Thoracic Spinal Metastasis of Merkel Cell Carcinoma in an Immunocompromised Patient: Case Report

Study Design Case report. Objective Merkel cell carcinoma (MCC), an uncommon cutaneous neuroendocrine malignancy, is a rare cause of spinal metastasis, with only five cases previously reported. We report a rare case of MCC metastatic to the spine in an immunocompromised patient. Methods A 55-year-old male with previously resected MCC, immunocompromised due to cardiac transplant, presented with sharp mid-thoracic back pain radiating around the trunk to the midline. Computed tomography of the thoracic spine showed a dorsal epidural mass from T6 to T8 with compression of the spinal cord. Laminectomy and subtotal tumor resection were performed, and pathology confirmed Merkel cell tumor through immunohistochemistry staining positive for cytokeratin 20 and negative for thyroid transcription factor-1. Results Further treatment with radiation therapy was initiated, and the patient did well for 4 months after surgery, but returned with a lesion in the cervical spine. He then opted for hospice care. Conclusions With an increasing number of immunocompromised patients presenting with back pain, MCC should be considered in the differential diagnosis of spinal metastatic disease.