Abstract：
BACKGROUND: Papillary intralymphatic angioendothelioma (PILA) is an exceptionally rare metastasizing soft tissue tumor. It tends to arise in the subcutaneous tissues of distal extremities in children. Only four intraosseous PILA cases have been reported until now in English language literature.
METHODS: We present a case of PILA arising in the distal femoral epiphysis of a 50-year-old female patient. It started as a relentless pain in her left knee. A plain radiography revealed a radiolucent area in the left internal femoral condyle. Computerized tomography revealed a 1-cm lytic lesion with a sclerotic rim. Magnetic resonance images showed a significant bone marrow edema signal focused on a 1-cm subchondral lesion suggestive of an intraarticular osteoid osteoma. Histologically, the tumor contained vascular channels covered by a single endothelial layer with intraluminal papillary endothelial structures lined with hobnail cells. Immunohistochemically, the cells were positive for ERG, CD31, and D2-40. The tumor underwent cryoablation and 6 months later, after local recurrence or tumor persistence, a wide tumor resection was referred. After 7 years of follow-up, the patient displayed neither local recurrence nor distant metastases.
CONCLUSIONS: Primary intraosseous PILAs are exceedingly rare tumors that should be considered in the differential diagnosis of vascular bone tumors.
METHODS: We present a case of PILA arising in the distal femoral epiphysis of a 50-year-old female patient. It started as a relentless pain in her left knee. A plain radiography revealed a radiolucent area in the left internal femoral condyle. Computerized tomography revealed a 1-cm lytic lesion with a sclerotic rim. Magnetic resonance images showed a significant bone marrow edema signal focused on a 1-cm subchondral lesion suggestive of an intraarticular osteoid osteoma. Histologically, the tumor contained vascular channels covered by a single endothelial layer with intraluminal papillary endothelial structures lined with hobnail cells. Immunohistochemically, the cells were positive for ERG, CD31, and D2-40. The tumor underwent cryoablation and 6 months later, after local recurrence or tumor persistence, a wide tumor resection was referred. After 7 years of follow-up, the patient displayed neither local recurrence nor distant metastases.
CONCLUSIONS: Primary intraosseous PILAs are exceedingly rare tumors that should be considered in the differential diagnosis of vascular bone tumors.
摘要：
背景：乳头状淋巴管内血管内皮瘤（PILA）是一种极为罕见的转移性软组织肿瘤。它往往出现在儿童四肢远端的皮下组织中。到目前为止，英语文献中仅报告了4例骨内PILA病例。
方法：我们介绍了一例50岁女性患者股骨远端骨phy中出现PILA的病例。它开始于她的左膝盖无情的疼痛。X线平片显示左股骨内髁有射线可透区域。计算机断层扫描显示1厘米的溶解性病变，带有硬化边缘。磁共振图像显示明显的骨髓水肿信号集中在1厘米的软骨下病变上，提示关节内骨样骨瘤。组织学上,肿瘤包含由单个内皮层覆盖的血管通道，管腔内乳头状内皮结构衬有hobnail细胞。免疫组织化学，细胞ERG呈阳性,CD31和D2-40。肿瘤进行冷冻消融，6个月后，在局部复发或肿瘤持续存在后，进行了广泛的肿瘤切除。经过7年的随访，患者既无局部复发也无远处转移.
结论：原发性骨内PILA是非常罕见的肿瘤，在血管骨肿瘤的鉴别诊断中应考虑。
方法：我们介绍了一例50岁女性患者股骨远端骨phy中出现PILA的病例。它开始于她的左膝盖无情的疼痛。X线平片显示左股骨内髁有射线可透区域。计算机断层扫描显示1厘米的溶解性病变，带有硬化边缘。磁共振图像显示明显的骨髓水肿信号集中在1厘米的软骨下病变上，提示关节内骨样骨瘤。组织学上,肿瘤包含由单个内皮层覆盖的血管通道，管腔内乳头状内皮结构衬有hobnail细胞。免疫组织化学，细胞ERG呈阳性,CD31和D2-40。肿瘤进行冷冻消融，6个月后，在局部复发或肿瘤持续存在后，进行了广泛的肿瘤切除。经过7年的随访，患者既无局部复发也无远处转移.
结论：原发性骨内PILA是非常罕见的肿瘤，在血管骨肿瘤的鉴别诊断中应考虑。
