McLeod M K
Division of Endocrine Surgery, University of Michigan Medical Center, Ann Arbor.
Otolaryngol Clin North Am. 1990 Apr;23(2):271-90.
It is clear that the DNA content of endocrine cells is influenced by factors other than neoplastic change and transformation. Although it can be concluded that, in general, the DNA content of neoplasms is increased, it is less clear whether this increase in DNA content is the cause or the effect of neoplastic transformation. The actual consequences of an increased DNA content are still largely unknown. However, based on a substantial body of data on the measure of nuclear DNA content in thyroid neoplasms, several conclusions appear to be reasonable. First, the measurement of nuclear DNA content and ploidy analysis are not sufficiently reliable parameters upon which to distinguish a benign from a malignant thyroid neoplasm. Therefore, this parameter has failed to live up to the expectation that it would be a powerful diagnostic tool. Second, the measurement of nuclear DNA content is useful after a histomorphologic diagnosis has been made since it correlates very well with the prognosis and clinical outcome of the patient. It is clear that aneuploid thyroid carcinomas are responsible for earlier recurrence, an increased likelihood of distant and diffuse metastases, and an increased incidence of death compared with diploid thyroid carcinomas. Except for the rare occasion, diploidy implies a uniformly long-term survival whereas aneuploidy is associated with a variable clinical course. Irrespective of histomorphology, lethal lesions of the thyroid are invariably aneuploid, whereas lesions associated with prolonged survival or a favorable outcome can be either diploid or aneuploid. Aneuploidy in well-differentiated thyroid carcinoma is more likely in older patients, in less well-differentiated neoplasms, and in neoplasms infiltrating beyond the thyroid capsule. Age, type of neoplasm, extrathyroidal extension, and recurrent disease all appear to be more important prognostic variables than is nuclear DNA content. However, nuclear DNA content can increase the prognostic power of these variables and consequently may come to be increasingly useful in the management of some patients with thyroid neoplasms. After a histomorphologic diagnosis has been made, the measurement of nuclear DNA content and a determination of the DNA ploidy may have significant prognostic value.
显然，内分泌细胞的DNA含量受肿瘤性改变和转化以外的因素影响。虽然可以得出结论，一般来说肿瘤的DNA含量会增加，但DNA含量的这种增加是肿瘤转化的原因还是结果，尚不太明确。DNA含量增加的实际后果在很大程度上仍然未知。然而，基于大量关于甲状腺肿瘤核DNA含量测量的数据，一些结论似乎是合理的。首先，核DNA含量的测量和倍性分析并不是区分甲状腺良性肿瘤和恶性肿瘤的足够可靠的参数。因此，这个参数未能达到成为强大诊断工具的期望。其次，在做出组织形态学诊断后，核DNA含量的测量是有用的，因为它与患者的预后和临床结果密切相关。显然，与二倍体甲状腺癌相比，非整倍体甲状腺癌更容易早期复发、远处和弥漫性转移的可能性增加以及死亡发生率增加。除了极少数情况外，二倍体意味着一致的长期生存，而非整倍体与可变的临床病程相关。无论组织形态如何，甲状腺的致命性病变总是非整倍体，而与长期生存或良好结果相关的病变可以是二倍体或非整倍体。在老年患者、分化较差的肿瘤以及浸润超出甲状腺包膜的肿瘤中，分化良好的甲状腺癌中非整倍体的可能性更大。年龄、肿瘤类型、甲状腺外扩展和复发性疾病似乎都是比核DNA含量更重要的预后变量。然而，核DNA含量可以增加这些变量的预后能力，因此在一些甲状腺肿瘤患者的管理中可能会越来越有用。在做出组织形态学诊断后，核DNA含量的测量和DNA倍性的测定可能具有重要的预后价值。
