Donato Francesco Altomare is a celebrated professor of coloproctology and colorectal cancer specialist at Università degli Studi di Bari whose keynote on using beathomics in the fights against colorectal cancer gave delegates real pause for thought at ESCP 2018.
The session was chaired by ESCP’s Guidelines Committee Mark Katory who the audience as encouraged the by promising findings so far as well as the potential of this new discipline to positively impact treatment and outcomes for colorectal cancer.
Professor Altomare started by explaining the greatest challenges of modern oncology related to too-late detection and fast progression of symptoms while treatment is being planned and constructed. While prevention is better than cure, early and more accurate screening is just as vital – it saves lives.
However, the most common screening tests available still have low compliance from patients, low sensitivity and are still relatively high risk and costly.
For many years, clinicians have been looking at various “omics” to see if early detection can be improved by understanding issues right down to the smallest level. Genomics, transcriptomics and proteomics have all contributed to greater understanding o subtle changes to physical which can indicate something has gone away.
Metabolomics is the most recently developed component of “omics” research, examining the end-points of cellular metabolism by using a range of techniques including high-throughput (HT) technologies. It is understood by observing that exhaled breath contains thousands of volatile organic compounds (VOCs) produced by the metabolism in the body, which useful as biomarkers for diseases, including cancer.
By isolating and identifying endogenous VOCs in exhaled breath, it is expected that we can identify the ‘breathprint’ of any human disease. . . this gives rise to new strategies in colorectal cancer screening.
VOCs are a heterogeneous group of organic compounds with the common feature of having a boiling point between 50°-260°. Our olfactory receptors are already programmed to detect issues and examples through the ages, from superstitions to clinical observations have hinted that what we all know deep-down to be true: disease stinks!
Consider breath odours in human diseases:
- Ethanol in the breath of drinkers
- Sweet smell of acetone in the breath of diabetic patients
- Uremic fetor (urine-like smell breath in chronic renal failure, ammonia in the saliva)
- Breath that smells like faeces can occur with prolonged vomiting, especially when there is a bowel obstruction.
Professor Altomare explained cancer tumours place oxidative stress on cells which, through burning polyunsaturated fatty acids, emit VOCs which can be detected.
There have been numerous studies of VOCs for each part of the body and also looking specifically at VOCs related to cancer, including Professor Altomare’s own 2013 study. He kindly took us through a number of these to understand the findings pertaining to colorectal cancer, with the overall conclusion that there are easily demonstrable VOCs present in those suffering from colorectal cancer, even before major symptoms show.
What’s more, the VOCs pattern from CRC patients is clearly modified by cancer removal confirming the tight relationship between cancer metabolism and exhaled VOCs. It seems, therefore, that VOCs analysis could have a high reliability to identify patients disease-free after curative CRC resection.
Professor Altomare then talked through what we still need before we can develop an optimal breath screening test, including further screening tests and development of a cost effective and easily transportable device for testing. Isolating specific VOC molecules remains a key challenge. Although the analysis of VOCs linked to cancer is a new frontier in the early diagnosis of this disease.
Ideally, we will one day enjoy a world where breath samples form part of routine checkups. But if we get the tehcnology right, the possibilities are endless.
As Professor Altomare concluded, this is a new frontier of medical exploration - like astronomers did back in the time, relentlessly scourging the sky, looking for combinations of stars in the vast universe out there to find answers to human-centric fundamental questions, we are trying to pick up sensible combinations of molecules in exhaled breath, in order to find out the discriminant constellation of cancer-related VOCs.