Psoriasis is a chronic, persistent, lifelong disease with a reported point prevalence of 0.8 to 2.8 in the general population.¹ Psoriasis is characterized by scaly, red cutaneous plaques that contain inflammatory infiltrates and epidermal hyperproliferation.² Although psoriasis is not a life-threatening disease, cure is seldom achieved, and its impact on patient health-related quality of life is dramatic.^3-6 The disability experienced by patients with psoriasis is comparable with that of patients with other chronic illnesses, such as heart disease, diabetes mellitus, cancer, and depression.⁷

Background Many studies have investigated the Mediterranean diet as a risk factor for cancer, none of which has included cutaneous melanoma. The latter is usually fatal, rendering knowledge about prevention extremely important. We assessed the role of some food components of the Mediterranean diet and cutaneous melanoma. Methods A hospital-based case–control study was conducted in the inpatient wards of IDI-San Carlo Rome, Italy including 304 incident cases of cutaneous melanoma and 305 controls, frequency matched to cases. Information on socio-demographic characteristics, medical history, smoking, sun exposure, pigmentary characteristics and diet was collected. Logistic regression was the method used to estimated odds ratio and 95% CIs. Results After careful control for several sun exposure and pigmentary characteristics, we found a protective effect for weekly consumption of fish (OR, 0.65, 95%CI = 0.43–0.97), shellfish (OR, 0.53, 95%CI = 0.31–0.89), fish rich in n-3 fatty acids (OR, 0.52, 95%CI = 0.34–0.78), daily tea drinking (OR, 0.42, 95%CI, 0.18–0.95; P_trend = 0.025) and high consumption of vegetables (OR, 0.50, 95%CI = 0.31–0.80, P_trend = 0.005) in particular carrots, cruciferous and leafy vegetables and fruits (OR, 0.54, 95%CI =0.33–0.86, P_trend = 0.013), in particular citrus fruits. No association was found for alcohol consumption and any other food items. Conclusion Overall, our findings suggest that some dietary factors present in the Mediterranean diet might protect from cutaneous melanoma.

Cutaneous melanoma represents the most aggressive form of skin cancer, whereas vitiligo is an autoimmune disorder that leads to progressive destruction of skin melanocytes. However, vitiligo has been associated with cutaneous melanoma since the 1970s. Most of the antigens recognized by the immune system are expressed by both melanoma cells and normal melanocytes, explaining why the autoimmune response against melanocytes that led to vitiligo could be also present in melanoma patients. Leukoderma has been also observed as a side effect of melanoma immunotherapy and has always been associated with a favorable prognosis. In this review, we discuss several characteristics of the immune system responses shared by melanoma and vitiligo patients, as well as the significance of occurrence of leukoderma during immunotherapy, with special attention to check-point inhibitors.