Co-existence of psoriasis and cutaneous T-cell lymphoma.

It has been reported that individuals with psoriasis are at an increased risk of developing cutaneous T-cell lymphoma (CTCL). However, the increased risk of lymphoma in these patients has been questioned because CTCL in its early stages may be incorrectly labelled as psoriasis, thus introducing potential for misclassification bias. We retrospectively reviewed patients with a confirmed diagnosis of CTCL seen in a tertiary cutaneous lymphoma clinic (n = 115) over a 5-year period and found that 6 (5.2%) patients had clinical evidence of co-existing psoriasis. This demonstrates that there is a small cohort of individuals who develop both psoriasis and CTCL.