal or no symptoms . As with most diseases , there are better treatment options when diagnosed at early stages . The question becomes : how do we find more patients who have very early-stage disease rather than someone in late stages ? The answer is : lung cancer screenings .
With the number of deaths in the U . S ., the National Cancer Institute funded and organized a multi-center trial called the National Lung Screening Trial which looked at yearly chest X-rays vs . CT scans on high-risk populations . They screened once a year for three years and then followed up for five years after , using cancer mortality as the endpoint for the study . They enrolled over 50,000 patients and published results in 2011 . When looking at cancer deaths associated with the two groups , there were 356 deaths in
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the CT group and 443 deaths in the chest X-ray group , leading to a relative reduction of 20 % mortality . In order to save one life , you must screen 320 patients . There was a 96.4 % false positive rate for those in the CT group and a 94 % false positive rate in the plain films group , resulting in a large financial and resource burden of follow-up .
Knowing there had to be a better way to screen , breath testing became an option . Of the many chemicals present in breath , they were most interested in carbonyl compounds , those that arise from the interaction of oxygen free radicals with unsaturated fatty acids . In cancer , a lot of the reactive oxygen species get produced due to the hypoxic conditions around a lot of tumors . They began working on a project to create a silicon microreactor coated with a compound that would react with carbonyl compounds and would trap them for analysis . They take a 1L bag of air and bring it down to 10mL worth of volume , a 10,000-fold concentration . They found that there were four carbonyl compounds present at higher concentrations in patients with lung cancer . In 412 patients , 162 had cancer . For every one marker positive , 97 % of the patients with cancer were captured with a 54.5 % specificity . With more positive markers , specificity increased – three positive markers gave a specificity of 96.4 %. This test is cheaper , faster and lower risk than a CT scan . Post-resection studies showed that the marker rates normalized to the control population , and they were indeed measuring something coming from the tumor itself . From this , they founded a company in 2015 called Breath Diagnostics , Inc . in an effort to bring this to