Department of Behavioral Neuroscience, University of San Diego, San Diego, CA.
Kaiser Permanente Riverside Medical Center, Riverside, CA.
Perm J. 2021 May;25. doi: 10.7812/TPP/20.235.
Merkel cell carcinoma (MCC) is a rare and aggressive neuroendocrine cancer with a high mortality rate of 33% to 46%. Merkel cell is a type of epidermis cell receptor responsible for contact sensitivity and is known to have neuroendocrine properties. Treatment of Merkel cell carcinoma with avelumab has been prominsing, but its rarity and poor prognosis necessitates close follow up.
A 71-year-old woman presented with a left forearm mass that was initially suspected to be a sebaceous cyst. After surgical excision and biopsy, she was diagnosed with Merkel cell carcinoma. The patient underwent avelumab treatment for 2 years, with remission of cancer for 24 months. A positron emission tomographic scan at 24 months of treatment noted uptake in the left axilla and portocaval regions. Despite receiving different combinations of immunotherapy, chemotherapy, and radiation, the patient's cancer metastasized to the leptomeninges. She was transitioned to hospice and passed away 3 months after diagnosis of leptomeningeal carcinoma.
This case highlights the efficacy of avelumab in keeping patients in remission, which can offer increased quality of life. However, it also highlights the aggressive nature of Merkel cell carcinoma and the importance of surveillance for early detection of recurrence.
默克尔细胞癌（Merkel cell carcinoma，MCC）是一种罕见且侵袭性的神经内分泌癌，死亡率高达 33%至 46%。默克尔细胞是一种表皮细胞受体，负责接触敏感性，已知具有神经内分泌特性。avelumab 治疗默克尔细胞癌的效果显著，但由于其罕见性和预后不良，需要密切随访。
一名 71 岁女性因左前臂肿块就诊，最初怀疑为皮脂囊肿。经手术切除和活检后，被诊断为默克尔细胞癌。患者接受了avelumab 治疗 2 年，癌症缓解了 24 个月。治疗 24 个月时的正电子发射断层扫描（PET）显示左腋窝和门腔区域有摄取。尽管接受了不同组合的免疫疗法、化疗和放疗，但患者的癌症转移到了软脑膜。她转入临终关怀，在诊断为软脑膜癌后 3 个月去世。
本病例强调了avelumab 使患者缓解的疗效，这可以提高生活质量。然而，它也突出了默克尔细胞癌的侵袭性和早期发现复发的重要性。
