Endoscopic Ultrasound Elastography as a Novel Diagnostic Method for the Assessment of Hardness and Depth of Invasion in Colorectal Neoplasms

Abstract

<b><i>Introduction:</i></b> We aimed to compare the efficacy of endoscopic ultrasound elastography (EUS-EG) with that of magnifying chromoendoscopy (MCE) and endoscopic ultrasonography (EUS) for the diagnosis of the depth of invasion in colorectal neoplasms. This is an important clinical issue as the depth of invasion is associated with the risk of metastasis. <b><i>Methods:</i></b> Consecutive patients with suspected superficial colorectal neoplasms, evaluated by MCE, EUS, and EUS-EG, for whom endoscopic submucosal dissection was considered, were enrolled in 2018 (derivation study) and in 2019–2020 (validation study). The primary clinical endpoint was the diagnostic yield differentiating intramucosal and shallow submucosal neoplasms from deep submucosal (dSM) and advanced colorectal cancers. In addition, inter- and intra-observer agreements of the elastic score of colorectal neoplasm (ES-CRN) were evaluated by 2 expert and 2 non-expert endoscopists. <b><i>Results:</i></b> Thirty-one (33 lesions) and 50 (55 lesions) patients were enrolled in the derivation and validation studies, respectively. Sensitivity, specificity, positive, and negative predictive values, and accuracy of assessment of the depth of submucosal or deeper invasion in the derivation and validation groups were as follows: EUS-EG, 100/88.2/86.7/100/93.3% and 77.8/86.1/73.7/88.6/83.3%; MCE, 66.7/94.4/90.9/77.3/81.8% and 84.2/91.4/84.2/91.4/88.9%; and EUS, 93.3/77.8/77.8/93.3/84.8% and 89.5/65.7/58.6/92.0/74.1%, respectively. For the 2 expert endoscopists, interobserver agreement for the ES-CRN (first and second assessments) in the derivation group was 0.84 and 0.78, respectively; these values were 0.73 and 0.49, respectively, for the 2 non-expert endoscopists. <b><i>Discussion/Conclusion:</i></b> All 3 modalities presented similar diagnostic yield. Inter- and intra-observer agreements of the ES-CRN were substantial, even for non-expert endoscopists. Therefore, EUS-EG may be a useful modality in determining the depth of invasion in colorectal neoplasms.

Towards targeted colorectal cancer biopsy based on tissue morphology assessment by compression optical coherence elastography

“…This improves the quality of staging of colorectal adenomas and early cancers compared with the use of endoscopic ultrasound alone and may provide more accurate selection of patients suitable for local resection ( 69 ). One of the latest studies of endoscopic ultrasound elastography is related to the diagnosis of the depth of invasion of colorectal cancer ( 70 ), however, the resolution of ultrasound is insufficient to determine the morphological features of the structure of the tumor node at the level of individual morphological patterns, which is also not presented for any of the technologies discussed above.…”

Tissue Elasticity as a Diagnostic Marker of Molecular Mutations in Morphologically Heterogeneous Colorectal Cancer

“…Using structural OCT, it has been proven that attenuation coefficient mapping [51] and resorting to machine learning [52] allow for improving quantitative diagnostic results. Further, the application of ultrasound elastography has been successful in visualizing the depth of CRC invasion [53]. The combination of OCT and elastography in one technology-C-OCE-allowed getting closer to the CRC morphology and made it possible to distinguish the CRC morphological patterns of the tumor node [43].…”

Fundamentals of Bowel Cancer for Biomedical Engineers

“…Shear waves can propagate in a near-cylindrical conical space, allowing real-time monitoring of shear wave velocities and Young’s modulus, and generating quantitative elastic elastograms. 28 Chen et al . 19 stated that cancer’s stiffness is the best staging criterion among all features to assess the staging of rectal tumours.…”