Is the Routine Histopathologic Diagnosis of Ulcerative Colitis Based on Cross-cut Sections or on Well-oriented Sections?

Abstract

ackground/Aim: For many years, it was empirically estimated that the majority of the routine colon biopsies in Swedish patients with ulcerative colitis (UC), exhibited cross-cut crypts. The aim of the present study was to assess the frequency of cross-cut crypts (CCC) and well-oriented crypts in routine colon biopsies in German patients with UC. Patients and Methods: In total, 447 colon biopsies: 376 with UC and 71 controls were investigated. Results: Out of 376 colon biopsies with UC, 73% exhibited ≥60% CCC. Out of the 237 biopsies showing ≥80% CCC, as many as 71% exhibited 100% CCC in individual biopsies. Similar percentages were found in control biopsies. Conclusion: The majority of the routine colon biopsies with UC, as well as control biopsies in German patients displayed CCC. Thus, an unnoticed, consequent, and systematic cutting technical hitch was introduced during the laboratory processing of colon biopsies. The reason(s) behind the similar histologic processing mode of colon biopsies at the two geographically disparate laboratories (Sweden and Germany) remains elusive. The cross-cutting mode influenced the narrative of biopsies in UC, inasmuch as some histological parameters listed among well-oriented colon sections were not present in sections displaying CCC.

The Histology-Driven Differential Diagnosis in Bowel Inflammatory Conditions Is Not All That Obvious: Evidence from a Survey Based on Digital Slides

“…A series of studies, mainly conducted by Rubio and coworkers, has underlined the importance of crypt asymmetrical branching of regenerating crypts after chronic neutrophil-driven damage as an instrument for a more precise definition of crypt distortion [17,18]. Recently, the same group demonstrated that specimen orientation could represent a bias in crypt morphology evaluation; a significant portion of the histologic section that resulted in a diagnosis of IBD held cross-cut crypts, an inappropriate sectioning plane that modifies the correct assessment of the other histological parameters that defined the diagnosis of IBD [19][20][21]. On the other side, a series of cryptassociated anomalies were described in addition to crypt branching in crypt destructive inflammations that should be considered in their assessment on histologic slides [22].…”