Relationship between cancer tissue derived and exhaled volatile organic compound from colorectal cancer patients. Preliminary results

New insight into the omic sciences suggests that volatile organic compounds (VOCs) contained in exhaled breath can reflect the healthy or disease state of patients, representing an attractive, promising and non-invasive method of medical investigation. This approach has recently been proposed as a new potential screening tool in colorectal cancer (CRC) patients. However, a possible correlation between the exhaled VOCs and those produced by the cancerous tissue has never been investigated. In this preliminary study, we compare the VOCs exhaled by seven patients affected by CRC with those produce by own cancer tissue and normal colonic mucosa. The VOCs contained in the exhaled breath were sampled with the ReCIVA breath sampler©, while those produced by ex-vivo human tissues weresampled by headspace solid-phase microextraction (HS-SPME) at different incubation times after surgery. In both cases, the collected VOCs were analyzed by Gas Chromatography with Mass Spectrometry (GC–MS). Benzaldehyde, benzene ethyl, benzene methyl, butanoic acid, dodecanoic acid, indole, nonanal, octanoic acid, pentanoic acid, phenol and tetradecane were the VOCs most frequently detected both in the exhaled breath and secreted by tissues. The results showed that cancer tissue and normal colonic mucosa from the same patient produced a similar VOCs pattern but with different fingerprints. In particular, the concentrations of benzaldehyde, benzene ethyl and indole were significantly different in cancer tissue respect the normal colonic mucosa. In conclusion, these preliminary data suggest the involvement of the three compounds in CRC by encouraging further investigation.