Molecular profile and clinicopathologic features of follicular variant papillary thyroid carcinoma
Thyroid World Congress ePoster Library. Sohn S. 06/21/19; 272130; 46
Seo Young Sohn
Seo Young Sohn
Login now to access Regular content available to all registered users.

You may also access this content "anytime, anywhere" with the Free MULTILEARNING App for iOS and Android
Abstract
Rate & Comment (0)

Background: The non-invasive encapsulated follicular variant of papillary thyroid carcinoma (FVPTC) has an indolent clinical behavior. Recently, it was proposed that this tumor type should be reclassified as non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP). To characterize NIFTPs, we evaluated the molecular and clinicopathologic characteristics of each FVPTC subtype.

Methods: This study enrolled 29 patients with FVPTC who underwent thyroidectomy between January 2007 and June 2017. They were classified as non-invasive encapsulated FVPTC (NIFTP, n = 10), invasive encapsulated FVPTC (n = 11), and infiltrative FVPTC (n = 8) by two independent pathologists. Genetic alterations were analyzed by targeted next-generation sequencing using formalin-fixed, paraffin-embedded tissue samples and the clinicopathologic characteristics were retrospectively reviewed.

Results: There was no difference in preoperative cytologic classification between NIFTPs and invasive encapsulated FVPTCs, whereas infiltrative FVPTC was more likely to be Bethesda class VI than the encapsulated type (50% versus 9.5%; P = 0.033). Lymph node metastasis was not found in NIFTPs. There was no BRAFV600E mutation in NIFTPs, whereas one of 11 invasive encapsulated FVPTCs and three of 8 infiltrative FVPTCs harbored BRAFV600E. RAS mutations were frequently detected in encapsulated FVPTCs (5 of 10 NIFTPs and 4 of 11 invasive encapsulated FVPTCs) but were only detected in one case of the infiltrative type.

Conclusions: There were no differences in molecular or clinicopathologic profiles between non-invasive and invasive encapsulated FVPTCs, except for lymph node metastasis and the presence of BRAFV600E. NIFTP has favorable pathologic characteristics with a high frequency of RAS mutations.


Background: The non-invasive encapsulated follicular variant of papillary thyroid carcinoma (FVPTC) has an indolent clinical behavior. Recently, it was proposed that this tumor type should be reclassified as non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP). To characterize NIFTPs, we evaluated the molecular and clinicopathologic characteristics of each FVPTC subtype.

Methods: This study enrolled 29 patients with FVPTC who underwent thyroidectomy between January 2007 and June 2017. They were classified as non-invasive encapsulated FVPTC (NIFTP, n = 10), invasive encapsulated FVPTC (n = 11), and infiltrative FVPTC (n = 8) by two independent pathologists. Genetic alterations were analyzed by targeted next-generation sequencing using formalin-fixed, paraffin-embedded tissue samples and the clinicopathologic characteristics were retrospectively reviewed.

Results: There was no difference in preoperative cytologic classification between NIFTPs and invasive encapsulated FVPTCs, whereas infiltrative FVPTC was more likely to be Bethesda class VI than the encapsulated type (50% versus 9.5%; P = 0.033). Lymph node metastasis was not found in NIFTPs. There was no BRAFV600E mutation in NIFTPs, whereas one of 11 invasive encapsulated FVPTCs and three of 8 infiltrative FVPTCs harbored BRAFV600E. RAS mutations were frequently detected in encapsulated FVPTCs (5 of 10 NIFTPs and 4 of 11 invasive encapsulated FVPTCs) but were only detected in one case of the infiltrative type.

Conclusions: There were no differences in molecular or clinicopathologic profiles between non-invasive and invasive encapsulated FVPTCs, except for lymph node metastasis and the presence of BRAFV600E. NIFTP has favorable pathologic characteristics with a high frequency of RAS mutations.


    This eLearning portal is powered by:
    This eLearning portal is powered by MULTIEPORTAL
Anonymous User Privacy Preferences

Strictly Necessary Cookies (Always Active)

MULTILEARNING platforms and tools hereinafter referred as “MLG SOFTWARE” are provided to you as pure educational platforms/services requiring cookies to operate. In the case of the MLG SOFTWARE, cookies are essential for the Platform to function properly for the provision of education. If these cookies are disabled, a large subset of the functionality provided by the Platform will either be unavailable or cease to work as expected. The MLG SOFTWARE do not capture non-essential activities such as menu items and listings you click on or pages viewed.


Performance Cookies

Performance cookies are used to analyse how visitors use a website in order to provide a better user experience.


Save Settings