Diagnostic value of red cell distribution width in patients with benign or malignant lesions of bile duct

Objective To investigate the diagnostic value of red blood cell distribution to differenti- ate benign biliary stricture （BBS） from malignant biliary stricture （MBS）. Methods RDW and clinical features of biliary stricture lesions in 153 MBS patients were reviewed and compared with those 53 BBS pa- tients. Correlation analyses among RDW, CA19-9 and CEA were also performed. Results RDW in MBS group was significantly higher than that of BBS group （ P 〈 0.05 ）. The positive rates of RDW in MBS and BBS were 54. 1% and 18. 9% respectively, based on the prerequisite that RDW 〉 15% being the diagnostic value （P 〈 0.05）. The sensitivity and specificity of RDW in MBS diagnosis were 47% and 81% respective- ly. For patients with lower stricture （ I and II ）, RDW of MBS was significantly higher than that of BBS （P 〈 0. 001 ） ; while for patients with higher stricture （ 11I and 1V ）, the difference between MBS and BBS was not significant （P = 0. 505）. For both MBS and BBS, there was no significant difference in RDW be- tween strictures of Bismuth typeⅠ,Ⅱ and those of Ⅲ and Ⅳ （ both P 〉 0. 05）. In terms of correlation analy- sis, the RDW values were not positively correlated with CA19-9 （ r = 0. 099, P = 0. 201 ） or CEA （ r = O. 115, P=0. 152）. The diagnostic accuracy of CEA, CA199 and RDW for MBS were 69% , 79% and 64% respectively. Conclusion RDW is a valuable biochemical factor for discriminating MBS and BBS, which is independent of CA199 and CEA. Key words: Carcinoembryonic antigen;  Biliary tract diseases;  Diagnosis;  Red blood cell dis-tribution width