Diagnostic accuracy of features predicting lower gastrointestinal malignancy: a colonoscopy database review of 10 603 Chinese patients

Aim The diagnostic accuracy of colonoscopic features in predicting colorectal cancer (CRC) malignancy was studied. Method Consecutive patients who underwent first-time colonoscopy for lower gastrointestinal (GI) symptoms from 1998 to 2009 were identified. Gender, age, symptoms, endoscopic and pathologic findings were reviewed. Results There were 10 603 patients. The overall prevalence of malignancy was 3.0% (313). Among these, only 58% (181/313) had features indicative of tumour formation. The overall sensitivity and specificity was 9.6% and 94.1%, respectively. The overall positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio were 2.66, 0.96 and 2.77, respectively. Conclusion A large proportion of Chinese patients with CRC presented without features indicative of tumour formation.