Cutaneous Melanoma More Likely to Be Invasive in Fairer Skin Phototypes: A Retrospective Observational Study.

Fitzpatrick skin phototype is one of the factors determining melanoma development, with fairer skin phototypes I and II known to be associated with a higher risk. This study aimed to identify any associations between skin phototype and the histologic subtype, Breslow's thickness, and the site of melanoma. Patients diagnosed with melanoma for over an 18-month period were included. Data were gathered from the Malta National Cancer Registry. There were 167 registered cutaneous melanoma patients, of which 135 were included in the study. Melanomas in patients with skin phototypes I and II were more likely to be invasive than in situ when compared to patients with skin phototypes III and IV ( P = 0.00027). There was also an association between skin phototype and histologic type of melanoma ( P = 0.005), with melanoma in situ being the most common subtype in patients with skin type III. This study confirms that fairer skin phototypes have an increased risk of melanoma. It also shows that in our population, melanoma in skin phototypes I and II is more likely to be invasive rather than in situ compared to melanoma in darker skin phototypes. Further studies are required to confirm these findings and identify possible reasons.