Complete remission of reactive cutaneous capillary endothelial proliferation caused by the programmed cell death-1 inhibitor camrelizumab achieved through thalidomide monotherapy: A case report.

Reactive cutaneous capillary endothelial proliferation (RCCEP) is a common adverse effect of the anti-programmed cell death-1 (PD-1) monoclonal antibody camrelizumab and usually occurs on the skin. This condition causes bleeding nodules of varying severity depending on disease grade; these affect a person's appearance and quality of life. The exact mechanism remains elusive and its occurrence in visceral organs has not been previously reported, to the best of our knowledge. Furthermore, there is currently a lack of standard, uniform treatments. The present study reported on a patient who experienced RCCEP during treatment with camrelizumab and benefited greatly from thalidomide, which caused no serious adverse events. An elderly Chinese female initially diagnosed with stage II endometrial cancer had previously undergone surgery, radiotherapy and intravenous chemotherapy but developed multiple metastases in the peritoneum and vaginal remnant. The patient was subsequently prescribed camrelizumab after systemic treatment failed. Soon after commencing treatment with this PD-1 inhibitor, the patient developed RCCEP, whereupon oral low-dose thalidomide monotherapy (100 mg nightly) was prescribed. At two weeks after commencing thalidomide, the RCCEP symptoms were alleviated. Based on this patient's successful treatment, it is suggested that low-dose thalidomide may be an alternative intervention for patients with camrelizumab-induced RCCEP.