Aggressive CD8(+) epidermotropic cutaneous T-cell lymphoma associated with homozygous mutation in SAMHD1.

Mutations in the SAMHD1 (SAM domain and HD domain–containing protein 1) gene are implicated in SAMS (stroke, aneurysm, moyamoya, and stenosis) association,1, 2 also described as Aicardi-Goutieres syndrome type 5 (AGS-5).3 We present a patient with homozygous germline mutations in SAMHD1 who subsequently had a CD8+ aggressive epidermotropic cutaneous T-cell lymphoma (CTCL).