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

BACKGROUND/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.

Crypt-rings in tandem detected in infectious colitis, in IBD and in IBD-associated noninvasive neoplasia

AIMS

Recently, eight novel histologic structures in colon mucosa with inflammation were described. Here, we assessed the frequency of one of them: crypt rings in tandem (CRT), in patients with infectious colitis (IC), IBD (ulcerative colitis; UC or Crohn colitis; CrC) and UC in remission (UCR). In addition, the frequency of dysplastic CRT (DCRT) in IBD-associated noninvasive neoplasia (IBDNIN) were also calculated.

METHODS

Colon biopsies in 578 cases were reviewed: 42 cases with IC, 280 with IBD (180 UC and 100 CrC), 100 UCR and the remaining 156, IBDNIN.

RESULTS

The proportions of CRT in IC was 16.7%, in IBD 14.3% %, in UCR 3%, and of DCRT in IBDNIN, 20%. No differences were recorded between the proportions of CRT in IC, UC and CrC. Conversely, the difference in CRT frequency between UC and UCR, and between CRT and DCRT were significant (P = 0.006, and p = 0.05, respectively).

CONCLUSIONS

CRT evolved in IC and in IBD. The finding of CRT in IC strongly suggest that those characteristic crypts were shaped at the early stages of mucosal inflammation. CRT persisted in IBD with protracted inflammation but plummeted in UCR, that is when the mucosal inflammation waned. The proportion of DCRT was significantly higher than that of CRT. It is submitted that DCRT might had developed in IBDNIN using CRT as scaffolds. This is the first study in which a characteristic pathologic aberration of cryptogenesis was tracked in colon biopsies from patients with IBD and with IBD-associated neoplastic transformation.

Dysplastic Crypts in Asymmetric Branching in Ulcerative Colitis: A Preliminary Report

AIM

To report the detection of dysplastic crypts in asymmetric branching (DCAB) in biopsies from patients with ulcerative colitis (UC).

PATIENTS AND METHODS

One hundred consecutive endoscopic biopsies from patients with UC undergoing surveillance were reviewed.

RESULTS

Three biopsy/cases showed DCAB. The frequency of DCAB varied from two in one case, three in another case, and five in the remaining case.

CONCLUSION

The final outcome of DCAB is to generate two or more dysplastic asymmetric offspring-crypts. Repeated DCAB offspring formation, together with new DCAB, would boost the pool of dysplastic crypts, resulting in an exponential expansion of the mucosal area occupied by dysplasia in UC.

Crypts in Asymmetric Fission in Endoscopic Biopsies from German Patients With Inflammatory Bowel Disease

BACKGROUND/AIM

We previously found in Swedish patients with inflammatory bowel disease (IBD), crypts in symmetric fission (CSF) and in asymmetric fission (CAF). This study aimed to examine CSF and CAF in a cohort of German patients with IBD.

PATIENTS AND METHODS

H&E-sections from 106 IBD-patients [59 ulcerative colitis (UC) and 47 Crohn colitis (CCs)] were analysed.

RESULTS

A total of 588 crypts in fission (CF) were found; 342 (58.2%) in UC and 246 (41.8%) in CCs. Out of the 505 CAFs found, 304 (60.2%) were recorded in UC, and 201(39.8%) in CCs (p=0.15272).

CONCLUSION

Despite that German and Swedish populations reside in disparate geographical regions with different ecological milieus, the proportions of CAF and CSF were similar, thereby suggesting that CAF and CSF develop in IBD independently of the local environmental conditions in the two regions.

Crypts in Asymmetric Fission in Endoscopic Biopsies from Swedish Patients With Inflammatory Bowel Disease

BACKGROUND/AIM

We previously found crypts in symmetric fission (CSF) and in asymmetric fission (CAF) in colectomy-specimens with ulcerative colitis. We now analyzed CSF and CAF (CSAF) in biopsies from 80 patients with inflammatory bowel disease (IBD) without dysplasia or carcinoma.

PATIENTS AND METHODS

One unselected double-biopsy from affected endoscopic areas was investigated in the 80 cases.

RESULTS

A total of 353 crypts in fission were found. The median number of CAF/biopsy was 3.7 and for CSF/biopsy, 0.7 (p<0.00001).

CONCLUSION

CSAF often occur in unselected biopsies from patients with IBD. Whereas the increased frequency of CSF might mirror a compensatory mechanism of crypt production in areas occupied by inflammation, CAF reflects a pathological aberration of cryptogenesis, probably generated by somatic mutations. The biological significance of CAF in IBD without dysplasia or carcinoma, deserves to be further investigated.

Micro ATR-FTIR spectroscopic imaging of colon biopsies with a large area Ge crystal

A new large-area germanium ATR crystal is utilised with an FTIR microscope to improve the acquired images of de-paraffinized colon biopsy sections, without recourse to a synchrotron source. The large crystal (⌀ = 28 mm) offers significant improvements compared to slide-on small germanium crystal (⌀ = 3.5 mm); for example, it facilitates more uniform distribution of higher signal intensity within the field of view and more rapid acquisition time. Mapping of a larger sample area up to ca. 350 × 350 μm² with this new set-up, coupled with imaging using an FPA detector, is demonstrated for the first time on biological specimens. The performance of k-means clustering algorithm applied to classify the different anatomical structures of the colon biopsies is greatly improved with mapping. Comparison of H&E stained adjacent tissue sections with false-colour k-means images strongly support differentiation of five distinct regions within tissues. The efficiency of the methodology to categorise colon tissues at various stages of malignancy is analysed via multivariate chemometrics. The second derivative spectra extracted from the crypt region of the colon were subjected to Partial Least Squares classification. Good separation between data in clusters occurs when projecting spectra on a PLS score plot on a plane made by the first 3 principal components. Important spectral biomarkers for colon malignancy classification were identified to exist mostly in the fingerprint region of the FTIR spectrum based on the chemometrics analysis.

Surveillance for colitis-associated colon neoplasia

The risk of developing colon cancer is increased in colitis patients, particularly if the disease is extensive and its duration long-standing. Endoscopic guidelines have been developed with the goal of detecting early neoplastic changes prior to development of advanced malignancy. Unfortunately, the natural history of this superimposed neoplastic process in colitis appears to be very heterogeneous and poorly understood. Moreover, there are numerous confounding variables in colitis patients that limit accurate assessment of the surveillance effectiveness of colonoscopy and multi-site biopsy protocols. Although the clinical challenge posed to even the most experienced clinicians remains significant, evolving methods of endoscopic imaging may facilitate better evaluation of this highly select group of patients.