Introduction: Merkel cell carcinoma (MCC) is a rare cutaneous malignancy of neuroendocrine origin with an incidence of 0.7 per 100,000 persons, with about 30 cases of brain metastasis (BM) reported in the literature. Historically, the treatment of metastatic MCC has been chemotherapy (CT) and radiotherapy (RT) to nodal or metastatic disease. While the treatment of MCC is evolving, the role for surgical resection of BM remains not well established.
Methods: We surveyed institutional databases (BWH & MGH) to identify patients with MCC BMs. Clinical information was extracted by chart review. Additionally, a systematic review of the literature was conducted for cases reporting on management and survival of distant MCC BM. A pooled analysis was performed for outcomes in BM patients managed operatively versus non-operatively.
Results: A total of 13 patients between 2004-2017 were identified, of which seven patients underwent resection of 1 BM. 27 cases of MCC BM were identified in the literature, describing operative (7) and non-operative (20) management. Pooling institutional and literature cases, the age at MCC diagnosis and time to CNS involvement was 65±10-years and 17-months (11-27), respectively, with no significant difference between the groups. Patients managed non-operatively had more extensive intracranial burden of disease (BoD) but similar systemic BoD, compared to those managed operatively. Non-operative and adjuvant therapy included radiotherapy, CT and/or immunotherapy. Median survival was 73- and 25-months (95% CI 31-115, 14-36) in the operative group and non-operative group, respectively. On univariate analysis, having a single BM and undergoing neurosurgical resection were each associated with a survival benefit. When controlling for other clinical factors, surgical resection conferred a survival benefit compared to non-operative management (HR 0.09, 95%CI 0.02-0.042, p=0.002).
Conclusions: In patients who are candidates for surgery, resection of MCC BM confers an overall survival benefit relative to non-operative management and should therefore be considered.
Patient Care: This work will hopefully make clinicians more aware of MCC as a pathological entity, and more likely to offer neurosurgical intervention to patients with MCC BM.
Learning Objectives: 1) Describe the origin of merkel cell carcinoma (MCC)
2) Describe the treatment modalities for neuro-mestastatic