Confocal laser endomicroscopy for the diagnosis of colorectal cancer in vivo


  • Conflict of interest: None.

Correspondence to: Yan Qing LI, Department of Gastroenterology, Laboratory of Translational Gastroenterology, Qilu Hospital of Shandong University, 107 Wenhuaxi Road, Jinan, Shandong Province 250012, China. Email:



To evaluate the feasibility and accuracy of confocal laser endomicroscopy (CLE) for the in vivo diagnosis of colorectal cancer (CRC) compared with conventional histology.


Consecutive patients who had undergone CLE examination for screening or surveillance colonoscopy were recruited. Suspected malignant lesions and adjacent mucosal sites were first examined by confocal imaging and then biopsied specimens of these sites were obtained. The confocal images were independently interpreted by two endoscopists. The diagnosis made with CLE was compared with the conventional histological diagnosis in a prospective and blinded fashion.


In total, 71 patients with suspected malignant lesions were included in the study. A total of 74 lesions and 92 adjacent mucosal sites were observed. The sensitivity, specificity and accuracy of CLE in diagnosing CRC were 97.1%, 99.0% and 98.2% for endoscopist A, and 98.6%, 96.9% and 97.6% for endoscopist B, respectively. The interobserver agreement between the two endoscopists was excellent (κ = 0.950). The accuracy of diagnosing poorly differentiated CRC using CLE was 97.0% for endoscopist A and 95.6% for endoscopist B.


CLE has the potential to enable an immediate diagnosis of CRC and the degree of differentiation of CRC during ongoing endoscopy in vivo.