Oncology Letters is indexed and/or abstracted in:

• PubMed (NLM)
• PubMed Central
• Biological Abstracts® (Clarivate Analytics)
• BIOSIS Previews®(Clarivate Analytics)
• Chemical Abstracts Service (CAS)
• EMBASE (Elsevier)
• Google Scholar
• Index Copernicus (IC)
• Science Citation Index Expanded®(Clarivate Analytics)
• Scopus (Elsevier)
• CNKI Scholar
• Ingentaconnect
• Ex Libris
• OCLC (WorldCat Local and WorldCat.org)
• Academic OneFile (Cengage)
• EBSCO Host
• Academic Search Complete
• EBSCO Discovery Service
• Ovid
• Medline Complete
• ISLIB
• Proquest - Summon Database