Table 1

SMARCB1 mutations in key tumours

Cancer typeLoss of SMARCB1 expression (%)Genetic alteration in SMARCB1
Malignant rhabdoid tumour100Biallelic inactivation (whole-gene deletions, large intragenic deletions/duplications, insertions, splice-site mutations and nonsense mutations)
Epithelioid sarcoma80–90Homozygous deletions
Renal medullary carcinoma100Loss of heterozygosity at SMARCB1 locus
Medullary carcinoma40 paediatric
10 adults
Malignant peripheral nerve sheath tumour50Unknown
Extraskeletal myxoid chondrosarcoma17Truncating mutations in both alleles of SMARCB1; homozygous deletions or microdeletions
Familial schwannomatosis45*Non-truncating splice-site mutations and missense mutations in exon 1
  • *Immunohistochemistry demonstrates a mosaic pattern with scattered immunopositive cells interspersed with immunonegative cells (majority of tumour cells).