Diagnosis of small colorectal lesions in a non-academic setting.

Background:

Several endoscopic imaging techniques have recently been developed in order to improve differentiation of premalignant adenomas from innocent, non-neoplastic polyps. Accurate in-vivo optical diagnosis of polyps less than 10mm in size can be an acceptable strategy to assess polyp histopathology and future surveillance intervals. Furthermore, dispensing without formal histopathology for most small polyps could improve the efficiency of the procedure and lead to substantial savings in time and costs. This surveillance strategy based on optical diagnosis appears suitable for incorporation in future guidelines but has never been assessed in a non-expert setting.



Aims:

This study proposal aims to assess the accuracy of optical diagnosis with white light and narrow-band imaging (NBI) in colonic lesions smaller than 10 mm in a non-expert setting. Furthermore, the difference in accuracy of Kudo pit-pattern and VPI during NBI for differentiation will be assessed.



Methods:

Each detected lesion will be inspected with high definition white light endoscopy and NBI (Kudo pit pattern and VPI) for differentiation and the endoscopist will be asked to predict histopathology. Subsequently, the endoscopist will state on the basis of optical diagnosis alone whether he has high confidence in differentiating the lesion (e.g. whether he would leave it in situ or resect and discard the lesion) or whether he has low confidence in differentiating the lesion (e.g. resect and send the polyp for histopathology).
Regardless of the confidence of the endoscopist, all lesions included in the analysis will be biopsied or resected at the end of the optical diagnosis and send for histopathology.

The current study evaluates whether accurate optical diagnosis of small colorectal polyps (<10mm) in vivo in a non-expert setting can be achieved, resulting in the omission of formal histopathology, which could make colonoscopy more efficient and cost effective.

N/A

All participating endoscopists differentiate colorectal lesions with white-light and NBI and will indicate whether they have high confidence or low confidence in the differentiation. Subsequently, the endoscopists will decide on the management of the lesion; whether they will resect and discard it (high confidence, no formal histopathology), resect and send it for histopathology (low confidence, if they cannot decide on the type of polyp or are concerned about malignancy) or leave it in situ (high confidence). Furthermore, a recommendation for surveillance interval is recorded.

For study purposes, all lesions included in the analysis will be biopsied or resected at the end of the optical diagnosis and send for histopathology.