AUA 2018: Exploration of Biomarkers Associated with Prognosis in Patients with Clear Cell Renal Cell Carcinoma Undergoing Surgical Resection by Desorption Electrospray Ionization Imaging Mass Spectrometry

San Francisco, CA USA ( Mr. Keita Tamura, clinical research urology associate from Hamamatsu University School of Medicine, presented data that evaluated the efficacy of a novel molecular anatomy technique, desorption electrospray ionization imaging mass spectrometry (DESI-IMS), to identify biomarkers from a range of lipids from and to predict the prognosis of patients with clear cell renal cell carcinoma (ccRCC). As an introduction, Mr. Tamura stated how although conventional mass spectrometry analysis is widely used to screen small biomolecules, it cannot distinguish between non-cancerous and cancerous tissues and produces false positives.

31 patients with ccRCC undergoing surgical resection were consented for the study. Samples of both non-cancerous and cancerous renal cortex tissues were collected and analyzed with the DESI-IMS in negative ion mode with Xevo G2-XS. Using High Definition Imaging Software and LID MAPS database, Mr. Tamura and colleagues identified ions that exhibited a signal intensity that was 1.5 times higher than the non-cancerous tissue. Following this, they evaluated if the ions had an impact on the overall survival for the 31 patients.

As a result, seven ions of m/z 187.10 (azelaic acid), m/z 279.23 (linoleic acid), m/z 281.25 (oleic acid), m/z 329.25 (docosapentaenoic acid), m/z 389.24 (not assigned), m/z 391.26 (not assigned), and m/z 773.53 (PG (36:2)) were identified as the candidate biomarkers. In regards to overall survival, oleic acid and the unassigned ion of m/z 391.26 had a significant association for the 31 ccRCC patients.

In conclusion, Mr. Tamura and his colleagues identified seven lipid molecules that were evaluated in cancerous renal cortex tissues of ccRCC patients. Following this finding, they found that two of the lipid molecules had a significant impact on overall survival for the ccRCC patients. A future direction they wish to take is to conduct a prospective study with a larger sample size.

With these results, Ms. Bonvillain concluded that there is a potential for clinical translation to non-invasively screen, detect, and diagnose renal masses using urine samples. A future direction their research team proposed was to identify if there are metabolomics differences between different types of renal cancers.

Presented by: Keita Tamura

Written by: Cyrus Lin, Department of Urology, University of California-Irvine at the 2018 AUA Annual Meeting - May 18 - 21, 2018 – San Francisco, CA USA