Original contributionIs atypical follicular adenoma of the thyroid a preinvasive malignancy?☆
Section snippets
Specimen selection and microscopic examination
Review of the pathology archives of Mackay Memorial Hospital showed 2 cases coded as atypical adenoma during the period 1997-2001. For comparison, 6 cases of follicular adenoma and 6 cases of follicular carcinoma diagnosed in the same period were selected using the hospital computer. The diagnostic criteria for these disease entities were based on previously described definitions.4
Hematoxylin and eosin-stained sections and paraffin-embedded blocks were available in all 14 cases. Histological
Results
On pathologic examination, the first atypical adenoma was characterized by hypercellularity with complete encapsulation. The tumor cells grew in trabecular to solid fashion. Most tumor cells were polygonal with moderately abundant cytoplasm and well-defined borders. The nuclei were normochromatic and round to oval. However, there was focal atypia characterized by nuclear hyperchromasia and pleomorphism (Fig 1A). Mitoses were not identified. The second case was characterized by trabecular,
Discussion
During the past decade, advances in molecular biology have enhanced understanding of the mechanisms of development in thyroid follicular cell neoplasms. For example, evidence indicates that the PTEN gene plays a role in the development of follicular adenoma, that a ras mutation is frequently found in follicular carcinomas, and that RET/TRK genetic rearrangements are found exclusively in papillary carcinomas.5 Mutation of the p53 gene is observed predominantly in anaplastic carcinoma3, 6, 7, 8
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Cited by (35)
Encapsulated thyroid tumors of follicular cell origin with high grade features (high mitotic rate/tumor necrosis): a clinicopathologic and molecular study
2010, Human PathologyCitation Excerpt :Their morphological criteria for poorly differentiated carcinoma are therefore very close to ours. Finally, Tzen et al [25] found P53 mutations in the pleomorphic cells of 2 atypical follicular adenomas. However, their cases did not have significant mitotic activity and tumor necrosis.
Prediction of KIT Mutation in Gastrointestinal Stromal Tumors by the Immunoprofile of the Tumor Cells
2010, Journal of the Formosan Medical AssociationFollicular Carcinoma
2009, Clinical Management of Thyroid DiseaseSpectrum and prognostication of KIT and PDGFRA mutation in gastrointestinal stromal tumors
2008, European Journal of Surgical OncologyCitation Excerpt :This study was approved by the Institutional Review Board of Mackay Memorial Hospital. DNA was isolated from formalin-fixed paraffin-embedded tumors according to previously described procedures.15 In brief, representative paraffin blocks of formalin-fixed tumor were cut at 8-μm using a clean disposable microtome blade for each block.
Thyroid adenomatous nodule with bizarre nuclei: A case report and mutation analysis of the p53 gene
2008, Pathology Research and Practice
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Supported in part by a grant from the National Science Council (NSC 89-2320-B-195-006).