Malignant gastrointestinal neuroectodermal tumor (M-GNET) and clear cell sarcoma (CCS) of soft tissue represent closely related, extremely rare, malignant mesenchymal neoplasm of uncertain differentiation. Both entities are characterized genetically by the same molecular alterations represented by the presence of EWSR1-ATF1 and, more rarely, EWSR1-CREB1 fusion genes. The latter translocation seems to be more represented in M-GNET that, despite significant morphologic overlap with CCS, tends to lack overt features of melanocytic differentiation. Most M-GNET occur in the lower gastrointestinal tract, whereas occurrence in the upper tract has been reported only exceptionally. The differential diagnosis represents a major challenge, and accurate diagnosis impact significantly on therapeutic planning. We herein report the clinicopathologic features of a molecularly confirmed M-GNET that arose at the base of the tongue and review the pertinent literature.

恶性胃肠神经外胚层肿瘤（M-GNET）和软组织透明细胞肉瘤（CCS）代表着密切相关的，极为罕见的恶性间充质恶性肿瘤。两个实体都通过的存在表示的相同的分子改变遗传特征EWSR1 - ATF1，更很少，EWSR1，CREB1融合基因。后者的易位似乎在M-GNET中表现得更多，尽管与CCS在形态上有明显的重叠，但往往缺乏黑素细胞分化的明显特征。大多数M-GNET发生在下消化道，而仅在例外情况下报告在上消化道。鉴别诊断是一个重大挑战，准确的诊断对治疗计划有重大影响。我们在这里报告出现在舌根的分子确认的M-GNET的临床病理特征，并复习相关文献。