Gastrointestinal dysplasia. Pathology. 2013;45:273-285. [PMID: 23442738 DOI: 10.1097/pat.0b013e32835f21d7]

Non-conventional dysplasias of the tubular gut: a review and illustration of their histomorphological spectrum

The increasing use of gastrointestinal endoscopic procedures has led to the recognition by histopathologists of non-conventional (or special-type) dysplasias of the gastrointestinal tract. These lesions can be recognised in association with prevalent underlying gastrointestinal conditions, such as Barrett oesophagus, chronic atrophic gastritis, and inflammatory bowel disease. The diagnosis of these special types can be challenging, and their biological behaviours are not fully characterised. The aim of this review is to provide a global view of non-conventional dysplastic lesions observed in the various segments of the tubular gastrointestinal tract and describe their salient features. Furthermore, as the clinical implications of these various subtypes have not been broadly tested in practice and are not represented in most management guidelines, we offer guidance on the best management practices for these lesions.

Effect of Helicobacter pylori infection and its eradication on gastric regenerating atypia in 22 133 subjects

BACKGROUND AND AIM

The aim of this study was to identify factors affecting persistent gastric regenerating atypia and determine the effect of Helicobacter pylori eradication on the course of this lesion.

METHODS

In cross-sectional setting, comprehensive health check-up subjects who underwent both endoscopy and H. pylori test from 2001 to 2009 were included. The association between H. pylori and gastric regenerating atypia was evaluated. In cohort setting, patients with regenerating atypia who underwent H. pylori test from 2001 to 2013 were included. Factors affecting positive pathology (persistent regenerating atypia or new development of neoplasm) in patients with regenerating atypia at baseline were investigated.

RESULTS

In cross-sectional setting, regenerating atypia was observed in 1.1% (241/22 133). H. pylori infection was associated with gastric regenerating atypia (adjusted odds ratio, 1.47; 95% confidence interval [CI], 1.12-1.91). In cohort setting, 310 patients with regenerating atypia were finally eligible. Positive pathology rate during follow up was 16.1% (15/93) in the persistent infection group, 2.8% (3/106) in successful eradication group, and 4.5% (5/111) in baseline H. pylori-negative group. Persistent H. pylori infection increased the risk of positive pathology (adjusted risk ratio [RR], 7.18; 95% CI, 1.95-26.48) compared to H. pylori eradication group. Persistent H. pylori infection increased the risk of regenerative atypia (adjusted RR, 5.70; 95% CI, 1.46-22.17) and new neoplasm (adjusted RR, 10.74; 95% CI, 1.10-105.17) compared to baseline negative H. pylori.

CONCLUSIONS

H. pylori infection is an independent risk factor for gastric regenerating atypia. Eradication of H. pylori seems helpful for regression of regenerating atypia.

Risk of Malignancy in Adenomas Detected During Screening Colonoscopy

BACKGROUND & AIMS

A higher incidence of proximal interval cancers after colonoscopy has been reported in several follow-up studies. One possible explanation for this might be that proximally located adenomas have greater malignant potential. The aim of the present study was to assess the risk of malignancy in proximal versus distal adenomas in patients included in a large screening colonoscopy database; adenoma shape and the patients' age and sex distribution were also analyzed.

METHODS

Data for 2007-2012 from the German National Screening Colonoscopy Registry, including 594,614 adenomas identified during 2,532,298 screening colonoscopies, were analyzed retrospectively. The main outcome measure was the rate of high-grade dysplasia (HGD) in adenomas, used as a surrogate marker for the risk of malignancy. Odds ratios (ORs) for the rate of HGD found in adenomas were analyzed in relation to patient- and adenoma-related factors using multivariate analysis.

RESULTS

HGD histology was noted in 20,873 adenomas (3.5%). Proximal adenoma locations were not associated with a higher HGD rate. The most significant risk factor for HGD was adenoma size (OR 10.36 ≥1 cm vs <1 cm), followed by patient age (OR 1.26 and 1.46 for age groups 65-74 and 75-84 vs 55-64 years) and sex (OR 1.15 male vs female). In comparison with flat adenomas as a reference lesion, sessile lesions had a similar HGD rate (OR 1.02) and pedunculated adenomas had a higher rate (OR 1.23). All associations were statistically significant (P ≤ .05).

CONCLUSIONS

In this large screening database, it was found that the rates of adenomas with HGD are similar in the proximal and distal colon. The presence of HGD as a risk marker alone does not explain higher rates of proximal interval colorectal cancer. We suggest that certain lesions (flat, serrated lesions) may be missed in the proximal colon and may acquire a more aggressive biology over time. A combination of endoscopy-related factors and biology may therefore account for higher rates of proximal versus distal interval colorectal cancer.

Safety of duodenal ampullectomy for benign periampullary tumors

Backgrounds/Aims

Surgical resection, such as pancreaticoduodenectomy (PD), is used for treatment of benign periampullary tumors, but high morbidity and mortality resulting from PD can be a huddle. The aim of this study is to suggest a safe and less invasive procedure for treatment of benign periampullary tumors.

Methods

From January 2001 to September 2016, 31 patients with ampulla of Vater (AOV) tumors were reviewed retrospectively. Patients who were confirmed with malignancy through biopsy were excluded, except for one patient with malignancy and multiple underlying diseases. To investigate the safety and availability of transduodenal ampullectomy (TDA), TDA and endoscopic papillectomy (EP) were compared.

