Nasal alar metastasis of advanced hepatocellular carcinoma misdiagnosed as reactive cutaneous capillary endothelial proliferation in a patient treated with camrelizumab and apatinib: a case report.

Background: Reactive cutaneous capillary endothelial proliferation (RCCEP) is a common adverse event of camrelizumab in the treatment of advanced hepatocellular carcinoma. Facial skin metastasis is an exceptionally uncommon occurrence in hepatocellular carcinoma (HCC). It can be easily mistaken for a prevalent complication known as RCCEP, particularly when it manifests as a persistently enlarging tumor-like mass. This case report highlights a prototypical instance where a metastasis in the nasal alar region of HCC was mistakenly diagnosed as RCCEP during immunotherapy. The findings of this report hold significant clinical value in guiding the management of larger RCCEP lesions encountered during immunotherapy. Case Description: In this case, the patient is a male with a history of hepatitis B. In October 2015, he was diagnosed with HCC. In April 2020, he commenced treatment with ramucirumab (200 mg every 3 weeks) as tumor progression. However, during the third treatment cycle, the patient experienced RCCEP, predominantly affecting the head, neck, trunk, and limbs. To address this, sequential administration of apatinib was initiated, resulting in the gradual regression of RCCEP in these areas. Unfortunately, the metastatic lesion in the nasal alar region continued to grow, exhibiting a tumor-like appearance. On January 25, 2021, surgical resection was performed to remove the nasal alar lesion, and subsequent pathological examination confirmed it as a liver metastasis. Post-surgery, radiation therapy was administered to effectively manage the remaining lesion in the nasal alar region. Importantly, the treatment of the nasal alar metastasis did not hinder the comprehensive management of HCC. The patient obtained excellent curative effect. Conclusions: During the course of immunotherapy for HCC, the emergence of a larger RCCEP lesion that does not show signs of regression even with vigorous treatment raises the suspicion of skin metastasis. It is difficult to distinguish metastatic tumor on the skin from morule- and tumor-like RCCEP that does not easily resolve. To obtain a definitive diagnosis, an early pathological biopsy is crucial. If confirmed as a metastatic tumor, prompt consideration should be given to implementing curative surgical resection.