甲状腺乳头状癌诊断性核特征的量化评价

摘要

目的 探讨量化评价甲状腺乳头状癌(papillary thyroid carcinoma,PTC)诊断性核特征(核沟、核重叠、毛玻璃样核及核内假包涵体)的可行性,并分析诊断PTC所需核特征的可能阈值.方法 通过对80例PTC的再观察,根据其核特征的分布与分级状况,半定量评价为3组,即核特征高、中、低水平表达组.结果 (1)88%(70/80)的病例同时表达4项核特征,12%(10/80)的病例呈3项核特征,无病例仅出现2项或以下核特征.(2)80例PTC中,核特征高水平表达组16例(20%,16/80);中水平表达组59例(74%,59/80);低水平表达组5例(6%,5/80).分布趋势为正偏态分布.(3)组织学亚型上,高水平表达组包括经典型与微小癌两类;中水平组涵盖经典型、微小癌、滤泡型、高细胞型、嗜酸细胞型、透明细胞型、实体型及筛状癌8种亚型;低水平表达组由经典型、实体型及弥漫硬化型构成.(4)80例PTC中,非浸润性PTC 8例(10%,8/80),形态学均表现为包裹性经典型PTC.非浸润性PTC在高、中、低表达组内的构成比依次为:19%(3/16)、8%(5/59)、0(0/5).结论 (1)诊断PTC,应要求病变内至少具备3项诊断性核特征.(2)多数PTC的核特征,为中水平表达,滤泡亚型也归于此组;核特征高水平表达的病例,多为经典型PTC;实体型与弥漫硬化型的核特征表达水平偏低.(3)从核特征"量化"角度分析,当其呈中水平表达时,已满足非浸润性经典型PTC的诊断阈值.(4)中等水平表达的核特征,达到滤泡型PTC(理论上包括包裹性滤泡型PTC)的诊断条件,即WHO定义所描述的"特征性核需占肿瘤相当大的部分".%Purpose To explore the feasibilities of quantificational evaluations of the diagnostic nuclear features, including nuclear grooves, nuclear crowding, ground glass nuclei as well as nuclear pseudoinclusions in papillary thyroid carcinoma ( PTC ), and to estimate the quantitative thresholds for the diagnosis of PTC. Methods 80 cases of PTCs were semiquantitatively divided into higher, moderate and lower-level expression groups on the basis of distributional and grading status of diagnostic nuclear features. Results 88% ( 70/80 ) of PTCs presented with the four nuclear features, and 12%( 10/80 )showed three features. Nevertheless, no cases displayed just two or even less nuclear morphology. 20% ( 16/80 ) of PTCs were categorized in the higher expression group, 74% ( 59/ 80 ) were listed as moderate expression group, and 5% were ranked in the lower-level group. Statistically, the scattering pattern conformed to the positively-skewed distribution. As for the histologic variants, the higher expression group comprised of conventional and micorcarcinoma variants. The moderate-level group contained conventional, microcarcinoma, follicular, tall cell, oncocytic cell, clear cell, cribrifonn-morular and solid variants. The lower-level group covered conventional, solid and diffuse seclerosing variants. 10% ( 8/80 ) of PTCs were of non-invasion ( niPTC ) and all of which were identified as encapsulated classical PTC in morphology. niPTCs occupied 19% ( 3/16 ), 8% ( 5/59 ) and 0 ( 0/5 ) of PTCs in the higher, moderate and lower expression groups, respectively. Conclusions A definate diagnosis of PTCs possibly needs to reach the threshold that no less than three nuclear features are displayed simultaneously. Most of PTCs show moderate-level expression of the nuclear features and the follicular variants are also ranked in this group. Conventional PTCs constitute the major parts of the higher expression group. The solid and diffuse sclerosing variants generally manifest lower expression of the nuclear features. Moderate-level expression of nuclear features has reached the diagnostic thresholds for follicular variant of PTC ( theoretically including encapsulated follicular variant of PTC ) and non-invasively conventional PTC.