Results

There was no significant difference in the occurrence of complications between the TDA group and EP group (p=0.145), and the resection margins were negative in both groups. There was no recurrence in patients who had TDA, while one patient had a recurrence after EP.

Conclusions

This study suggests that TDA is as safe as EP for treating benign periampullary tumors.

Transduodenal Ampullectomy for the Treatment of Early-Stage Ampulla of Vater Cancer

BACKGROUND

Transduodenal ampullectomy (TDA) is a less invasive procedure than pancreaticoduodenectomy (PD). However, the outcomes of TDA and PD have been compared rarely in early ampullary cancer.

METHODS

From September 1994 to June 2013, the patients who underwent curative surgery for Tis or T1 ampulla of Vater neoplasm were identified. The patients were divided into two groups according to the types of surgery; TDA group and PD group. The patient characteristics and survival outcomes were retrospectively investigated between the two groups.

RESULTS

Total 137 patients were included in this study. The 18 patients underwent TDA and 119 patients underwent PD for Tis or T1 ampullary cancer. There was no lymph node metastasis in the patients with Tis tumor although 10 of 104 patients had lymph node metastasis in T1 cancer. After a median follow-up of 50 months (range, 6-148), there were no recurrence after TDA for Tis tumor. However, the TDA was associated with higher local recurrence rate than PD in the patients with T1 ampullary cancer on Kaplan-Meier survival analysis (p = 0.007).

CONCLUSION

The TDA is feasible treatment for Tis ampulla of Vater neoplasm. However, TDA is unsuitable for the treatment of T1 ampulla of Vater cancer.

Fiber-bundle microendoscopy with sub-diffuse reflectance spectroscopy and intensity mapping for multimodal optical biopsy of stratified epithelium

Early detection of structural or functional changes in dysplastic epithelia may be crucial for improving long-term patient care. Recent work has explored myriad non-invasive or minimally invasive "optical biopsy" techniques for diagnosing early dysplasia, such as high-resolution microendoscopy, a method to resolve sub-cellular features of apical epithelia, as well as broadband sub-diffuse reflectance spectroscopy, a method that evaluates bulk health of a small volume of tissue. We present a multimodal fiber-based microendoscopy technique that combines high-resolution microendoscopy, broadband (450-750 nm) sub-diffuse reflectance spectroscopy (sDRS) at two discrete source-detector separations (374 and 730 μm), and sub-diffuse reflectance intensity mapping (sDRIM) using a 635 nm laser. Spatial resolution, magnification, field-of-view, and sampling frequency were determined. Additionally, the ability of the sDRS modality to extract optical properties over a range of depths is reported. Following this, proof-of-concept experiments were performed on tissue-simulating phantoms made with poly(dimethysiloxane) as a substrate material with cultured MDA-MB-468 cells. Then, all modalities were demonstrated on a human melanocytic nevus from a healthy volunteer and on resected colonic tissue from a murine model. Qualitative in vivo image data is correlated with reduced scattering and absorption coefficients.

How Commonly Is the Diagnosis of Gastric Low Grade Dysplasia Upgraded following Endoscopic Resection? A Meta-Analysis

Gastric dysplasia is a well-known precancerous lesion. Though the diagnosis of gastric low grade dysplasia (LGD) is generally made from endoscopic forceps biopsy (EFB), the accuracy is doubtful after numerous EFB-proven gastric LGD were upgraded to gastric high grade dysplasia (HGD) or even carcinoma (CA) by further diagnostic test with the procedure of endoscopic resection (ER). We aimed to evaluate the upgraded diagnosis rate (UDR) and the risk factors by ER in EFB-proven gastric LGD lesions. Two investigators independently searched studies reporting the UDR by ER in EFB-proven gastric LGD lesions from databases and analyzed the overall UDR, HGD-UDR and CA-UDR. The pooled UDR by ER in EFB-proven gastric LGD lesions was 25.0% (95% CI, 20.2%-29.8%), made up of HGD-UDR and CA-UDR by rates of 16.7% (95% CI, 12.8%-20.6%) and 6.9% (95% CI, 4.2%-9.6%) respectively. Lesion size larger than 2 cm, surface with depression and nodularity under endoscopic examinations were the major risk factors associated with UDR. In conclusion, one quarter of EFB-proven gastric LGD lesions will be diagnosed as advanced lesions, including gastric HGD (16.7%) and gastric CA (6.9%) by ER. The diagnosis of those LGD lesions with an endoscopic diameter larger than 2cm, and depressed or nodular surface are more likely to be upgraded after ER.

Radical excision of Barrett's esophagus and complete recovery of normal squamous epithelium

To treat Barrett’s esophagus (BE), radiofrequency ablation or cryotherapy are effective treatments for eradicating BE with dysplasia and intestinal metaplasia, and reduce the rates of Barrett’s esophageal adenocarcinoma (BAC). However, patients with BE and dysplasia or early cancer who achieved complete eradication of intestinal metaplasia, BE recurred in 5% within a year, requiring expensive endoscopic surveillances. We performed endoscopic submucosal dissection as complete radically curable treatment procedure for BE with dysplasia, intestinal metaplasia and BAC.