Dorsal Root Ganglion

The dorsal root ganglia consist of the cell bodies of sensory afferent neurons and are located along either side of the spinal cord. These unipolar neurons characteristically have large cell bodies, which are needed to support the very long axons that carry sensory information from the distal extremities to the cord. Normal ganglia (such as the one depicted here) can occasionally have binucleated cells that may be misinterpreted as neoplastic change. Neurons in the dorsal root ganglia manifest the prototypical ganglioid appearance, characterized by a large cell body with ample-to-abundant cytoplasm and an oval nucleus with prominent nucleolus. Ganglioid differentiation can be seen in many CNS and PNS neoplasms, at times making it difficult to distinguish a tumor with intrinsic ganglioid differentiation (e.g. ganglioneuroma) from a tumor that is involving an otherwise normal dorsal root ganglion (as was the case for this patient). Normal ganglion cells are typically surrounded by thin, flattened satellite cells that separate them from the adjacent tissue, whereas abnormal ganglion/ganglioid cells are often intimately embedded within the neoplastic stroma and lack satellite cells.