Prolonged Remission of Cancer of Unknown Primary following Initiation of Eculizumab Therapy for Paroxysmal Nocturnal Hemoglobinuria

Figure 2

Lymph node biopsy. The malignant cells are strongly positive with antibodies to cytokeratin, indicating epithelial lineage and supporting the diagnosis of carcinoma (cytokeratin AE1/AE3, 200x).