These authors contributed equally to the completion of this manuscript.
Follicular variant of papillary thyroid carcinoma: Genome-wide appraisal of a controversial entity
Article first published online: 11 MAY 2004
Copyright © 2004 Wiley-Liss, Inc.
Genes, Chromosomes and Cancer
Volume 40, Issue 4, pages 355–364, August 2004
How to Cite
Wreesmann, V. B., Ghossein, R. A., Hezel, M., Banerjee, D., Shaha, A. R., Tuttle, R. M., Shah, J. P., Rao, P. H. and Singh, B. (2004), Follicular variant of papillary thyroid carcinoma: Genome-wide appraisal of a controversial entity. Genes Chromosom. Cancer, 40: 355–364. doi: 10.1002/gcc.20049
- Issue published online: 3 JUN 2004
- Article first published online: 11 MAY 2004
- Manuscript Accepted: 31 MAR 2004
- Manuscript Received: 21 NOV 2003
- American College of Surgeons
The majority of thyroid tumors are classified as papillary (papillary thyroid carcinomas; PTCs) or follicular neoplasms (follicular thyroid adenomas and carcinomas; FTA/FTC) based on nuclear features and the cellular growth pattern. However, classification of the follicular variant of papillary thyroid carcinoma (FVPTC) remains an issue of debate. These tumors contain a predominantly follicular growth pattern but display nuclear features and overall clinical behavior consistent with PTC. In this study, we used comparative genomic hybridization (CGH) to compare the global chromosomal aberrations in FVPTC to the PTC of classical variant (classical PTC) and FTA/FTC. In addition, we assessed the presence of peroxisome proliferator-activated receptor-gamma (PPARG) alteration, a genetic event specific to FTA/FTC, using Southern blot and immunohistochemistry analyses. In sharp contrast to the findings in classical PTC (4% of cases), CGH analysis demonstrated that both FVPTC (59% of cases) and FTA/FTC (36% of cases) were commonly characterized by aneuploidy (P = 0.0002). Moreover, the pattern of chromosomal aberrations (gains at chromosome arms 2q, 4q, 5q, 6q, 8q, and 13q and deletions at 1p, 9q, 16q, 17q, 19q, and 22q) in the follicular variant of PTC closely resembled that of FTA/FTC. Aberrations in PPARG were uniquely detected in FVPTC and FTA/FTC. Our findings suggest a stronger relationship between the FVPTC and FTA/FTC than previously appreciated and support further consideration of the current classification of thyroid neoplasms. © 2004 Wiley-Liss, Inc.