Lipid profiles for intrahepatic cholangiocarcinoma identified using matrix-assisted laser desorption/ionization mass spectrometry.

BACKGROUND

We evaluated whether direct tissue matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) analysis of lipids may distinguish intrahepatic cholangiocarcinomas from adjacent normal tissue and from other adenocarcinomas that frequently metastasize to liver.

METHODS

Four pairs of frozen surgical specimens of cholangiocarcinomas and adjacent normal tissue were analyzed using histology-directed, MALDI MS analysis. 2,5-dihydroxybenzoic acid / α-cyano-4-hydroxycinnamic acid were manually deposited on tumor-rich areas, and mass spectra were acquired using a MALDI-time of flight instrument.

RESULTS

Cholangiocarcinomas and adjacent normal tissue samples demonstrated different lipid profiles, as evidenced by permutation P value<0.05 for the cross-validated misclassification rate. Cancer-associated lipid alteration was similar between cholangiocarcinomas and pancreatic cancers, but not between cholangiocarcinomas and colorectal cancers. Baseline lipid profiles were different between cholangiocarcinoma and colorectal cancers.

CONCLUSIONS

MALDI MS analysis of lipid distinguishes cancerous epithelium of cholangiocarcinoma from adjacent normal tissue, and between cholangiocarcinomas and colorectal cancers.