Lung cancer is one of the most common causes of cancer worldwide, which was associated with highest treatment cost at $4.2 billion in the United States, and imposing the greatest burden among all cancers in European and other countries. High mortality rate and delayed diagnosis are common for lung cancer patients. Although lung cancer has shown a decreased incidence and mortality in recent decades, it remains the leading cause of related mortality worldwide.The five-year average survival rate is about 15%, which is much lower than that of other cancers, leading to urgent needs to discover more lung cancer-specific biomarkers and reveal its mechanism.

Lung cancer metabolomics database (LCMD) is a freely available online database that covering about 1000 small molecule metabolites described in 55 mass spectrometry-based metabolomics studies related to lung cancer. References are collected through searching the PUBMED with the keywords in title and abstract: (((lung cancer) OR lung adenocarcinoma) AND mass spec*) AND metabol*. But only references that are related to human research were included. Researchers can explore LCMD through ‘’browse metabolites’’ or ‘’browse references’’. Users can get detailed information of each metabolite in the 55 references including specimens, methods, concentrations, statistical results, etc. The external link to HMDB is also supported for more information. Additionally, we created a graphical workflow to summarize each reference for users to overview the study.