Conflict of interest: the authors declare that they have no conflicts of interest. The recent publication by van der Geer et al.1 concludes that ‘the number of nonmelanoma skin cancers (NMSCs) differs substantially in practice from the number of first primary histologically confirmed NMSCs, as usually reported by population‐based cancer registries such as the Eindhoven Cancer Registry (ECR)'. We fully agree with this unsurprising conclusion, as designation of ‘first primary’ implies that there may be more tumours, and it is well known that a substantial proportion of patients with basal cell carcinoma (BCC) develop one or more subsequent BCCs, depending on age at first diagnosis and intensity of surveillance.2,3,4,5 However, we disagree with the methodology and with the negative interpretation of work by population‐based registries. The random sample of patients with skin cancer studied by van der Geer et al.1 was treated in a highly specialized dermatology clinic, as illustrated by the reported high proportion of patients treated with Mohs micrographic surgery. In such a population, the proportion of patients with high‐risk BCC who develop multiple primaries is most likely much higher than in the general BCC population. The authors failed to adequately specify the characteristics of the population, and patient selection was unclear, and included first and subsequent skin cancers. In addition, the study combined all skin cancers for the estimation of the percentage of patients with multiple skin cancers over time, whereas risk of subsequent malignancies differs substantially for the different types of skin cancer.4