A Systematic Review of the Histopathology and Immunochemistry in Duodenal Gangliocytic Paragangliomas with Lymph Node Metastases to Identify Predictors of Malignancy

Gangliocytic paragangliomas (GP) are rare tumors, most commonly located in the 2nd portion of the duodenum.Their origin is poorly understood and management is uncertain.Typically exhibiting benign behavior, they infrequently metastasize to lymph nodes (LN) and distant sites.Due to their triphasic cellular distribution, tissue diagnosis pre-operatively remains a challenge, as well as prediction of which tumors may metastasize or act more aggressively.A systematic literature search was performed, and data for epidemiology, clinical history, gross pathology, and histopathology of duodenal (DGPs) with LN metastases was collected.Histopathology and Immunohistochemistry (IHC) was described and compared to a review by Okubo et al in an effort to identify predictors of malignancy.It is difficult to obtain a tissue diagnosis and predict malignant behavior of DGPs.Increased tumor size, depth of invasion, angio-lymphatic invasion and IHC findings may warrant further investigation for LN metastases.The presence of LN metastases does not seem to influence the prognosis, but rather the treatment modality.