Anaplastic Thyroid Cancer Evolved From Papillary Carcinoma: Demonstration of Anaplastic Transformation by Means of the Inter–Simple Sequence Repeat Polymerase Chain Reaction

• Published in: Archives of otolaryngology--head & neck surgery Vol. 129; no. 1; pp. 96 - 100
• Main Authors: Wiseman, Sam M, Loree, Thom R, Hicks, Wesley L, Rigual, Nestor R, Winston, Janet S, Tan, Donfeng, Anderson, Garth R, Stoler, Daniel L
• Format: Journal Article
• Language: English
• Published: Chicago, IL American Medical Association 01.01.2003
• Subjects: Aged; Biological and medical sciences; Brain Neoplasms - secondary; Carcinoma - pathology; Carcinoma, Squamous Cell - pathology; Carcinoma, Squamous Cell - secondary; Carcinoma, Squamous Cell - surgery; Cell Transformation, Neoplastic - pathology; Dissection - methods; Endocrinopathies; Fatal Outcome; Female; Humans; Malignant tumors; Medical sciences; Polymerase Chain Reaction - methods; Thyroid Neoplasms - pathology; Thyroid Neoplasms - surgery; Thyroid. Thyroid axis (diseases); Endocrinopathy; Human; Papillary carcinoma; Prognosis; Radiodiagnosis; Thyroid diseases; Thyroid gland; Malignant tumor; Carcinogenesis; Case study; Polymerase chain reaction; Anaplastic carcinoma; Malignant transformation; Medical imagery; Evolution; Female; Computerized axial tomography; Molecular biology; Elderly
• ISSN: 0886-4470; 1538-361X
• DOI: 10.1001/archotol.129.1.96

BACKGROUND In thyroid tumors, the coexistence of well- and poorly differentiated tumor types has led to the hypothesis that poorly differentiated thyroid tumors develop from well-differentiated thyroid tumors. By evaluating the genomic instability of histologically distinct but coexisting tumor foci, this study aimed to develop an improved understanding of thyroid tumorigenesis and tumor evolution. DESIGN Laser capture microdissection (LCM) was carried out on archival formalin-fixed, paraffin-embedded sections from a tumor containing foci of classic papillary thyroid cancer and anaplastic thyroid cancer. DNA was extracted from each microdissected tumor focus. In addition, cryopreserved bulk normal and neoplastic thyroid tissue underwent DNA extraction. All DNA samples were subsequently evaluated for genomic instability by means of inter–simple sequence repeat polymerase chain reaction. RESULTS The LCM DNA from each archival paraffin-embedded tumor focus demonstrated unique patterns of banding as compared with the cryopreserved tumor and normal tissue DNA. Thus, intratumoral variability in genomic instability was observed. Comparison of inter–simple sequence repeat polymerase chain reaction patterns of LCM DNA from adjacent foci of papillary and anaplastic tumors showed conserved genome alterations. CONCLUSIONS At the genome level, thyroid tumors may be highly heterogeneous. The intratumoral histologic heterogeneity observed in thyroid neoplasms reflects genetically heterogeneous underlying tumor cell populations that are demonstrated by the observed differences in their rates and extents of genomic instability. The conserved genomic alterations in the microdissected papillary and anaplastic foci suggest intratumoral evolution, with transformation of a preexisting papillary tumor to anaplastic carcinoma.Arch Otolaryngol Head Neck Surg. 2003;129:96-100-->