Advantagesanddisadvantages of different biopsy techniques
(Table 1.16)
The main advantage of endoscopic biopsies is the collection of biopsy samples under visualization.4 Therefore, samples are representative of mucosal lesions observed during endoscopy of the stomach, duodenum, terminal ileum, or colon.
The relatively small size (3-mm maximum diameter) of the samples is compensated for by the availability of multiple samples. The major disadvantages of endoscopic biopsies are crushing artefacts or the potential for insufficient depth, which can lead to separation within the mucosa. This is especially true for the duodenum, where the main problem is the distortion and disruption of villi, in particular when samples are collected blindly. Another disadvantage is the limited access to the jejunum and ileum. Furthermore, endoscopic biopsies are not deep enough to allow for evaluation of submucosal structures. Finally, the mucosa cannot be oriented prior to sectioning. However, in our own experience orientation within a good quality endoscopic biopsy is sufficient to identify structural alterations typical for many if not most intestinal diseases. The ideal endoscopic biopsy sample to enable histopathological diagnosis should include intact mucosa, with attached muscu- laris mucosae and parts of the submucosa, even if the relationship and size of villi and crypts cannot be determined accurately in comparison to full-thickness biopsies.Advantages of full-thickness biopsies include the larger size compared to endoscopic biopsies leading to easier handling and orientation. Also, when abnormalities are located outside the mucosa, such as a leiomyoma or plexus lesions, or if endoscopic biopsies are inconclusive due to size, poor quality, or a non-representative sample, full-thickness biopsies can lead to a diagnosis. Also, crushing and disruption artefacts are rare with full-thickness biopsies. The disadvantages of full-thickness biopsies include the limited number of specimens that can be collected and the degree of invasiveness, which can be associated with an increased risk for complications.
The main advantage of fine-needle aspiration, brushing, or curettage is the ease and inexpensiveness of these procedures (see 1.7). However, they cannot reflect structural changes.
1.8.4