Patologìâ (Aug 2024)
Diagnostic accuracy of endoscopic optical evaluation and forceps biopsy in comparison with pathohistological findings of colorectal laterally spreading tumors
Abstract
Following the principles of image-enhanced endoscopy and using standardized endoscopic classifications, it is possible to predict the morphological diagnosis of colorectal neoplasms with high accuracy. The large size and uneven surface of lesion significantly complicates a thorough examination, and routine biopsy is still widely practiced, despite its drawbacks. This makes it necessary to compare the results of optical and forceps biopsy and determine the expediency of performing the latter for different types of colorectal laterally spreading tumors (LST). Aim. To compare the pit and vascular pattern, determined endoscopically, with histopathological findings in LST, with the calculation of the diagnostic accuracy of optical evaluation and forceps biopsy. To ascertain the relationship between lesion size, morphological type, and the presence of malignant changes. Materials and methods. 80 LST ≥20 mm were included in the study. Expert image-enhanced endoscopy with NBI and utilizing Paris, Kudo, JNET and Hiroshima classifications was employed for optical evaluation and stratification of lesions. Target forceps biopsy was obtained from areas showing the most progressive changes. The data from optical biopsy and the pathohistology of forceps biopsy specimens were compared with the results of the pathohistological findings of removed LST. Statistics were calculated in the Statistica 13. Results. Group 1 comprised 30 patients with non-granular type LST, while group 2 consisted of 50 patients with granular type LST. The median diameter was 20 mm (IQR, 20; 25) and 40 mm (IQR, 25; 50), adenocarcinoma loci were found in 10 % and 32 % in the first and second groups, respectively. Correlations between lesion localization and LST subtype were assessed, as well as between the presence of malignant changes and the size and morphological type of the lesions. Comparative indicators of sensitivity (80.0 % / 81.8 % in the first and 76.7 % / 80.0 % in the second group), diagnostic accuracy (93.3 % for both methods in the first and 84.0 % / 86.0 % in the second group), and also predictive values were revealed for optical evaluation / forceps biopsy, respectively. The specificity was identical and amounted to 100 % in the first and 95 % in the second group. In all cases, p < 0.01. Conclusions. Mixed type LST-G lesions occur more often in the rectum, whereas flat elevated LST-NG lesions – in the transverse colon. The presence of adenocarcinoma correlates with the morphological type of tubulovillous adenoma and the larger size of the tumor; larger LSTs are more frequently tubulovillous adenomas. Optical and forceps biopsies demonstrate higher accuracy for non-granular types of LST compared to granular types. Forceps biopsy does not confer any advantages over optical biopsy and is not recommended for routine use.
Keywords
