Background Melanoma incidence has nearly doubled in the past 2 decades in the Netherlands. It has been debated whether this sharp increase was mainly due to enhanced surveillance and awareness. If this were true then this trend would be even more significant among cancer patients.

Material and Methods Using data from the Netherlands Cancer Registry, we investigated the trend in the risk of developing melanoma among 1 270 815 cancers patients diagnosed between 1989 and 2008. Standardised incidence ratios (SIR) were computed to express melanoma risk among cancer patients as compared with the general population.

Results 4101 patients with a first invasive cancer were subsequently diagnosed with a melanoma. In the first year after diagnosis, risk of being diagnosed with melanoma was more than 10-fold higher among skin cancer patients as compared with the general population (SIR=16.5 95% CI 15.1 to 17.9). The risk dropped to 6.9 (SIR) (95% CI 6.4 to 7.5) 2–5 years post-diagnosis. After non-skin cancer, this drop is much less significant, from SIR=1.6 (95% CI 1.4 to 1.7) to SIR=1.4 (95% CI 1.3 to 1.5) in 0–1 years and 2–5 years after first cancer, respectively. No trend of SIR during the study period was observed.

Discussion and Conclusion Intensive clinical check-up among skin cancer patients may explain the inflated risk of second melanoma, especially in the first year post-diagnosis. Our findings suggest that increased surveillance and awareness were not the sole explanation for the rising incidence of melanoma in the Netherlands.