Effects of rearranged during transfection mutation on calcitonin and procalcitonin expression in sporadic medullary thyroid carcinoma

Objective The aim of this study was to investigate the effects of rearranged during transfection(RET)mutation on the expressions of calcitonin(CTn)and procalcitonin(PCT)in sporadic medullary thyroid carcinoma(SMTC).Methods RET mutation was detected by polymerase chain reaction direct sequencing in 64 cases of SMTC,and the expression levels of CTn and PCT in SMTC tissues were detected using the immunohistochemical streptavidin-perosidase(SP)method.The effect of RET mutations on the expression of CTn and PCT along with its relationship with clinicopathological parameters were analyzed.Results The expression rates of CTn and PCT in SMTC tissues were 90.6%(58/64)and 67.2%(43/64),respectively.CTn and PCT expression were found to be associated with tumor size and lymph node metastasis(P<0.05)but not with gender,age,or tumor capsule invasion(P>0.05).There was a significant correlation between CTn and PCT expression(r=0.269,P=0.041),and the intensity of positive CTn expression was positively correlated with RET mutation(r=0.507,P=0.000).However,PCT expression was not associated with RET mutation(r=0.188,P=0.136).Conclusion High expression of CTn and PCT was associated with the progression of medullary carcinoma,and the intensity of CTn expression was associated with RET mutation.PCT may provide valuable information for the diagnosis and prognosis of SMTC.