Abstract：
Alveolar rhabdomyosarcoma is a common malignant soft tissue tumor in child and adolescents. Intracranial alveolar rhabdomyosarcoma in adults is rare, especially in the pineal region. We present a case of primary alveolar rhabdomyosarcoma of the pineal gland in a 36-year-old Chinese male with a chief complaint of dizziness, headache and a loss of balance when walking. Imaging identified a space-occupying mass in the pineal region with obstructive hydrocephalus. An endoscopic-assisted pineal mass resection was performed. Pathology revealed a solid, sheet-like growth of medium-sized, round or oval cells with map-like necrosis and some rhabdomyoblasts. The tumor cells were diffusely positive for desmin, myogenin, MyoD1, ALK, and OLIG2. Fluorescence in situ hybridization (FISH) detected FOXO1 gene rearrangement. This rare case is presented to expand the knowledge of pineal gland tumors and alert us to pay attention to the differential diagnosis of OLIG2-positive round-cell tumors of the central nervous system.
摘要：
肺泡横纹肌肉瘤是儿童和青少年常见的恶性软组织肿瘤。成人颅内肺泡横纹肌肉瘤很少见，尤其是松果体区.我们介绍了一名36岁的中国男性的松果体原发性肺泡横纹肌肉瘤，主要表现为头晕，走路时头痛和失去平衡。成像发现松果体区域有一个占位肿块，伴有梗阻性脑积水。进行了内窥镜辅助的松果体肿块切除术。病理学显示，中等大小的片状生长，圆形或卵圆形细胞，有地图样坏死和一些横纹肌母细胞。肿瘤细胞结蛋白呈弥漫性阳性，Myogenin,MyoD1,ALK,和OLIG2。荧光原位杂交(FISH)检测FOXO1基因重排。此罕见病例旨在扩大对松果体肿瘤的认识，并提醒我们注意中枢神经系统OLIG2阳性圆形细胞肿瘤的鉴别诊断。
