Papotti M, Volante M, Giuliano A, Fassina A, Fusco A, Bussolati G, Santoro M, Chiappetta G
Dipartimenti di Anatomia Patologica, Università di Torino, Italy.
Am J Surg Pathol. 2000 Dec;24(12):1615-21. doi: 10.1097/00000478-200012000-00004.
Hyalinizing trabecular tumor (HTT) of the thyroid is a neoplasm of follicular derivation with a histogenesis that is still the subject of debate. Morphologic affinities between HTT and papillary carcinoma, including nuclear pseudoinclusions and grooves, suggest that these tumors may be of similar origin. The authors investigated the relationship between these two types of tumors by assessing HTT for the presence of rearrangements of the proto-oncogene rearranged during transfection (RET) that, in thyroid tumors, are specific for papillary carcinoma. A series of 14 HTTs, including two cases associated with classic papillary carcinoma, was studied by means of immunohistochemistry and reverse transcription-polymerase chain reaction. Seven follicular adenomas with focal hyalinized trabecular areas served as control cases. Three of the 14 HTT cases under consideration displayed rearrangements of RET generating the RET/papillary thyroid carcinoma type 1 (PTC1) oncogene. In another case, RET expression was detected focally by immunohistochemistry alone. Finally, in one mixed HTT-papillary carcinoma sample, RET/PTC1 expression was detected, but only in the papillary component. None of the control follicular adenomas contained rearrangements of RET/PTC. These findings demonstrate that a comparable percentage (28.6%) of HTTs and papillary carcinomas exhibit the same RET proto-oncogene alterations. Thus, HTT may represent the "hyalinizing trabecular" variant of papillary carcinoma rather than a separate entity.
甲状腺透明变梁状肿瘤（HTT）是一种滤泡来源的肿瘤，其组织发生仍存在争议。HTT与乳头状癌之间的形态学相似性，包括核假包涵体和核沟，提示这些肿瘤可能起源相似。作者通过评估HTT中原癌基因转染重排（RET）的重排情况来研究这两种肿瘤之间的关系，在甲状腺肿瘤中，RET重排是乳头状癌所特有的。通过免疫组织化学和逆转录-聚合酶链反应对14例HTT进行了研究，其中包括2例与经典乳头状癌相关的病例。7例有局灶性透明变梁状区域的滤泡性腺瘤作为对照病例。在14例被研究的HTT病例中，有3例显示RET重排，产生了RET/甲状腺乳头状癌1型（PTC1）癌基因。在另一例病例中，仅通过免疫组织化学在局部检测到RET表达。最后，在一个HTT与乳头状癌的混合样本中，检测到了RET/PTC1表达，但仅在乳头状成分中。对照滤泡性腺瘤均未检测到RET/PTC重排。这些发现表明，相当比例（28.6%）的HTT和乳头状癌表现出相同的RET原癌基因改变。因此，HTT可能代表乳头状癌的“透明变梁状”变异型，而非一个独立的实体。
