WHO脑膜瘤分级分型的病理及影像学观察

Pathological classification and iconography of meningiomas

摘要:

目的: 探讨经2007年WHO神经系统肿瘤分类修改后脑膜瘤分级中各级脑膜瘤的病理及影像学特征.方法: 回顾性分析了2007年以来经手术及病理证实的295例脑膜瘤组织病理切片及影像资料.结果: 295例脑膜瘤中WHOⅠ级脑膜瘤255例,Ⅱ级脑膜瘤34例,Ⅲ级脑膜瘤6例.影像学表现:①Ⅰ、Ⅱ、Ⅲ级脑膜瘤肿瘤最大径平均为4.2 cm、4.5 cm及4.6 cm.②Ⅰ级脑膜瘤多为类球形,Ⅱ级脑膜瘤中分叶状比率高于Ⅰ级,Ⅲ级大部分为分叶状.③Ⅰ、Ⅱ、Ⅲ级脑膜瘤边界不清者所占比率为23.9%、55.8%及100%.④硬膜尾征在Ⅰ、Ⅱ、Ⅲ级脑膜瘤中发生率为67.8%、55.9%及66.6%.⑤Ⅰ、Ⅱ、Ⅲ级脑膜瘤均有不同程度的周边组织侵润.随访152例,8例复发,其中Ⅰ级1例、Ⅱ级4例、Ⅲ级3例.结论: 脑膜瘤以Ⅰ级脑膜瘤多见,其中纤维型、上皮型、过渡型较常见,而分泌性、化生型、微囊型及淋巴细胞丰富型少见;Ⅱ级脑膜瘤以非典型性脑膜瘤居多,透明细胞型、脊索样型少见,且均有不同程度的核分裂像;Ⅲ级脑膜瘤少见,呈明显恶性性生长方式且均有明显的核分裂像及坏死区.Ⅰ、Ⅱ、Ⅲ级脑膜瘤肿瘤直径及硬膜尾征无明显差异性,Ⅱ、Ⅲ级脑膜瘤分叶状比率较Ⅰ级高,且边界多不清,各级脑膜瘤均表现为不同程度的侵袭性生长.术后复发率与脑膜瘤分级有关.

Abstract:

Objective: To investigate the pathological classification and iconography of meningiomas.Methods: We retrospectively studied the pathological section and imaging features of 295 cases meningiomas which were corroborative by pathological diagnosis.Results: The WHO grade Ⅰ meningiomas were 255 cases,grade Ⅱ meningiomas were 34 cases and grade Ⅲ were 6 cases.Imaging manifestations:The mean diameter of WHO grade Ⅰ,Ⅱ and Ⅲ meningiomas were 4.2 cm,4.5 cm and 4.6 cm respectively.The shapes of WHO grade I meningiomas were predominantly rounded.The rate of lobular shape of WHO grade Ⅱ meningiomas was higher than that of WHO grade Ⅰ meningiomas.While most of the shapes of WHO grade Ⅲ meningiomas was lobular.There were 23.9% WHO grade Ⅰ,55.8% WHO grade Ⅱ and 100% WHO grade Ⅲ meningiomas with unclear boundaries.Dural tail could be found in about 67.8% WHO grade Ⅰ,55.9% WHO grade Ⅱ and 66.6% WHO grade Ⅲ meningiomas.WHO grade Ⅰ,Ⅱ and Ⅲ meningiomas had various invasion of peripheral tissue.During the 2-5 years follow-up,8 cases were recurrence in the total 152 cases.Conclusions: Most of these meningiomas are grade I which included the common fibrous meningioma,meningothelial meningioma and transitional meningioma,and the rare type of secretory meningioma,microcysticm meningioma,metaplastic meningioma,lymphoplasmacyte-rich meningioma.The majority of grade Ⅱ meningiomas are atypical meningioma,the few are clear cell meningioma and chordoid meningioma.The grade Ⅲ meningiomas are rare which showed a malignant growth pattern and have obvious mitosis and necrosis.There is no significant difference in tumor diameter and dural tail.The rates of lobular shape and unclear boundary of WHO grade Ⅱ and Ⅲ meningiomas are higher than that of WHO grade Ⅰ meningiomas.Most of the tumors show invasive growth among the grade Ⅰ、Ⅱ、Ⅲ.The postoperative recurrence rate is related to meningioma grading.