The potential impact of dietary choices on melanoma risk: an anti-inflammatory diet

The role of inflammation in the aetiology of cancer is recognized. However, no study yet examined the association between an anti-inflammatory diet and cutaneous melanoma and explored whether it could be modified by genetic variations in cyclooxygenase-2 (COX-2), a key enzyme in inflammation. A case-control study was conducted in the IDI-IRCCS hospital in Rome, Italy with 273 cases of primary cutaneous melanoma and 269 controls frequency matched to cases. Information on socio-demographic and pigmentary characteristics, medical history, sun exposure and dietary habits were collected for all subjects. The - 765G > C polymorphism was identified in DNA extracted from blood samples. An anti-inflammatory diet score was created. Logistic regression models were fitted to obtain odds ratios (ORs) and 95% confidence intervals (CIs). A high anti-inflammatory diet score (≥ 8 anti-inflammatory dietary items) was associated with a decreased risk of cutaneous melanoma (OR: 0.29; 95%CI: 0.17-0.49, P_trend < 0.0001) after adjusting for sex, age, education, number of common nevi, skin photo-type, solar lentigines and sunburns in childhood. COX-2 -765 G > C polymorphism was not an independent risk factor for cutaneous melanoma. Although interaction between - 765G > C genotypes and anti-inflammatory diet score was not statistically significant (p = 0.25), when stratified by -765 G > C genotypes the effect of the anti-inflammatory diet was slightly more pronounced for participants carrying - 765GG (OR: 0.17; 95%CI: 0.06-0.47, P_trend < 0.001). Our study findings suggest that adherence to an anti-inflammatory diet is associated with a decreased risk of developing cutaneous melanoma. These results suggest the potential impact of dietary choices on melanoma risk.