Risk of subsequent primary malignancies among patients with Merkel cell carcinoma

The risk of subsequent primary malignancies after a diagnosis of cutaneous Merkel cell carcinoma (MCC) is not well established. A cohort study using data from 17 registries of the SEER program from 2000 to 2018 found that among 6146 patients with a first primary cutaneous MCC diagnosis, there was an increased risk of developing subsequent primary cancers, including solid tumors such as papillary thyroid carcinoma and melanoma, and hematologic cancers such as non-Hodgkin lymphoma. The authors conclude that the findings of this study suggest that patients with MCC have an increased risk of subsequent cancers. Further studies exploring common etiological factors shared between MCC and other primary cancers are warranted.