New technique could sniff out malignancies

Breath tests are usually used to test for drunkenness, or perhaps halitosis. But Dr. Hossam Haick of the Technion has found a new use for breath tests – determining whether or not a growth in the lung is benign, or malignant.

Right now, patients who are diagnosed with cancer are often given a CT scan by doctors, in order to determine, among other things, a cancer’s malignancy. But a new technique developed by Haick and his team shows that breath testing could be used to discriminate between benign and malignant pulmonary growths. Haick reported significant results using the technique in the upcoming issue of the Journal of Thoracic Oncology, writing that “the reported breath test in this study could have significant impact on reducing unnecessary investigation and reducing the risk of procedure-related morbidity and costs.”

As part of the study, Haick and his team studied 74 patients at a Colorado clinic who were being checked for pulmonary growths between March 2009 and May 2010. According to research conducted by Haick and his team, cancer patients emit certain characteristic elements in their breath. Researchers had the patients breathe out using a special device invented by Haick, and their breath was analyzed using gas chromatography and mass spectrometry (two chemical analysis methods for vapors), along with information from chemical nanoarrays developed by Haick and his team.

The data distilled from the tests was stored, and compared with more traditional methods of judging a growth’s malignancy, such as bronchoscopy, wedge resection, or lobectomy. After 24 months — time enough for doctors to see whether a growth was malignant — the results were compared with the data from the breath tests.

The results were better than anticipated. Haick’s system accurately identified 53 malignant and 19 benign growths. And, in addition, the nanoarrays used by the team were able to successfully distinguish between squamous cell carcinoma and adenocarcinoma (important for treatment purposes), and whether or not the cancers were advanced or still in an early stage. The technique could be used on other cancers as well, depending on the analysis methods used, the Technion said.

The study was an extension of Haick’s work on his “electric nose,” which can be used to “sniff out” cancer — a much more effective system than those currently available.

“Current cancer diagnosis techniques are ineffective and impractical,” said Haick. “Mostly the patient arrives for diagnosis when the symptoms of the sickness have already begun to appear. Months pass before a real analysis in completed. And the process requires complicated and expensive equipment such as CT and mammography imaging devices. Each machine costs millions of dollars, and end up delivering rough, inaccurate results.”

The new method, said Haick in his report, “could facilitate faster therapeutic intervention, replacing time-consuming clinical follow-up that would eventually lead to the same intervention.”