Oncotarget published "Scent test using Caenorhabditis elegans to screen for early-stage pancreatic cancer" which reported that although early detection and diagnosis are indispensable for improving the prognosis of patients with pancreatic cancer, both have yet to be achieved. Except for pancreatic cancer, other cancers have already been screened through scent tests using animals or microorganisms, including Caenorhabditis elegans.
In this study, the authors organized a nationwide study group comprising high-volume centers throughout Japan to collect patients with very-early-stage pancreatic cancer. They initially performed an open-label study involving 83 cases, with subsequent results showing significant differences after surgical removal in stage 0–IA. Preoperative urine samples had a significantly higher chemotaxis index compared to postoperative samples in patients with pancreatic cancer and healthy volunteers.
Pancreatic ductal adenocarcinoma (PDAC) is among the deadliest diseases, with a five-year survival rate of 9%."
Dr Hideshi Ishii, The Osaka University
Similar to sniffer dogs, the use of Caenorhabditis elegans has been introduced as a new strategy for detecting cancer-associated scents during cancer screening. This biological diagnosis had a reported sensitivity of 95.8%, which was also acceptable even in patients in early-stage of cancer. Furthermore, reports have shown that this test demonstrated high sensitivity in cases of gastrointestinal cancers and negative changes in the postoperative period. Moreover, this test could discriminate urine in a mouse model of pancreatic cancer.
Therefore, this method may be useful for detecting patients with early PDAC. However, how study has yet utilized this method to detect very-early-stage PDAC mainly due to the extreme difficulty of collecting urine samples from such patients. In the present study, they organized a nationwide clinical group that comprised high-volume centers throughout Japan and prospectively collected serum and urine samples from patients with very-early-stage PDAC to investigate the clinical value of a cancer detection system involving C. elegans.
The Ishii Research Team concluded in their Oncotarget Research Output, "the current study observed higher chemotaxis of C. elegans in patients with very-early-stage PDAC, suggesting its potential for use as a standard method for detecting early-stage cancer. Nonetheless, the underlying mechanisms for this chemotaxis should be clarified in order to obtain information that could help elucidate the biological characteristics of cancer."
Asai, A., et al. (2021) Scent test using Caenorhabditis elegans to screen for early-stage pancreatic cancer. Oncotarget. doi.org/10.18632/oncotarget.28035.