The T1799A BRAF mutation is absent in cribriform-morular variant of papillary carcinoma.
BACKGROUND
Cribriform-morular variant of papillary thyroid carcinoma (CMVPTC) is one of the rare types of papillary carcinoma. It has been associated with familial adenomatous polyposis, though it can also occur sporadically. The molecular pathogenesis of this tumor is incompletely understood. It appears that there can be molecular contributions from the RET/PTC translocations and from mutations in the APC gene and beta-catenin gene, which are both part of the Wnt signaling pathway. However, one of the most common mutations in papillary carcinoma, the BRAF mutation, has not been reported in this variant of papillary carcinoma.


OBJECTIVE
To investigate the BRAF mutational status in CMVPTC.


METHODS
Four cases of CMVPTC (1 associated with familial adenomatous polyposis and the others apparently sporadic) were identified from the files of 3 large centers. Deoxyribonucleic acid was extracted and successfully amplified from each case. The polymerase chain reaction products were sequenced and evaluated for the T1799A BRAF mutation.


RESULTS
None of the 4 cases harbored the T1799A BRAF mutation (0/4). Conclusions.-The T1799A BRAF mutation does not appear to play a role in the tumorigenesis of CMVPTC.
Department of Anatomic Pathology, Cleveland Clinic, Ohio 44195, USA.
David
D
Schuetze
Aaron P
AP
Hoschar
Raja R
RR
Seethala
Adel
A
Assaad
Xiatong
X
Zhang
Jennifer L
JL
Hunt
D000231:Adenocarcinoma, Papillary / Q000235:genetics* / Q000473:pathology; D011125:Adenomatous Polyposis Coli / Q000235:genetics / Q000473:pathology; D004252:DNA Mutational Analysis; D004273:DNA, Neoplasm / Q000032:analysis; D006801:Humans; D017354:Point Mutation; D048493:Proto-Oncogene Proteins B-raf / Q000235:genetics*; D013964:Thyroid Neoplasms / Q000235:genetics* / Q000473:pathology
D004273:DNA, Neoplasm; C482119:BRAF protein, human; D048493:Proto-Oncogene Proteins B-raf