Objective:Signet ring cell carcinoma is a rare subtype of colorectal carcinoma(CRC)with an associated BRAFV600E mutation.We investigated frequencies of BRAF mutation in 28 CRCs containing variable signet ring cell com...Objective:Signet ring cell carcinoma is a rare subtype of colorectal carcinoma(CRC)with an associated BRAFV600E mutation.We investigated frequencies of BRAF mutation in 28 CRCs containing variable signet ring cell component and their relation with clinicopathologic parameters.Methods:According to the presence of signet ring cell component,tumors were categorized into groups as follows:0%–9%,10%–24%,25%–49%,and>50%.Genomic DNA was isolated and analyzed for BRAF V600E gene mutation by polymerase chain reaction-restriction fragment length polymorphism.Eleven of 28 cases(39.3%)showed BRAFV600E mutation,which was also confirmed by Sanger sequencing.To elucidate the importance of existence of signet ring cell component at the molecular level,we separated cases into two groups with cut-off levels of 10%and 50%,which pertain to percentages of signet ring cells.Results:Seven of 19 cases(36.8%)under the threshold of 50%and four of nine cases(44.4%)over this threshold value demonstrated BRAF mutation.Three of 7 cases(42.8%)featuring<10%signet ring cell component and eight out of 21 cases(38.1%)showing>10%were BRAF mutated.Conclusions:BRAF mutation must be closely associated with the presence of malignant signet ring cells regardless of their percentages.展开更多
文摘Objective:Signet ring cell carcinoma is a rare subtype of colorectal carcinoma(CRC)with an associated BRAFV600E mutation.We investigated frequencies of BRAF mutation in 28 CRCs containing variable signet ring cell component and their relation with clinicopathologic parameters.Methods:According to the presence of signet ring cell component,tumors were categorized into groups as follows:0%–9%,10%–24%,25%–49%,and>50%.Genomic DNA was isolated and analyzed for BRAF V600E gene mutation by polymerase chain reaction-restriction fragment length polymorphism.Eleven of 28 cases(39.3%)showed BRAFV600E mutation,which was also confirmed by Sanger sequencing.To elucidate the importance of existence of signet ring cell component at the molecular level,we separated cases into two groups with cut-off levels of 10%and 50%,which pertain to percentages of signet ring cells.Results:Seven of 19 cases(36.8%)under the threshold of 50%and four of nine cases(44.4%)over this threshold value demonstrated BRAF mutation.Three of 7 cases(42.8%)featuring<10%signet ring cell component and eight out of 21 cases(38.1%)showing>10%were BRAF mutated.Conclusions:BRAF mutation must be closely associated with the presence of malignant signet ring cells regardless of their percentages.
