Abstract
Subcutaneous metastasis of endometrial cancer (EC) is an exceedingly rare phenomenon, and the mechanisms underlying its pathogenesis remain insufficiently elucidated. We report the case of a 69-year-old multiparous woman diagnosed with stage IB EC, histologically classified as grade 3 endometrioid and clear cell carcinoma. Approximately one month following primary surgical intervention, the patient developed subcutaneous masses on her back, axilla, and buttock. Histopathological evaluation, in conjunction with PET-CT, confirmed a systemic recurrence of EC. She was subsequently treated with a combination of paclitaxel and carboplatin, with a remarkable therapeutic response; after six cycles of chemotherapy, nearly all metastatic sites exhibited complete resolution. She was then transitioned to a regimen of lenvatinib and pembrolizumab. However, one week after the initiation of this treatment, she developed hepatic encephalopathy, which was presumed to be lenvatinib-induced, and was successfully managed with aminoleban injections, resulting in a full recovery of consciousness. Follow-up diagnostic imaging confirmed a complete response to therapy. The patient is currently receiving pembrolizumab as maintenance therapy and has remained recurrence-free for 18 months. While no standardized therapeutic protocol exists for the management of subcutaneous metastasis in EC due to its extremely low incidence, this report provides evidence for the potential efficacy of chemotherapy combined with targeted immunotherapy in the treatment of unresectable subcutaneous metastases in EC.