神经纤维瘤病型与非神经纤维瘤病型先天性胫骨假关节组织对比研究

Histological comparison of periosteum in congenital tibial pseudarthrosis with and without neurofibromatosis type 1

目的比较先天性胫骨假关节(congenital pseudarthrosis of the tibia,CPT)合并神经纤维瘤病Ⅰ型(neurofibromatosis type 1,NF1)和CPT不合并NF1病变骨膜的组织病理特点有无差异。方法收集2016年9月至2020年12月在湖南省儿童医院骨科接受治疗的CPT合并NF1患儿20例(NF1-CPT组)、CPT不合并NF1患儿20例(非NF1-CPT组)病变骨膜标本,收集2021年12月至2021年1月接受手术治疗的5例脑瘫患儿胫骨骨膜标本(对照组)。首先观察标本的大体形态学特点;然后对组织切片进行苏木精-伊红染色,描述组织形态学特点,并计算平均血管密度;最后对组织切片进行CD34、蛋白基因产物9.5(protein gene product 9.5,PGP9.5)和增殖细胞核抗原(proliferating cell nucelar antigen,PCNA)的免疫组织化学染色,比较CD34、PGP9.5、PCNA在各组阳性表达的差异。结果NF1-CPT组和非NF1-CPT组病变骨膜的大体形态学特点基本一致,均表现为病变骨膜明显增厚,胫骨萎缩、变尖,髓腔闭塞,胫骨假关节形成;组织形态学特点也基本一致,均由大量高分化的成纤维细胞和增生的胶原纤维构成。NF1-CPT组和非NF1-CPT组病变骨膜伴有局部血管增生,增生血管的管壁增厚,管腔十分狭窄呈裂隙状,甚至趋向闭塞。NF1-CPT组、非NF1-CPT组、对照组间平均血管密度(mean vessel density,MVD)均无统计学差异(P>0.05);NF1-CPT组、非NF1-CPT组、对照组CD34阳性表达部位的平均光密度(mean optical density,MOD)差异均无统计学意义(P>0.05)。病变骨膜中存在神经纤维组织,但无异常神经纤维增生。NF1-CPT组和对照组、非NF1-CPT组和对照组PGP9.5阳性表达部位的MOD,分别为0.063(0.032,0.099)比0.226(0.129,0.389)、0.063(0.040,0.085)比0.226(0.129,0.389),差异均具有统计学意义(P<0.05)。NF1-CPT组和非NF1-CPT组、NF1-CPT组和对照组、非NF1-CPT组和对照组PCNA半定量分析结果差异均具有统计学意义(P<0.05)。结论CPT合并NF1患儿和CPT不合并NF1患儿病变骨膜在大体形态学、组织形态学特征以及血管、神经的组织病理学特点等方面无明显差异,增殖活性存在差异。

Objective To compare the histopathological characteristics of periosteum between congenital pseudarthrosis of tibia(CPT)with neurofibromatosis type 1(NF1)and CPT without NF1.Methods From September 2016 to December 2020,periosteal specimens of the lesions were collected from 20 children with CPT&NF1(NF1-CPT group)and another 20 without CPT&NF1(non-NF1-CPT group).And tibial periosteal specimens were harvested from five surgical children with cerebral palsy from December 2021 to January 2021(control group).Gross morphological characteristics of specimens were observed.Then hematoxylin-eosin stain was performed on tissue sections for observing the histomorphological characteristics and calculating mean vascular density.Finally immunohistochemical stain of CD34,protein gene product 9.5(PGP9.5)and proliferating cell nuclear antigen(PCNA)was performed on tissue sections for comparing the differences in positive expression of CD34,PGP9.5 and PCNA in each group.Results Gross morphological characteristics of diseased periosteum were basically the same in NF1-CPT and non-NF1-CPT groups.There were marked thickening of diseased periosteum,tibial atrophy and sharpening,medullary cavity occlusion and tibial pseudarthrosis formation.Histomorphological characteristics remained basically the same.There were numerous well-differentiated fibroblasts and proliferating collagen fibers.The periosteum of both groups was accompanied by local vascular proliferation,wall of hyperplastic vessels thickened and lumen narrowed slit-like or even became occluded.No statistically significant differences existed in mean vessel density(MVD)among NF1-CPT,non-NF1-CPT and control groups(P>0.05).No statistically significant differences existed in mean optical density(MOD)of CD34-positive expression sites among NF1-CPT,non-NF1-CPT,and control groups(P>0.05).Nerve fiber tissue was present in periosteum of lesion.However,there was no abnormal nerve fiber proliferation.The MODs of PGP9.5 positive expression sites in NF1-CPT and control groups,non-NF1-CPT and control groups were 0.063(0.032,0.099)vs.0.226(0.129,0.389),0.063(0.040,0.085)vs.0.226(0.129,0.389)respectively and the differences were statistically significant(P<0.05).Significant differences existed in semiquantitative analytic results of PCNA between NF1-CPT and non-NF1-CPT,NF1-CPT and control and non-NF1-CPT and control groups(P<0.05).Conclusions No significant differences exist in gross morphology,histomorphological features and histopathological features of blood vessels and nerves between diseased periosteum of children with CPT&NF1 and those without CPT.And there were differences in proliferative activity.