JAAD online

Rapidly progressive malignant melanoma in a patient treated with tocilizumab

Few data exist on the relationship between psoriasis and melanocytic lesions.

We sought to investigate number of melanocytic nevi in psoriatic patients compared with control subjects and its relationship with disease severity and treatment.

We performed a prospective study in 189 psoriatic patients and 189 control subjects. Sociodemographic and clinical data were recorded for all participants.

As compared with control subjects, patients had fewer nevi overall [χ²(5) = 52.24, P < .001], fewer nevi less than 5 mm [χ²(4) = 60.28, P < .001], and fewer congenital nevi [χ²(1) = 10.41, P = .002]; no differences in atypical nevi and family history of cancer, including melanoma, were observed. Among psoriatic patients, number of biologics used was a risk factor for a higher nevus count [odds ratio 1.35 (95% CI 1.04-1.76), P = .02] whereas disease severity did not correlate with number of nevi.

Low number of psoriatic patients naïve to systemic therapies was a limitation.

Psoriatic patients have fewer nevi than control subjects. Frequency of nevi in psoriatic patients is related to treatment, not to disease severity.