Table 1.

COSMIC database search of IDH1 mutation frequencies in various malignancies.

Tissue	Overall IDH1 Mutation Frequency	Frequency of IDH1 R132 Mutations
Central nervous system	6,975/20,299 (34.4%)	6,956/6,975 (99.7%)
Bone	357/1,775 (20.1%)	340/357 (95.2%)
Biliary tract	93/1,097 (8.48%)	91/93 (97.8%)
Pancreas	4/1,712 (0.23%)	2/4* (50%)

^*The 2 R132 mutations were in intraductal papillary neoplasms, while the 2 non-R132 mutations were synonymous variants.