Lichen planus carries a site-specific cancer risk, and fertility treatment's melanoma signal stays small and uncertain

The edition in brief

In 35,845 people with lichen planus in Danish registers, the risk of oral cavity cancer was about seven times the general population's (SIR 7.5 in women) and vulvar cancer about two and a half times, with the excess concentrated at the site of the lichen planus. Absolute 20-year risks stayed low, about 1% for oral cavity cancer, so the finding supports targeted long-term review of affected mucosa rather than alarm. A meta-analysis of 12 observational studies covering 3.7 million women found fertility treatment associated with a modest rise in melanoma risk (HR 1.24), stronger with drug-only ovulation induction and near-null with IVF, but certainty was very low to low and ultraviolet exposure was poorly adjusted; the authors say practice should not change. A telehealth trial in 364 families of melanoma survivors improved children's sun-protective behaviour but did not reduce sunburn over time. The pearl covers practical sun protection advice for high-risk children.